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Malaria

Infectious MONDO:0005136 protozoal infectious disease vector-borne disease

Malaria is a mosquito-borne protozoal infection caused by Plasmodium species, with major global burden from Plasmodium falciparum and Plasmodium vivax. Clinical disease is driven by blood-stage parasitemia, while severe falciparum syndromes involve microvascular sequestration and organ dysfunction, and vivax disease is complicated by relapse from dormant liver hypnozoites.

0
Mappings
0
Definitions
0
Inheritance
6
Pathophysiology
0
Histopathology
10
Phenotypes
7
Genes
6
Treatments
4
Subtypes
4
Differentials
3
Datasets
3
Trials
◆

Subtypes

4
Plasmodium falciparum malaria Not Yet Curated MONDO:0005920
Malaria caused by Plasmodium falciparum with highest risk of severe disease and cerebral complications.
Show evidence (1 reference)
PMID:37924827 SUPPORT Human Clinical
"Plasmodium falciparum strains partly resistant to artemisinins are entrenched in the Greater Mekong region and have emerged in Africa, while Anopheles mosquito vectors continue to evolve physiological and behavioural resistance to insecticides."
Confirms falciparum malaria as a major clinical subtype with distinct resistance and transmission pressures.
Plasmodium vivax malaria Not Yet Curated MONDO:0005921
Malaria caused by Plasmodium vivax, notable for relapse biology driven by dormant liver hypnozoites.
Show evidence (1 reference)
PMID:37748496 SUPPORT Human Clinical
"Primaquine is used to eliminate Plasmodium vivax hypnozoites, but its optimal dosing regimen remains unclear."
Establishes P. vivax as a subtype with hypnozoite biology requiring radical cure.
Cerebral malaria Not Yet Curated MONDO:0005625
Severe neurologic malaria syndrome characterized by brain microvascular pathology, coma, and seizures.
Show evidence (1 reference)
DOI:10.1186/s12987-024-00541-9 SUPPORT In Vitro
"Blood–brain barrier (BBB) disruption is a central feature of cerebral malaria (CM), a severe complication of Plasmodium falciparum (Pf) infections."
Supports cerebral malaria as a distinct severe subtype with BBB-focused pathogenesis.
Recurrent vivax malaria Not Yet Curated MONDO:0005921
Recurrent disease episodes due to relapse from persistent liver hypnozoites after initial infection.
Show evidence (1 reference)
PMID:37748496 SUPPORT Human Clinical
"At day 180, the risk of recurrence was 51·0% (95% CI 48·2-53·9) in 1470 patients treated without primaquine, 19·3% (16·9-21·9) in 2569 patients treated with a low total dose of primaquine (approximately 3·5 mg/kg), and 8·1% (7·0-9·4) in 2811 patients treated with a high total dose of primaquine..."
Demonstrates substantial recurrence burden in vivax malaria and links recurrence to hypnozoite-targeted therapy.
⚙

Pathophysiology

6
Infected erythrocyte sequestration and cytoadherence
In severe falciparum malaria, parasitized erythrocytes sequester in the microvasculature, promoting endothelial injury, impaired perfusion, and downstream organ dysfunction.
erythrocyte link endothelial cell link
cell adhesion link
blood link
Show evidence (1 reference)
PMID:27939609 SUPPORT Human Clinical
"Infected erythrocyte sequestration in the microvasculature plays a critical role in the development of severe disease"
Directly supports sequestration as a central severe-malaria mechanism.
Blood-brain barrier dysfunction in cerebral malaria
Cerebral malaria involves endothelial barrier breakdown with increased permeability and stress responses, linking vascular pathology to severe neurologic phenotypes.
endothelial cell link
inflammatory response link
brain link
Show evidence (2 references)
DOI:10.1186/s12987-024-00541-9 SUPPORT In Vitro
"Blood–brain barrier (BBB) disruption is a central feature of cerebral malaria (CM), a severe complication of Plasmodium falciparum (Pf) infections."
Establishes BBB disruption as a core pathophysiologic feature of cerebral malaria.
DOI:10.1186/s12987-024-00541-9 SUPPORT In Vitro
"After 6-h of co-culture with Pf-iRBCs, hiPSC-BMECs showed reduced TEER and increased sodium fluorescein permeability compared to co-culture with uninfected RBCs, indicative of a leaky barrier."
Demonstrates mechanistic endothelial barrier failure in an in vitro CM model.
EPCR-associated endothelial pathology
Parasite interactions with endothelial protein C receptor (EPCR) are associated with severe disease and suggest a pathway for enhanced vascular injury and dysregulated coagulation-inflammatory signaling.
endothelial cell link
inflammatory response link
Show evidence (1 reference)
PMID:27939609 SUPPORT Human Clinical
"The recent discovery that parasite binding to endothelial protein C receptor (EPCR) is associated with severe disease has suggested new mechanisms of pathology and provided new avenues for severe malaria adjunctive therapy research."
Supports EPCR-linked endothelial pathology as a severity mechanism.
Cerebrovascular CD8-positive T-cell engagement
Pediatric cerebral malaria includes intravascular and perivascular CD8-positive T-cell engagement at the cerebrovasculature, supporting an immune-mediated component of neurologic injury.
T cell link
inflammatory response link
brain link
Show evidence (2 references)
PMID:31821175 SUPPORT Human Clinical
"We identified effector CD3+CD8+ T cells engaged on the cerebrovasculature in 69% of CM+ HIV- children."
Provides direct human tissue evidence for cerebrovascular CD8-positive T-cell involvement.
PMID:31821175 SUPPORT Human Clinical
"Within the studied cohort, CM is associated with cerebrovascular engagement of CD3+CD8+ T cells, which is exacerbated by HIV coinfection."
Confirms association between cerebral malaria and cerebrovascular CD8-positive T-cell activity.
ABO-dependent rosetting and severe malaria risk
Host ABO genotype modifies falciparum rosetting behavior and contributes to differential risk of severe malaria.
erythrocyte link
cell adhesion link
blood link
Show evidence (2 references)
PMID:37708213 SUPPORT Human Clinical
"Blood group O is associated with protection against severe malaria and reduced size and stability of P. falciparum-host red blood cell (RBC) rosettes compared to non-O blood groups."
Supports RBC rosetting and host blood-group dependence in severe malaria risk.
PMID:37708213 SUPPORT Human Clinical
"In the case-control study, compared to OO, the double dose genotypes consistently had higher odds ratios (OR) for severe malaria than single dose genotypes, with AB (OR 1.93) and AO (OR 1.27) showing most marked difference (p = 0.02, Wald test)."
Restricts this evidence item to human case-control findings on genotype-specific severe-malaria risk.
Hypnozoite persistence and vivax relapse
Dormant P. vivax hypnozoites in the liver sustain recurrent malaria episodes unless eradicated with radical cure.
liver link
Show evidence (1 reference)
PMID:37748496 SUPPORT Human Clinical
"Primaquine is used to eliminate Plasmodium vivax hypnozoites, but its optimal dosing regimen remains unclear."
Directly links dormant hypnozoites to the need for radical cure in recurrent vivax malaria.
⬡

Causal Graph

Referential integrity issues (1):
  • Target 'Recurrent vivax malaria' (from 'Hypnozoite persistence and vivax relapse') not found in named elements
graph LR
    Recurrent_vivax_malaria["Recurrent vivax malaria"]
    Seizure["Seizure"]
    Infected_erythrocyte_sequestration_and_cytoadherence["Infected erythrocyte sequestration and cytoadherence"]
    Coma["Coma"]
    Blood_brain_barrier_dysfunction_in_cerebral_malaria["Blood-brain barrier dysfunction in cerebral malaria"]
    Hypnozoite_persistence_and_vivax_relapse["Hypnozoite persistence and vivax relapse"]

    Infected_erythrocyte_sequestration_and_cytoadherence --> Blood_brain_barrier_dysfunction_in_cerebral_malaria
    Blood_brain_barrier_dysfunction_in_cerebral_malaria --> Coma
    Blood_brain_barrier_dysfunction_in_cerebral_malaria --> Seizure
    Hypnozoite_persistence_and_vivax_relapse -.-> Recurrent_vivax_malaria

    style Recurrent_vivax_malaria fill:#fee2e2,stroke:#dc2626,stroke-dasharray: 5 5
    style Seizure fill:#fef3c7
    style Infected_erythrocyte_sequestration_and_cytoadherence fill:#dbeafe
    style Coma fill:#fef3c7
    style Blood_brain_barrier_dysfunction_in_cerebral_malaria fill:#dbeafe
    style Hypnozoite_persistence_and_vivax_relapse fill:#dbeafe
●

Phenotypes

10
Blood(2) Cardiovascular(1) Digestive(1) Metabolism(1) Nervous System(3) Constitutional(1) Other(1)
Blood 2
Anemia FREQUENT Anemia (HP:0001903)
Show evidence (1 reference)
PMID:8644955 SUPPORT Human Clinical
"There were no deaths, and complications were limited to thrombocytopenia and anemia."
Clinical complications in falciparum malaria include anemia.
Thrombocytopenia FREQUENT Thrombocytopenia (HP:0001873)
Show evidence (1 reference)
PMID:8644955 SUPPORT Human Clinical
"There were no deaths, and complications were limited to thrombocytopenia and anemia."
Directly supports thrombocytopenia as a clinical complication.
Cardiovascular 1
Splenomegaly OCCASIONAL Splenomegaly (HP:0001744)
Show evidence (1 reference)
PMID:25889074 SUPPORT Human Clinical
"Fever, tachycardia, pallor and abdominal pain on palpation were more frequent in P. falciparum patients, whereas mild hepatomegaly and splenomegaly were mostly observed with P. vivax."
Large Colombian clinical surveillance cohort documents splenomegaly, especially in vivax infection.
Digestive 1
Vomiting FREQUENT Vomiting (HP:0002013)
Show evidence (1 reference)
PMID:8644955 SUPPORT Human Clinical
"The most common documented symptoms were fever (100%), chills (65%), vomiting (60%), anorexia (45%), and headache (45%)."
Case-series symptom profile supports vomiting as a frequent manifestation.
Metabolism 1
Fever VERY_FREQUENT Fever (HP:0001945)
Show evidence (1 reference)
PMID:8644955 SUPPORT Human Clinical
"The most common documented symptoms were fever (100%), chills (65%), vomiting (60%), anorexia (45%), and headache (45%)."
Clinical case-series data show fever as the most frequent presenting feature.
Nervous System 3
Headache FREQUENT Headache (HP:0002315)
Show evidence (1 reference)
PMID:8644955 SUPPORT Human Clinical
"The most common documented symptoms were fever (100%), chills (65%), vomiting (60%), anorexia (45%), and headache (45%)."
Reported headache prevalence supports inclusion as a common malaria phenotype.
Coma OCCASIONAL Coma (HP:0001259)
Show evidence (1 reference)
PMID:40701686 SUPPORT Human Clinical
"The disease is defined clinically as an otherwise unexplained coma in someone with malaria parasitemia."
Human clinical neurology review defines coma as the core phenotype of cerebral malaria.
Seizure OCCASIONAL Seizure (HP:0001250)
Show evidence (1 reference)
PMID:40701686 SUPPORT Human Clinical
"Acute seizures are common and increasing numbers of them during the index illness are associated with a greater likelihood of adverse outcomes."
Human clinical evidence supports seizures as common, prognostically relevant cerebral-malaria manifestations.
Constitutional 1
Myalgia FREQUENT Myalgia (HP:0003326)
Show evidence (1 reference)
PMID:17568940 SUPPORT Human Clinical
"Headache (59.8%), fever (57.1%), and myalgia (48.4%) were the most frequent symptoms."
Prospective cohort data identifies myalgia among the most frequent malaria symptoms.
Other 1
Chills FREQUENT Chills (HP:0025143)
Show evidence (1 reference)
PMID:8644955 SUPPORT Human Clinical
"The most common documented symptoms were fever (100%), chills (65%), vomiting (60%), anorexia (45%), and headache (45%)."
Clinical series directly reports chills as a frequent presenting symptom.
🧬

Genetic Associations

7
HBB (HbS trait) (Protective)
Show evidence (2 references)
PMID:22445352 SUPPORT Human Clinical
"Meta-analysis of case-control studies showed a decreased risk of severe P. falciparum malaria in individuals with haemoglobin AS (OR 0·09, 95% CI 0·06-0·12), haemoglobin CC (0·27, 0·11-0·63), haemoglobin AC (0·83, 0·67-0·96), homozygous α-thalassaemia (0·63, 0·48-0·83), and heterozygous..."
Meta-analysis provides strong human clinical evidence for marked severe-malaria protection in HbAS.
PMID:23035141 SUPPORT Human Clinical
"Although sickle cell trait protects against severe disease due to Plasmodium falciparum, it has not been clear whether sickle trait also protects against asymptomatic infection (parasitemia)."
Confirms HbAS as a major protective modifier in falciparum malaria.
G6PD (Protective modifier and pharmacogenomic risk factor)
Show evidence (2 references)
PMID:17355169 SUPPORT Human Clinical
"Our results indicate that the uniform state of G6PD deficiency in hemizygous male children conferred significant protection against severe, life-threatening malaria, and that it may have likewise protected homozygous female children."
Case-control evidence supports genotype-specific protection from severe malaria.
PMID:24372186 SUPPORT Human Clinical
"It is now clear that it is not good practice to give one of these drugs before testing a person for his/her G6PD status, especially in populations in whom G6PD deficiency is common."
Supports clinically important pharmacogenomic implications for primaquine safety.
ACKR1 (Duffy antigen receptor for chemokines) (Strong protective modifier for Plasmodium vivax)
Show evidence (2 references)
PMID:30218021 SUPPORT Human Clinical
"The variants of the Duffy Antigen/Receptor for Chemokines (DARC) gene have probably been selected by malaria parasites, particularly the FY*O allele, which is fixed in sub-Saharan Africa and confers resistance to Plasmodium vivax infection."
Human population genetics evidence supports Duffy-null resistance against vivax malaria.
PMID:37399221 PARTIAL Human Clinical
"This study confirms that Duffy-negativity does not provide complete protection against P. vivax infection."
Adds modern nuance that protection is strong but not absolute in all endemic contexts.
HBB (HbC) (Protective)
Show evidence (1 reference)
PMID:15295709 SUPPORT Human Clinical
"HbAC did not prevent infection but reduced the odds of developing severe malaria and severe anemia."
Case-control data supports protection from severe outcomes despite ongoing infection risk.
HBA1/HBA2 (alpha-thalassemia) (Protective)
Show evidence (1 reference)
PMID:22445352 SUPPORT Human Clinical
"Meta-analysis of case-control studies showed a decreased risk of severe P. falciparum malaria in individuals with haemoglobin AS (OR 0·09, 95% CI 0·06-0·12), haemoglobin CC (0·27, 0·11-0·63), haemoglobin AC (0·83, 0·67-0·96), homozygous α-thalassaemia (0·63, 0·48-0·83), and heterozygous..."
Meta-analysis shows significant protective effects for alpha-thalassemia genotypes.
HBB (beta-thalassemia trait) (Protective (lower parasitemia))
Show evidence (2 references)
PMID:8846492 SUPPORT Human Clinical
"The mean parasitaemia levels of patients with alpha- or beta-thalassaemia trait or with severe glucose-6-phosphate dehydrogenase (G6PD) deficiency were lower than those of individuals with normal haemoglobin AA or with heterozygous haemoglobin E."
Human observational data supports reduced parasitemia in beta-thalassemia trait.
PMID:22445352 PARTIAL Human Clinical
"Few clinical studies have investigated β-thalassaemia, haemoglobin E, P. vivax malaria, or pregnancy-associated malaria."
Indicates supporting literature is more limited than for other major malaria-protective polymorphisms.
ABO (Susceptibility)
Show evidence (1 reference)
PMID:37708213 SUPPORT Human Clinical
"In the case-control study, compared to OO, the double dose genotypes consistently had higher odds ratios (OR) for severe malaria than single dose genotypes, with AB (OR 1.93) and AO (OR 1.27) showing most marked difference (p = 0.02, Wald test)."
Human case-control data support increased severe-malaria risk in double-dose non-O genotypes.
💊

Treatments

6
Artemisinin-based antimalarial therapy MAXO:0000058
Oral or parenteral artemisinin-based therapy remains the treatment mainstay for malaria.
Show evidence (1 reference)
PMID:37924827 SUPPORT Human Clinical
"Parasitological diagnosis and treatment with oral or parenteral artemisinin-based therapy is the mainstay of patient management."
Directly supports frontline antimalarial pharmacotherapy.
Primaquine radical cure for vivax malaria MAXO:0000058
Primaquine reduces recurrent vivax malaria by targeting dormant liver hypnozoites.
Mechanism Target:
INHIBITS Hypnozoite persistence and vivax relapse — Primaquine targets dormant hypnozoites to reduce recurrent episodes.
Show evidence (1 reference)
PMID:37748496 SUPPORT Human Clinical
"Increasing the total dose of primaquine from 3·5 mg/kg to 7 mg/kg can reduce P vivax recurrences by more than 50% in most endemic regions"
Supports mechanism-linked reduction in relapse burden.
Show evidence (1 reference)
PMID:37748496 SUPPORT Human Clinical
"Compared with treatment without primaquine, the rate of P vivax recurrence was lower after treatment with low-dose primaquine (adjusted hazard ratio 0·21, 95% CI 0·17-0·27; p<0·0001) and high-dose primaquine (0·10, 0·08-0·12; p<0·0001)."
Demonstrates major recurrence-risk reduction with primaquine.
Supportive care in severe malaria MAXO:0000950
Severe malaria management includes organ support and restrictive fluid strategy to improve survival.
Show evidence (1 reference)
PMID:37924827 SUPPORT Human Clinical
"Timely blood transfusion, renal replacement therapy, and restrictive fluid therapy can improve survival in severe malaria."
Supports critical-care supportive interventions in severe disease.
Insecticide-treated bed nets MAXO:0000001
Insecticide-treated bed nets are a core vector-control intervention that reduces malaria burden by limiting mosquito exposure.
Show evidence (1 reference)
PMID:22445352 SUPPORT Human Clinical
"including intermittent preventive antimalarial therapy in children (87% to 69%)74,75 or infants (38%)76 and the use of insecticide-treated bed nets (45%).77"
Human epidemiologic synthesis identifies insecticide-treated bed nets as a major malaria-control intervention.
Intermittent preventive treatment and seasonal chemoprevention MAXO:0000058
Drug-based preventive strategies such as IPTp and seasonal chemoprevention reduce malaria morbidity in high-risk populations.
Show evidence (1 reference)
PMID:37924827 SUPPORT Human Clinical
"Rigorous use of intermittent preventive treatment in pregnancy and infancy and seasonal chemoprevention, potentially combined with pre-erythrocytic vaccines endorsed by WHO in 2021 and 2023, can substantially reduce malaria morbidity."
Directly supports IPTp/infancy preventive treatment and seasonal chemoprevention as morbidity-reducing strategies.
Pre-erythrocytic malaria vaccination (RTS,S and R21) MAXO:0001017
WHO-endorsed pre-erythrocytic vaccines are deployed to reduce clinical malaria burden in endemic pediatric populations.
Show evidence (1 reference)
PMID:37924827 SUPPORT Human Clinical
"Rigorous use of intermittent preventive treatment in pregnancy and infancy and seasonal chemoprevention, potentially combined with pre-erythrocytic vaccines endorsed by WHO in 2021 and 2023, can substantially reduce malaria morbidity."
Supports clinical deployment of RTS,S (2021) and R21 (2023) era malaria vaccines as morbidity-reduction interventions.
🔀

Differential Diagnoses

4

Conditions with similar clinical presentations that must be differentiated from Malaria:

Dengue disease MONDO:0005502
Overlapping Features Mosquito-borne viral febrile illness that frequently overlaps clinically with malaria in tropical settings.
Distinguishing Features
  • Prominent retro-orbital pain, rash, and severe myalgia are more typical of dengue.
  • Plasma leakage and hemoconcentration with severe thrombocytopenia support severe dengue.
  • Dengue NS1 antigen or serology supports dengue over malaria when blood film/RDT for malaria is negative.
Show evidence (1 reference)
PMID:27759344 SUPPORT Human Clinical
"Moreover it is a great mimic of co-existing epidemics like Malaria, Chikungunya and Zika virus disease, which are also mosquito-borne diseases."
Review explicitly identifies dengue as a clinical mimic of malaria in co-endemic settings.
chikungunya MONDO:0017941
Overlapping Features Arboviral febrile illness that can be confused with malaria, especially during outbreaks.
Distinguishing Features
  • Severe incapacitating polyarthralgia with prolonged joint symptoms is more characteristic of chikungunya.
  • Maculopapular rash is common and cyclic parasitemia is absent.
  • Chikungunya PCR/serology with negative malaria parasitology supports chikungunya.
Show evidence (1 reference)
PMID:27759344 SUPPORT Human Clinical
"Moreover it is a great mimic of co-existing epidemics like Malaria, Chikungunya and Zika virus disease, which are also mosquito-borne diseases."
Supports chikungunya as an overlapping mosquito-borne differential diagnosis for malaria.
typhoid fever Not Yet Curated MONDO:0005619
Overlapping Features Invasive Salmonella infection causing prolonged fever that can resemble uncomplicated malaria.
Distinguishing Features
  • Sustained stepwise fever pattern with abdominal symptoms and enteric features.
  • Positive blood culture for Salmonella Typhi supports typhoid fever.
  • Lack of malaria parasitemia on repeated testing argues against malaria.
Show evidence (1 reference)
PMID:26261776 SUPPORT Human Clinical
"Since the symptoms and signs are non-specific and resemble other tropical infections like malaria, enteric fever, dengue or leptospirosis, appropriate laboratory tests are necessary to confirm diagnosis."
Directly identifies enteric fever (typhoid) as a key tropical differential when evaluating malaria-like febrile illness.
leptospirosis Not Yet Curated MONDO:0005825
Overlapping Features Zoonotic bacterial febrile illness with multiorgan involvement that can mimic severe malaria.
Distinguishing Features
  • Exposure to contaminated water or animal urine supports leptospirosis risk.
  • Conjunctival suffusion, jaundice, and acute kidney injury are suggestive in severe cases.
  • Positive leptospira serology/PCR with negative malaria parasitology supports leptospirosis.
Show evidence (1 reference)
PMID:26261776 SUPPORT Human Clinical
"Since the symptoms and signs are non-specific and resemble other tropical infections like malaria, enteric fever, dengue or leptospirosis, appropriate laboratory tests are necessary to confirm diagnosis."
Supports leptospirosis as a common mimic requiring targeted testing in malaria-like presentations.
📊

Related Datasets

3
Whole blood transcriptome of childhood malaria geo:GSE1124
Whole-blood microarray profiling across asymptomatic infection, uncomplicated malaria, severe malarial anemia, cerebral malaria, and healthy controls in African children.
human MICROARRAY n=47 Affymetrix Human Genome U133A and...
whole blood
Conditions: asymptomatic Plasmodium falciparum infection uncomplicated malaria severe malarial anemia cerebral malaria healthy controls
PMID:30638864
GEO series metadata reports pooled whole-blood expression profiling across pediatric malaria severity strata.
Blood transcriptional profiles discriminates cerebral and mild malaria patient living in Senegal geo:GSE116306
PBMC microarray profiling comparing mild and cerebral malaria at clinical presentation in Senegalese participants.
human MICROARRAY n=16 Agilent SurePrint G3 Human GE 8x60K...
peripheral blood mononuclear cell
Conditions: mild malaria cerebral malaria
GEO series metadata indicates no linked PubMed citation currently recorded in GEO.
Whole-blood transcriptional signatures composed of erythropoietic and Nrf2-regulated genes differ between cerebral malaria and severe malarial anemia geo:GSE117613
Whole-blood transcriptome microarray study in Ugandan children comparing cerebral malaria, severe malarial anemia, and community controls without P. falciparum infection.
human MICROARRAY n=46 Illumina HumanHT-12 v4 Expression BeadChip
whole blood
Conditions: cerebral malaria severe malarial anemia community control without Plasmodium falciparum infection
PMID:30060095
Captures host whole-blood transcriptional differences between major severe-malaria syndromes.
🔬

Clinical Trials

3
NCT04704830 PHASE_III UNKNOWN
Phase III multicenter trial evaluating efficacy of R21/Matrix-M in African children.
Target Phenotypes: Fever ↗
Show evidence (1 reference)
clinicaltrials:NCT04704830 SUPPORT Human Clinical
"A Phase III randomized controlled multi-centre trial to evaluate the efficacy of the R21/Matrix-M vaccine in African children against clinical malaria"
Trial registry evidence for phase III vaccine efficacy evaluation in malaria.
NCT04158713 PHASE_III UNKNOWN
Placebo-controlled chemoprevention trial of monthly dihydroartemisinin-piperaquine in HIV-infected pregnant participants on cotrimoxazole.
Target Phenotypes: Fever ↗ Anemia ↗
Show evidence (1 reference)
clinicaltrials:NCT04158713 SUPPORT Human Clinical
"This is a 2-arm, individually-randomized, multi-centre, placebo-controlled superiority trial comparing the safety and efficacy of daily CTX plus monthly DP ('CTX-DP') versus daily CTX plus monthly placebo-DP (i.e. 'CTX-alone', control arm) to reduce malaria and the adverse effects of malaria in..."
Registry record supports active clinical testing of preventive pharmacotherapy in a high-risk population.
NCT05019729 PHASE_I UNKNOWN
Phase I controlled human malaria infection study evaluating safety and protective efficacy of anti-malaria monoclonal antibody L9LS.
Target Phenotypes: Fever ↗
Show evidence (1 reference)
clinicaltrials:NCT05019729 SUPPORT Human Clinical
"Most participants took part in the controlled human malaria infection (CHMI) or malaria challenge to find out if L9LS prevents malaria after being bitten by infected mosquitos."
Registry evidence supports early-phase interventional prevention trial design.
{ }

Source YAML

click to show 
name: Malaria
creation_date: "2026-02-20T00:00:00Z"
updated_date: "2026-02-20T16:02:29Z"
description: >-
  Malaria is a mosquito-borne protozoal infection caused by Plasmodium species,
  with major global burden from Plasmodium falciparum and Plasmodium vivax.
  Clinical disease is driven by blood-stage parasitemia, while severe falciparum
  syndromes involve microvascular sequestration and organ dysfunction, and vivax
  disease is complicated by relapse from dormant liver hypnozoites.
category: Infectious
disease_term:
  preferred_term: malaria
  term:
    id: MONDO:0005136
    label: malaria
parents:
- protozoal infectious disease
- vector-borne disease
synonyms:
- Paludism
- Marsh fever
has_subtypes:
- name: Plasmodium falciparum malaria
  subtype_term:
    preferred_term: Plasmodium falciparum malaria
    term:
      id: MONDO:0005920
      label: Plasmodium falciparum malaria
  description: Malaria caused by Plasmodium falciparum with highest risk of severe disease and cerebral complications.
  evidence:
  - reference: PMID:37924827
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Plasmodium falciparum strains partly resistant to artemisinins are entrenched in the Greater Mekong region and have emerged in Africa, while Anopheles mosquito vectors continue to evolve physiological and behavioural resistance to insecticides."
    explanation: Confirms falciparum malaria as a major clinical subtype with distinct resistance and transmission pressures.
- name: Plasmodium vivax malaria
  subtype_term:
    preferred_term: Plasmodium vivax malaria
    term:
      id: MONDO:0005921
      label: Plasmodium vivax malaria
  description: Malaria caused by Plasmodium vivax, notable for relapse biology driven by dormant liver hypnozoites.
  evidence:
  - reference: PMID:37748496
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Primaquine is used to eliminate Plasmodium vivax hypnozoites, but its optimal dosing regimen remains unclear."
    explanation: Establishes P. vivax as a subtype with hypnozoite biology requiring radical cure.
- name: Cerebral malaria
  subtype_term:
    preferred_term: cerebral malaria
    term:
      id: MONDO:0005625
      label: cerebral malaria
  description: Severe neurologic malaria syndrome characterized by brain microvascular pathology, coma, and seizures.
  evidence:
  - reference: DOI:10.1186/s12987-024-00541-9
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "Blood–brain barrier (BBB) disruption is a central feature of cerebral malaria (CM), a severe complication of Plasmodium falciparum (Pf) infections."
    explanation: Supports cerebral malaria as a distinct severe subtype with BBB-focused pathogenesis.
- name: Recurrent vivax malaria
  subtype_term:
    preferred_term: Plasmodium vivax malaria
    term:
      id: MONDO:0005921
      label: Plasmodium vivax malaria
  description: Recurrent disease episodes due to relapse from persistent liver hypnozoites after initial infection.
  evidence:
  - reference: PMID:37748496
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "At day 180, the risk of recurrence was 51·0% (95% CI 48·2-53·9) in 1470 patients treated without primaquine, 19·3% (16·9-21·9) in 2569 patients treated with a low total dose of primaquine (approximately 3·5 mg/kg), and 8·1% (7·0-9·4) in 2811 patients treated with a high total dose of primaquine (approximately 7 mg/kg), regardless of primaquine treatment duration."
    explanation: Demonstrates substantial recurrence burden in vivax malaria and links recurrence to hypnozoite-targeted therapy.
infectious_agent:
- name: Plasmodium falciparum
  infectious_agent_term:
    preferred_term: Plasmodium falciparum
    term:
      id: NCBITaxon:5833
      label: Plasmodium falciparum
  description: The dominant species causing severe malaria syndromes, including cerebral malaria.
  evidence:
  - reference: DOI:10.1186/s12987-024-00541-9
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "Blood–brain barrier (BBB) disruption is a central feature of cerebral malaria (CM), a severe complication of Plasmodium falciparum (Pf) infections."
    explanation: Identifies P. falciparum as a major causative agent linked to severe pathophysiology.
- name: Plasmodium vivax
  infectious_agent_term:
    preferred_term: Plasmodium vivax
    term:
      id: NCBITaxon:5855
      label: Plasmodium vivax
  description: A major malaria species characterized by hypnozoite-mediated relapse requiring radical cure.
  evidence:
  - reference: PMID:37748496
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Primaquine is used to eliminate Plasmodium vivax hypnozoites, but its optimal dosing regimen remains unclear."
    explanation: Confirms P. vivax pathobiology and therapeutic implications.
agent_life_cycle:
  description: >-
    Infection proceeds from mosquito inoculation to liver-stage infection and
    blood-stage replication; P. vivax additionally persists as dormant
    hypnozoites that drive relapse.
  hosts:
  - preferred_term: Homo sapiens
    role: mammalian host for liver and blood stages
    term:
      id: NCBITaxon:9606
      label: Homo sapiens
  - preferred_term: Anopheles gambiae
    role: vector host for parasite transmission
    term:
      id: NCBITaxon:7165
      label: Anopheles gambiae
  vectors:
  - Female Anopheles mosquitoes
  life_cycle_stages:
  - name: Mosquito inoculation and hepatic invasion
    description: Sporozoites are inoculated by infected mosquitoes and establish liver infection.
    evidence:
    - reference: PMID:35921449
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "participants underwent controlled human malaria infection in which they were exposed to mosquitoes carrying Plasmodium falciparum (3D7 strain)."
      explanation: Human challenge model directly confirms mosquito-mediated inoculation as the initiating stage.
  - name: Erythrocytic blood-stage replication
    description: Asexual blood-stage replication drives the major symptomatic and severe manifestations of malaria.
    evidence:
    - reference: PMID:37924827
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "Parasitological diagnosis and treatment with oral or parenteral artemisinin-based therapy is the mainstay of patient management."
      explanation: Clinical mainstay centered on parasitological blood-stage diagnosis and treatment supports blood-stage disease biology.
  - name: Hypnozoite latency and relapse (P. vivax)
    description: Dormant liver-stage hypnozoites reactivate and cause recurrent vivax malaria.
    evidence:
    - reference: PMID:37748496
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "Primaquine is used to eliminate Plasmodium vivax hypnozoites, but its optimal dosing regimen remains unclear."
      explanation: Supports dormant liver-stage biology underlying relapse in vivax malaria.
transmission:
- name: Mosquito-borne transmission
  description: Transmission occurs through the bite of infected female Anopheles mosquitoes.
  evidence:
  - reference: PMID:35921449
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "participants underwent controlled human malaria infection in which they were exposed to mosquitoes carrying Plasmodium falciparum (3D7 strain)."
    explanation: Human challenge data directly supports mosquito-borne transmission.
  - reference: PMID:37924827
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Plasmodium falciparum strains partly resistant to artemisinins are entrenched in the Greater Mekong region and have emerged in Africa, while Anopheles mosquito vectors continue to evolve physiological and behavioural resistance to insecticides."
    explanation: Identifies Anopheles mosquitoes as epidemiologically central vectors.
epidemiology:
- name: Global burden in 2022
  description: Malaria remains a high-burden disease with hundreds of millions of cases and substantial mortality.
  evidence:
  - reference: DOI:10.58614/jahsm481
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Globally, an estimated 249 million malaria cases occurred in 2022, leading to 608,000 malaria deaths in a single year."
    explanation: Provides explicit contemporary burden estimates.
  - reference: PMID:40056919
    supports: SUPPORT
    evidence_source: COMPUTATIONAL
    snippet: "Malaria remains a leading cause of illness and death globally, with countries in sub-Saharan Africa bearing a disproportionate burden."
    explanation: Computational burden mapping supports persistent high global and regional burden.
- name: Stalled incidence progress in sub-Saharan Africa
  description: Gains in incidence reduction have plateaued in many high-burden settings since 2015.
  evidence:
  - reference: PMID:40056919
    supports: SUPPORT
    evidence_source: COMPUTATIONAL
    snippet: "We found an ongoing plateau in rates of malaria infection prevalence and case incidence within sub-Saharan Africa, with consistent year-on-year improvements not evident since 2015."
    explanation: Directly supports recent stagnation in incidence reduction.
progression:
- phase: Hepatic stage
  duration: Approximately days to weeks after inoculation
  notes: Clinically silent liver-stage replication precedes blood-stage disease.
  evidence:
  - reference: PMID:35921449
    supports: PARTIAL
    evidence_source: HUMAN_CLINICAL
    snippet: "participants underwent controlled human malaria infection in which they were exposed to mosquitoes carrying Plasmodium falciparum (3D7 strain)."
    explanation: Human challenge model establishes the early post-inoculation phase that precedes parasitemia.
- phase: Blood stage
  duration: Acute symptomatic period
  notes: Blood-stage parasitemia drives febrile illness and organ complications.
  evidence:
  - reference: PMID:37924827
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Parasitological diagnosis and treatment with oral or parenteral artemisinin-based therapy is the mainstay of patient management."
    explanation: Clinical management centered on blood-stage parasitemia supports this progression phase.
- phase: Relapse phase (vivax malaria)
  duration: Recurrent episodes through follow-up windows up to 180 days
  notes: Recurrence in vivax malaria is driven by persistent hypnozoites.
  evidence:
  - reference: PMID:37748496
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "At day 180, the risk of recurrence was 51·0% (95% CI 48·2-53·9) in 1470 patients treated without primaquine, 19·3% (16·9-21·9) in 2569 patients treated with a low total dose of primaquine (approximately 3·5 mg/kg), and 8·1% (7·0-9·4) in 2811 patients treated with a high total dose of primaquine (approximately 7 mg/kg), regardless of primaquine treatment duration."
    explanation: Quantifies recurrent vivax episodes over time and response to hypnozoite-active therapy.
pathophysiology:
- name: Infected erythrocyte sequestration and cytoadherence
  description: >-
    In severe falciparum malaria, parasitized erythrocytes sequester in the
    microvasculature, promoting endothelial injury, impaired perfusion, and
    downstream organ dysfunction.
  cell_types:
  - preferred_term: erythrocyte
    term:
      id: CL:0000232
      label: erythrocyte
  - preferred_term: endothelial cell
    term:
      id: CL:0000115
      label: endothelial cell
  biological_processes:
  - preferred_term: cell adhesion
    term:
      id: GO:0007155
      label: cell adhesion
  locations:
  - preferred_term: blood
    term:
      id: UBERON:0000178
      label: blood
  downstream:
  - target: Blood-brain barrier dysfunction in cerebral malaria
    description: Microvascular sequestration contributes to BBB injury and neurologic manifestations.
  evidence:
  - reference: PMID:27939609
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Infected erythrocyte sequestration in the microvasculature plays a critical role in the development of severe disease"
    explanation: Directly supports sequestration as a central severe-malaria mechanism.
- name: Blood-brain barrier dysfunction in cerebral malaria
  description: >-
    Cerebral malaria involves endothelial barrier breakdown with increased
    permeability and stress responses, linking vascular pathology to severe
    neurologic phenotypes.
  cell_types:
  - preferred_term: endothelial cell
    term:
      id: CL:0000115
      label: endothelial cell
  biological_processes:
  - preferred_term: inflammatory response
    term:
      id: GO:0006954
      label: inflammatory response
  locations:
  - preferred_term: brain
    term:
      id: UBERON:0000955
      label: brain
  downstream:
  - target: Coma
    description: Barrier dysfunction and microvascular pathology contribute to cerebral edema and coma.
  - target: Seizure
    description: Cerebral vascular and inflammatory injury contributes to seizure risk.
  evidence:
  - reference: DOI:10.1186/s12987-024-00541-9
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "Blood–brain barrier (BBB) disruption is a central feature of cerebral malaria (CM), a severe complication of Plasmodium falciparum (Pf) infections."
    explanation: Establishes BBB disruption as a core pathophysiologic feature of cerebral malaria.
  - reference: DOI:10.1186/s12987-024-00541-9
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "After 6-h of co-culture with Pf-iRBCs, hiPSC-BMECs showed reduced TEER and increased sodium fluorescein permeability compared to co-culture with uninfected RBCs, indicative of a leaky barrier."
    explanation: Demonstrates mechanistic endothelial barrier failure in an in vitro CM model.
- name: EPCR-associated endothelial pathology
  description: >-
    Parasite interactions with endothelial protein C receptor (EPCR) are
    associated with severe disease and suggest a pathway for enhanced vascular
    injury and dysregulated coagulation-inflammatory signaling.
  cell_types:
  - preferred_term: endothelial cell
    term:
      id: CL:0000115
      label: endothelial cell
  biological_processes:
  - preferred_term: inflammatory response
    term:
      id: GO:0006954
      label: inflammatory response
  evidence:
  - reference: PMID:27939609
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The recent discovery that parasite binding to endothelial protein C receptor (EPCR) is associated with severe disease has suggested new mechanisms of pathology and provided new avenues for severe malaria adjunctive therapy research."
    explanation: Supports EPCR-linked endothelial pathology as a severity mechanism.
- name: Cerebrovascular CD8-positive T-cell engagement
  description: >-
    Pediatric cerebral malaria includes intravascular and perivascular CD8-positive
    T-cell engagement at the cerebrovasculature, supporting an immune-mediated
    component of neurologic injury.
  cell_types:
  - preferred_term: T cell
    term:
      id: CL:0000084
      label: T cell
  biological_processes:
  - preferred_term: inflammatory response
    term:
      id: GO:0006954
      label: inflammatory response
  locations:
  - preferred_term: brain
    term:
      id: UBERON:0000955
      label: brain
  evidence:
  - reference: PMID:31821175
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We identified effector CD3+CD8+ T cells engaged on the cerebrovasculature in 69% of CM+ HIV- children."
    explanation: Provides direct human tissue evidence for cerebrovascular CD8-positive T-cell involvement.
  - reference: PMID:31821175
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Within the studied cohort, CM is associated with cerebrovascular engagement of CD3+CD8+ T cells, which is exacerbated by HIV coinfection."
    explanation: Confirms association between cerebral malaria and cerebrovascular CD8-positive T-cell activity.
- name: ABO-dependent rosetting and severe malaria risk
  description: >-
    Host ABO genotype modifies falciparum rosetting behavior and contributes to
    differential risk of severe malaria.
  cell_types:
  - preferred_term: erythrocyte
    term:
      id: CL:0000232
      label: erythrocyte
  biological_processes:
  - preferred_term: cell adhesion
    term:
      id: GO:0007155
      label: cell adhesion
  locations:
  - preferred_term: blood
    term:
      id: UBERON:0000178
      label: blood
  evidence:
  - reference: PMID:37708213
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Blood group O is associated with protection against severe malaria and reduced size and stability of P. falciparum-host red blood cell (RBC) rosettes compared to non-O blood groups."
    explanation: Supports RBC rosetting and host blood-group dependence in severe malaria risk.
  - reference: PMID:37708213
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "In the case-control study, compared to OO, the double dose genotypes consistently had higher odds ratios (OR) for severe malaria than single dose genotypes, with AB (OR 1.93) and AO (OR 1.27) showing most marked difference (p = 0.02, Wald test)."
    explanation: Restricts this evidence item to human case-control findings on genotype-specific severe-malaria risk.
- name: Hypnozoite persistence and vivax relapse
  description: >-
    Dormant P. vivax hypnozoites in the liver sustain recurrent malaria episodes
    unless eradicated with radical cure.
  locations:
  - preferred_term: liver
    term:
      id: UBERON:0002107
      label: liver
  downstream:
  - target: Recurrent vivax malaria
    description: Persistence of hypnozoites drives repeated blood-stage episodes.
  evidence:
  - reference: PMID:37748496
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Primaquine is used to eliminate Plasmodium vivax hypnozoites, but its optimal dosing regimen remains unclear."
    explanation: Directly links dormant hypnozoites to the need for radical cure in recurrent vivax malaria.
phenotypes:
- name: Fever
  description: >-
    Fever is the dominant presenting symptom of acute clinical malaria.
  phenotype_term:
    preferred_term: Fever
    term:
      id: HP:0001945
      label: Fever
  frequency: VERY_FREQUENT
  diagnostic: true
  evidence:
  - reference: PMID:8644955
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The most common documented symptoms were fever (100%), chills (65%), vomiting (60%), anorexia (45%), and headache (45%)."
    explanation: Clinical case-series data show fever as the most frequent presenting feature.
- name: Chills
  description: Chills and rigors are common constitutional manifestations in acute malaria.
  phenotype_term:
    preferred_term: Chills
    term:
      id: HP:0025143
      label: Chills
  frequency: FREQUENT
  evidence:
  - reference: PMID:8644955
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The most common documented symptoms were fever (100%), chills (65%), vomiting (60%), anorexia (45%), and headache (45%)."
    explanation: Clinical series directly reports chills as a frequent presenting symptom.
- name: Headache
  description: Headache is a frequent constitutional symptom in symptomatic malaria.
  phenotype_term:
    preferred_term: Headache
    term:
      id: HP:0002315
      label: Headache
  frequency: FREQUENT
  evidence:
  - reference: PMID:8644955
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The most common documented symptoms were fever (100%), chills (65%), vomiting (60%), anorexia (45%), and headache (45%)."
    explanation: Reported headache prevalence supports inclusion as a common malaria phenotype.
- name: Vomiting
  description: Gastrointestinal symptoms including vomiting are common in acute malaria presentations.
  phenotype_term:
    preferred_term: Vomiting
    term:
      id: HP:0002013
      label: Vomiting
  frequency: FREQUENT
  evidence:
  - reference: PMID:8644955
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The most common documented symptoms were fever (100%), chills (65%), vomiting (60%), anorexia (45%), and headache (45%)."
    explanation: Case-series symptom profile supports vomiting as a frequent manifestation.
- name: Myalgia
  description: Muscle pain is a frequent systemic symptom in uncomplicated malaria.
  phenotype_term:
    preferred_term: Myalgia
    term:
      id: HP:0003326
      label: Myalgia
  frequency: FREQUENT
  evidence:
  - reference: PMID:17568940
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Headache (59.8%), fever (57.1%), and myalgia (48.4%) were the most frequent symptoms."
    explanation: Prospective cohort data identifies myalgia among the most frequent malaria symptoms.
- name: Anemia
  description: Malaria can cause clinically significant anemia, especially in severe disease.
  phenotype_term:
    preferred_term: Anemia
    term:
      id: HP:0001903
      label: Anemia
  frequency: FREQUENT
  evidence:
  - reference: PMID:8644955
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "There were no deaths, and complications were limited to thrombocytopenia and anemia."
    explanation: Clinical complications in falciparum malaria include anemia.
- name: Thrombocytopenia
  description: Platelet depletion is a common hematologic complication of malaria.
  phenotype_term:
    preferred_term: Thrombocytopenia
    term:
      id: HP:0001873
      label: Thrombocytopenia
  frequency: FREQUENT
  evidence:
  - reference: PMID:8644955
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "There were no deaths, and complications were limited to thrombocytopenia and anemia."
    explanation: Directly supports thrombocytopenia as a clinical complication.
- name: Splenomegaly
  description: Splenic enlargement is a recognized manifestation in malaria, particularly with vivax-predominant presentations.
  subtype: Plasmodium vivax malaria
  phenotype_term:
    preferred_term: Splenomegaly
    term:
      id: HP:0001744
      label: Splenomegaly
  frequency: OCCASIONAL
  evidence:
  - reference: PMID:25889074
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Fever, tachycardia, pallor and abdominal pain on palpation were more frequent in P. falciparum patients, whereas mild hepatomegaly and splenomegaly were mostly observed with P. vivax."
    explanation: Large Colombian clinical surveillance cohort documents splenomegaly, especially in vivax infection.
- name: Coma
  description: Cerebral malaria can present with coma as a defining severe neurologic manifestation.
  subtype: Cerebral malaria
  severity: Severe
  phenotype_term:
    preferred_term: Coma
    term:
      id: HP:0001259
      label: Coma
  frequency: OCCASIONAL
  diagnostic: true
  evidence:
  - reference: PMID:40701686
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The disease is defined clinically as an otherwise unexplained coma in someone with malaria parasitemia."
    explanation: Human clinical neurology review defines coma as the core phenotype of cerebral malaria.
- name: Seizure
  description: Seizures are a major severe neurologic manifestation in cerebral malaria.
  subtype: Cerebral malaria
  severity: Severe
  phenotype_term:
    preferred_term: Seizure
    term:
      id: HP:0001250
      label: Seizure
  frequency: OCCASIONAL
  diagnostic: true
  evidence:
  - reference: PMID:40701686
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Acute seizures are common and increasing numbers of them during the index illness are associated with a greater likelihood of adverse outcomes."
    explanation: Human clinical evidence supports seizures as common, prognostically relevant cerebral-malaria manifestations.
genetic:
- name: HBB (HbS trait)
  association: Protective
  notes: Sickle cell trait (HbAS) is one of the strongest known host genetic protective modifiers against severe falciparum malaria.
  evidence:
  - reference: PMID:22445352
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Meta-analysis of case-control studies showed a decreased risk of severe P. falciparum malaria in individuals with haemoglobin AS (OR 0·09, 95% CI 0·06-0·12), haemoglobin CC (0·27, 0·11-0·63), haemoglobin AC (0·83, 0·67-0·96), homozygous α-thalassaemia (0·63, 0·48-0·83), and heterozygous α-thalassaemia (0·83, 0·74-0·92)."
    explanation: Meta-analysis provides strong human clinical evidence for marked severe-malaria protection in HbAS.
  - reference: PMID:23035141
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Although sickle cell trait protects against severe disease due to Plasmodium falciparum, it has not been clear whether sickle trait also protects against asymptomatic infection (parasitemia)."
    explanation: Confirms HbAS as a major protective modifier in falciparum malaria.
- name: G6PD
  association: Protective modifier and pharmacogenomic risk factor
  notes: G6PD deficiency can reduce severe-malaria risk in specific genotypes while increasing risk of drug-induced hemolysis with primaquine.
  evidence:
  - reference: PMID:17355169
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Our results indicate that the uniform state of G6PD deficiency in hemizygous male children conferred significant protection against severe, life-threatening malaria, and that it may have likewise protected homozygous female children."
    explanation: Case-control evidence supports genotype-specific protection from severe malaria.
  - reference: PMID:24372186
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "It is now clear that it is not good practice to give one of these drugs before testing a person for his/her G6PD status, especially in populations in whom G6PD deficiency is common."
    explanation: Supports clinically important pharmacogenomic implications for primaquine safety.
- name: ACKR1 (Duffy antigen receptor for chemokines)
  association: Strong protective modifier for Plasmodium vivax
  notes: The FY*O (Duffy-null) background is a major vivax resistance factor, but Duffy-independent vivax infection can still occur.
  evidence:
  - reference: PMID:30218021
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The variants of the Duffy Antigen/Receptor for Chemokines (DARC) gene have probably been selected by malaria parasites, particularly the FY*O allele, which is fixed in sub-Saharan Africa and confers resistance to Plasmodium vivax infection."
    explanation: Human population genetics evidence supports Duffy-null resistance against vivax malaria.
  - reference: PMID:37399221
    supports: PARTIAL
    evidence_source: HUMAN_CLINICAL
    snippet: "This study confirms that Duffy-negativity does not provide complete protection against P. vivax infection."
    explanation: Adds modern nuance that protection is strong but not absolute in all endemic contexts.
- name: HBB (HbC)
  association: Protective
  notes: HbC is associated with reduced severe falciparum malaria risk, with stronger protection in homozygotes.
  evidence:
  - reference: PMID:15295709
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "HbAC did not prevent infection but reduced the odds of developing severe malaria and severe anemia."
    explanation: Case-control data supports protection from severe outcomes despite ongoing infection risk.
- name: HBA1/HBA2 (alpha-thalassemia)
  association: Protective
  notes: Both heterozygous and homozygous alpha-thalassemia reduce severe-malaria risk.
  evidence:
  - reference: PMID:22445352
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Meta-analysis of case-control studies showed a decreased risk of severe P. falciparum malaria in individuals with haemoglobin AS (OR 0·09, 95% CI 0·06-0·12), haemoglobin CC (0·27, 0·11-0·63), haemoglobin AC (0·83, 0·67-0·96), homozygous α-thalassaemia (0·63, 0·48-0·83), and heterozygous α-thalassaemia (0·83, 0·74-0·92)."
    explanation: Meta-analysis shows significant protective effects for alpha-thalassemia genotypes.
- name: HBB (beta-thalassemia trait)
  association: Protective (lower parasitemia)
  notes: Beta-thalassemia trait is associated with lower parasitemia, though evidence is less extensive than for HbAS, HbC, and alpha-thalassemia.
  evidence:
  - reference: PMID:8846492
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The mean parasitaemia levels of patients with alpha- or beta-thalassaemia trait or with severe glucose-6-phosphate dehydrogenase (G6PD) deficiency were lower than those of individuals with normal haemoglobin AA or with heterozygous haemoglobin E."
    explanation: Human observational data supports reduced parasitemia in beta-thalassemia trait.
  - reference: PMID:22445352
    supports: PARTIAL
    evidence_source: HUMAN_CLINICAL
    snippet: "Few clinical studies have investigated β-thalassaemia, haemoglobin E, P. vivax malaria, or pregnancy-associated malaria."
    explanation: Indicates supporting literature is more limited than for other major malaria-protective polymorphisms.
- name: ABO
  association: Susceptibility
  notes: Non-O genotypes are associated with increased falciparum rosetting and elevated severe-malaria risk.
  evidence:
  - reference: PMID:37708213
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "In the case-control study, compared to OO, the double dose genotypes consistently had higher odds ratios (OR) for severe malaria than single dose genotypes, with AB (OR 1.93) and AO (OR 1.27) showing most marked difference (p = 0.02, Wald test)."
    explanation: Human case-control data support increased severe-malaria risk in double-dose non-O genotypes.
diagnosis:
- name: Parasitological diagnosis
  description: Diagnosis is based on direct parasitological confirmation of malaria infection.
  evidence:
  - reference: PMID:37924827
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Parasitological diagnosis and treatment with oral or parenteral artemisinin-based therapy is the mainstay of patient management."
    explanation: Supports parasitological confirmation as core diagnostic practice.
- name: Rapid diagnostic test-based case ascertainment
  description: Rapid diagnostic tests are used in field and clinical settings to define clinical malaria with fever.
  evidence:
  - reference: PMID:40991921
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The primary outcome was clinical malaria in the children, as defined by fever and a positive malaria rapid diagnostic test."
    explanation: Supports RDT-based clinical case definition.
differential_diagnoses:
- name: Dengue disease
  description: Mosquito-borne viral febrile illness that frequently overlaps clinically with malaria in tropical settings.
  distinguishing_features:
  - Prominent retro-orbital pain, rash, and severe myalgia are more typical of dengue.
  - Plasma leakage and hemoconcentration with severe thrombocytopenia support severe dengue.
  - Dengue NS1 antigen or serology supports dengue over malaria when blood film/RDT for malaria is negative.
  disease_term:
    preferred_term: dengue disease
    term:
      id: MONDO:0005502
      label: dengue disease
  evidence:
  - reference: PMID:27759344
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Moreover it is a great mimic of co-existing epidemics like Malaria, Chikungunya and Zika virus disease, which are also mosquito-borne diseases."
    explanation: Review explicitly identifies dengue as a clinical mimic of malaria in co-endemic settings.
- name: chikungunya
  description: Arboviral febrile illness that can be confused with malaria, especially during outbreaks.
  distinguishing_features:
  - Severe incapacitating polyarthralgia with prolonged joint symptoms is more characteristic of chikungunya.
  - Maculopapular rash is common and cyclic parasitemia is absent.
  - Chikungunya PCR/serology with negative malaria parasitology supports chikungunya.
  disease_term:
    preferred_term: chikungunya
    term:
      id: MONDO:0017941
      label: chikungunya
  evidence:
  - reference: PMID:27759344
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Moreover it is a great mimic of co-existing epidemics like Malaria, Chikungunya and Zika virus disease, which are also mosquito-borne diseases."
    explanation: Supports chikungunya as an overlapping mosquito-borne differential diagnosis for malaria.
- name: typhoid fever
  description: Invasive Salmonella infection causing prolonged fever that can resemble uncomplicated malaria.
  distinguishing_features:
  - Sustained stepwise fever pattern with abdominal symptoms and enteric features.
  - Positive blood culture for Salmonella Typhi supports typhoid fever.
  - Lack of malaria parasitemia on repeated testing argues against malaria.
  disease_term:
    preferred_term: typhoid fever
    term:
      id: MONDO:0005619
      label: typhoid fever
  evidence:
  - reference: PMID:26261776
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Since the symptoms and signs are non-specific and resemble other tropical infections like malaria, enteric fever, dengue or leptospirosis, appropriate laboratory tests are necessary to confirm diagnosis."
    explanation: Directly identifies enteric fever (typhoid) as a key tropical differential when evaluating malaria-like febrile illness.
- name: leptospirosis
  description: Zoonotic bacterial febrile illness with multiorgan involvement that can mimic severe malaria.
  distinguishing_features:
  - Exposure to contaminated water or animal urine supports leptospirosis risk.
  - Conjunctival suffusion, jaundice, and acute kidney injury are suggestive in severe cases.
  - Positive leptospira serology/PCR with negative malaria parasitology supports leptospirosis.
  disease_term:
    preferred_term: leptospirosis
    term:
      id: MONDO:0005825
      label: leptospirosis
  evidence:
  - reference: PMID:26261776
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Since the symptoms and signs are non-specific and resemble other tropical infections like malaria, enteric fever, dengue or leptospirosis, appropriate laboratory tests are necessary to confirm diagnosis."
    explanation: Supports leptospirosis as a common mimic requiring targeted testing in malaria-like presentations.
datasets:
- accession: geo:GSE1124
  title: Whole blood transcriptome of childhood malaria
  description: >-
    Whole-blood microarray profiling across asymptomatic infection,
    uncomplicated malaria, severe malarial anemia, cerebral malaria, and
    healthy controls in African children.
  organism:
    preferred_term: human
    term:
      id: NCBITaxon:9606
      label: Homo sapiens
  data_type: MICROARRAY
  sample_types:
  - preferred_term: whole blood
    tissue_term:
      preferred_term: blood
      term:
        id: UBERON:0000178
        label: blood
  sample_count: 47
  conditions:
  - asymptomatic Plasmodium falciparum infection
  - uncomplicated malaria
  - severe malarial anemia
  - cerebral malaria
  - healthy controls
  platform: Affymetrix Human Genome U133A and U133B Arrays
  publication: PMID:30638864
  notes: GEO series metadata reports pooled whole-blood expression profiling across pediatric malaria severity strata.
- accession: geo:GSE116306
  title: Blood transcriptional profiles discriminates cerebral and mild malaria patient living in Senegal
  description: >-
    PBMC microarray profiling comparing mild and cerebral malaria at clinical
    presentation in Senegalese participants.
  organism:
    preferred_term: human
    term:
      id: NCBITaxon:9606
      label: Homo sapiens
  data_type: MICROARRAY
  sample_types:
  - preferred_term: peripheral blood mononuclear cell
    tissue_term:
      preferred_term: blood
      term:
        id: UBERON:0000178
        label: blood
  sample_count: 16
  conditions:
  - mild malaria
  - cerebral malaria
  platform: Agilent SurePrint G3 Human GE 8x60K Microarray
  notes: GEO series metadata indicates no linked PubMed citation currently recorded in GEO.
- accession: geo:GSE117613
  title: Whole-blood transcriptional signatures composed of erythropoietic and Nrf2-regulated genes differ between cerebral malaria and severe malarial anemia
  description: >-
    Whole-blood transcriptome microarray study in Ugandan children comparing
    cerebral malaria, severe malarial anemia, and community controls without
    P. falciparum infection.
  organism:
    preferred_term: human
    term:
      id: NCBITaxon:9606
      label: Homo sapiens
  data_type: MICROARRAY
  sample_types:
  - preferred_term: whole blood
    tissue_term:
      preferred_term: blood
      term:
        id: UBERON:0000178
        label: blood
  sample_count: 46
  conditions:
  - cerebral malaria
  - severe malarial anemia
  - community control without Plasmodium falciparum infection
  platform: Illumina HumanHT-12 v4 Expression BeadChip
  publication: PMID:30060095
  notes: Captures host whole-blood transcriptional differences between major severe-malaria syndromes.
treatments:
- name: Artemisinin-based antimalarial therapy
  description: Oral or parenteral artemisinin-based therapy remains the treatment mainstay for malaria.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
  evidence:
  - reference: PMID:37924827
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Parasitological diagnosis and treatment with oral or parenteral artemisinin-based therapy is the mainstay of patient management."
    explanation: Directly supports frontline antimalarial pharmacotherapy.
- name: Primaquine radical cure for vivax malaria
  description: Primaquine reduces recurrent vivax malaria by targeting dormant liver hypnozoites.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
  target_mechanisms:
  - target: Hypnozoite persistence and vivax relapse
    treatment_effect: INHIBITS
    description: Primaquine targets dormant hypnozoites to reduce recurrent episodes.
    evidence:
    - reference: PMID:37748496
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "Increasing the total dose of primaquine from 3·5 mg/kg to 7 mg/kg can reduce P vivax recurrences by more than 50% in most endemic regions"
      explanation: Supports mechanism-linked reduction in relapse burden.
  evidence:
  - reference: PMID:37748496
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Compared with treatment without primaquine, the rate of P vivax recurrence was lower after treatment with low-dose primaquine (adjusted hazard ratio 0·21, 95% CI 0·17-0·27; p<0·0001) and high-dose primaquine (0·10, 0·08-0·12; p<0·0001)."
    explanation: Demonstrates major recurrence-risk reduction with primaquine.
- name: Supportive care in severe malaria
  description: Severe malaria management includes organ support and restrictive fluid strategy to improve survival.
  treatment_term:
    preferred_term: supportive care
    term:
      id: MAXO:0000950
      label: supportive care
  evidence:
  - reference: PMID:37924827
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Timely blood transfusion, renal replacement therapy, and restrictive fluid therapy can improve survival in severe malaria."
    explanation: Supports critical-care supportive interventions in severe disease.
- name: Insecticide-treated bed nets
  description: Insecticide-treated bed nets are a core vector-control intervention that reduces malaria burden by limiting mosquito exposure.
  treatment_term:
    preferred_term: medical action
    term:
      id: MAXO:0000001
      label: medical action
  evidence:
  - reference: PMID:22445352
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "including intermittent preventive antimalarial therapy in children (87% to 69%)74,75 or infants (38%)76 and the use of insecticide-treated bed nets (45%).77"
    explanation: Human epidemiologic synthesis identifies insecticide-treated bed nets as a major malaria-control intervention.
- name: Intermittent preventive treatment and seasonal chemoprevention
  description: Drug-based preventive strategies such as IPTp and seasonal chemoprevention reduce malaria morbidity in high-risk populations.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
  evidence:
  - reference: PMID:37924827
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Rigorous use of intermittent preventive treatment in pregnancy and infancy and seasonal chemoprevention, potentially combined with pre-erythrocytic vaccines endorsed by WHO in 2021 and 2023, can substantially reduce malaria morbidity."
    explanation: Directly supports IPTp/infancy preventive treatment and seasonal chemoprevention as morbidity-reducing strategies.
- name: Pre-erythrocytic malaria vaccination (RTS,S and R21)
  description: WHO-endorsed pre-erythrocytic vaccines are deployed to reduce clinical malaria burden in endemic pediatric populations.
  treatment_term:
    preferred_term: vaccination
    term:
      id: MAXO:0001017
      label: vaccination
  evidence:
  - reference: PMID:37924827
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Rigorous use of intermittent preventive treatment in pregnancy and infancy and seasonal chemoprevention, potentially combined with pre-erythrocytic vaccines endorsed by WHO in 2021 and 2023, can substantially reduce malaria morbidity."
    explanation: Supports clinical deployment of RTS,S (2021) and R21 (2023) era malaria vaccines as morbidity-reduction interventions.
clinical_trials:
- name: NCT04704830
  phase: PHASE_III
  status: UNKNOWN
  description: Phase III multicenter trial evaluating efficacy of R21/Matrix-M in African children.
  target_phenotypes:
  - preferred_term: Fever
    term:
      id: HP:0001945
      label: Fever
  evidence:
  - reference: clinicaltrials:NCT04704830
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "A Phase III randomized controlled multi-centre trial to evaluate the efficacy of the R21/Matrix-M vaccine in African children against clinical malaria"
    explanation: Trial registry evidence for phase III vaccine efficacy evaluation in malaria.
- name: NCT04158713
  phase: PHASE_III
  status: UNKNOWN
  description: Placebo-controlled chemoprevention trial of monthly dihydroartemisinin-piperaquine in HIV-infected pregnant participants on cotrimoxazole.
  target_phenotypes:
  - preferred_term: Fever
    term:
      id: HP:0001945
      label: Fever
  - preferred_term: Anemia
    term:
      id: HP:0001903
      label: Anemia
  evidence:
  - reference: clinicaltrials:NCT04158713
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "This is a 2-arm, individually-randomized, multi-centre, placebo-controlled superiority trial comparing the safety and efficacy of daily CTX plus monthly DP ('CTX-DP') versus daily CTX plus monthly placebo-DP (i.e. 'CTX-alone', control arm) to reduce malaria and the adverse effects of malaria in 898 (449 per arm) HIV-infected pregnant women on DTG-based cARTs."
    explanation: Registry record supports active clinical testing of preventive pharmacotherapy in a high-risk population.
- name: NCT05019729
  phase: PHASE_I
  status: UNKNOWN
  description: Phase I controlled human malaria infection study evaluating safety and protective efficacy of anti-malaria monoclonal antibody L9LS.
  target_phenotypes:
  - preferred_term: Fever
    term:
      id: HP:0001945
      label: Fever
  evidence:
  - reference: clinicaltrials:NCT05019729
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Most participants took part in the controlled human malaria infection (CHMI) or malaria challenge to find out if L9LS prevents malaria after being bitten by infected mosquitos."
    explanation: Registry evidence supports early-phase interventional prevention trial design.