Astrakhan spotted fever is an acute tick-borne spotted-fever-group rickettsiosis caused by Rickettsia conorii subsp. caspia. Rhipicephalus pumilio or Rhipicephalus sanguineus ticks inoculate the obligately intracellular bacterium into skin, and the resulting illness combines fever, conjunctivitis, regional lymphadenitis, hepatomegaly, hypotension, and a papular-hemorrhagic exanthem.
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name: Astrakhan spotted fever
creation_date: "2026-09-28T10:35:48Z"
category: Infectious Disease
description: >-
Astrakhan spotted fever is an acute tick-borne spotted-fever-group
rickettsiosis caused by Rickettsia conorii subsp. caspia. Rhipicephalus
pumilio or Rhipicephalus sanguineus ticks inoculate the obligately
intracellular bacterium into skin, and the resulting illness combines fever,
conjunctivitis, regional lymphadenitis, hepatomegaly, hypotension, and a
papular-hemorrhagic exanthem.
disease_term:
preferred_term: Astrakhan spotted fever
term:
id: MONDO:0024473
label: Astrakhan spotted fever
parents:
- Spotted fever rickettsiosis
synonyms:
- Astrakhan fever
- Astrakhan fever rickettsiosis
- Astrakhan fever rickettsia infection
references:
- reference: PMID:15766388
title: >-
Proposal to create subspecies of Rickettsia conorii based on multi-locus
sequence typing and an emended description of Rickettsia conorii.
- reference: PMID:12860620
title: Detection of Astrakhan fever rickettsia from ticks in Kosovo.
- reference: PMID:7985764
title: >-
Astrakhan fever rickettsiae: antigenic and genotypic analysis of isolates
obtained from human and Rhipicephalus pumilio ticks.
- reference: PMID:9324803
title: >-
[The primary effect and characteristics of the course of a new tick-borne
rickettsiosis--Astrakhan fever].
- reference: PMID:24059918
title: Recent molecular insights into rickettsial pathogenesis and immunity.
- reference: PMID:12459842
title: >-
Cytokins in the pathogenesis of astrakhan spotted Fever and North Asian
scrub typhus: problems of immunocorrection.
- reference: PMID:12498120
title: "[Status of cellular immunity in patients with Astrakhan fever]."
- reference: PMID:35467375
title: >-
Diagnostic Value of IgA Antibody Measurement in Tick-Borne Spotted Fever
(Astrakhan Rickettsial Fever).
- reference: PMID:8549703
title: Serologic response to rickettsial antigens in patients with Astrakhan fever.
- reference: PMID:15109588
title: Tick-borne rickettsioses in international travellers.
classifications:
harrisons_chapter:
- classification_value: INFECTIOUS_DISEASES
evidence:
- reference: PMID:15766388
reference_title: >-
Proposal to create subspecies of Rickettsia conorii based on
multi-locus sequence typing and an emended description of Rickettsia
conorii.
supports: SUPPORT
evidence_source: OTHER
snippet: >-
Rickettsiae closely related to the Malish strain, the reference
Rickettsia conorii strain, include Indian tick typhus rickettsia (ITTR),
Israeli spotted fever rickettsia (ISFR), and Astrakhan fever
rickettsia (AFR).
explanation: >-
The taxonomic study identifies Astrakhan fever rickettsia as a member
of the bacterial R. conorii complex.
infectious_agent:
- name: Rickettsia conorii subsp. caspia
infectious_agent_term:
preferred_term: Rickettsia conorii subsp. caspia
term:
id: NCBITaxon:302011
label: Rickettsia conorii subsp. caspia
description: >-
R. conorii subsp. caspia is the Astrakhan fever rickettsia lineage of the
R. conorii complex.
evidence:
- reference: PMID:15766388
reference_title: >-
Proposal to create subspecies of Rickettsia conorii based on multi-locus
sequence typing and an emended description of Rickettsia conorii.
supports: SUPPORT
evidence_source: OTHER
snippet: >-
R. conorii subspecies caspia subsp. nov. (type strain = A-167)
explanation: >-
The multilocus taxonomic proposal created Rickettsia conorii subspecies
caspia from the Astrakhan fever rickettsia lineage.
transmission:
- name: Rhipicephalus tick bite transmission
description: >-
Humans acquire Astrakhan spotted fever when infected Rhipicephalus ticks,
including R. pumilio in the Astrakhan focus and R. sanguineus in Kosovo,
inoculate R. conorii subsp. caspia during blood feeding.
evidence:
- reference: PMID:12860620
reference_title: Detection of Astrakhan fever rickettsia from ticks in Kosovo.
supports: SUPPORT
evidence_source: OTHER
snippet: >-
Its agent is a spotted fever group rickettsia, member of the Rickettsia
conorii complex, transmitted to humans by Rhipicephalus sanguineus and
Rhipicephalus pumilio ticks.
explanation: >-
The Kosovo molecular survey names the two Rhipicephalus vectors known
for Astrakhan fever rickettsia.
- reference: PMID:7985764
reference_title: "Astrakhan fever rickettsiae: antigenic and genotypic analysis of isolates obtained from human and Rhipicephalus pumilio ticks."
supports: SUPPORT
evidence_source: IN_VITRO
snippet: >-
Two spotted fever group rickettsia strains, A-108 and A-167, were
isolated from the hemolymph of Rhipicephalus pumilio ticks collected in
the Astrakhan region of Russia, which is area endemic for Astrakhan fever.
explanation: >-
The 1994 Astrakhan study recovered the fever agent from R. pumilio ticks
collected in the endemic Russian focus.
pathophysiology:
- name: Rhipicephalus-Mediated Rickettsia conorii subsp. caspia Inoculation
role: trigger
biological_scale: ORGANISM
description: >-
An infected R. pumilio or R. sanguineus tick bites human skin and delivers
R. conorii subsp. caspia into the dermis, seeding the local and systemic
spotted-fever-group infection.
biological_processes:
- preferred_term: symbiont entry into host
term:
id: GO:0044409
label: symbiont entry into host
downstream:
- target: Obligate Intracytosolic Rickettsial Niche
causal_link_type: DIRECT
description: >-
Tick inoculation delivers the obligately intracellular rickettsia to
host cells.
evidence:
- reference: PMID:12860620
reference_title: Detection of Astrakhan fever rickettsia from ticks in Kosovo.
supports: SUPPORT
evidence_source: OTHER
snippet: >-
Its agent is a spotted fever group rickettsia, member of the Rickettsia
conorii complex, transmitted to humans by Rhipicephalus sanguineus and
Rhipicephalus pumilio ticks.
explanation: >-
The molecular survey states that the Astrakhan fever agent is transmitted
to humans by Rhipicephalus ticks, supporting tick-mediated inoculation as
the initiating exposure.
- name: Obligate Intracytosolic Rickettsial Niche
role: intrinsic_resistance
conforms_to: >-
intracellular_pathogen_persistence#Intracellular Niche and Beta-Lactam
Exclusion
biological_scale: CELLULAR
description: >-
Rickettsia species replicate inside host cells, especially mammalian
microvascular endothelial cells; this shared cytosolic niche is inferred
for R. conorii subsp. caspia from its membership in the spotted-fever
Rickettsia lineage.
cell_types:
- preferred_term: vascular endothelial cell
term:
id: CL:0002139
label: endothelial cell of vascular tree
biological_processes:
- preferred_term: biological process involved in interaction with host
term:
id: GO:0051701
label: biological process involved in interaction with host
downstream:
- target: Rhipicephalus Bite-Site Primary Reaction
causal_link_type: DIRECT
description: >-
The initial dermal rickettsial niche gives rise to the bite-site reaction.
evidence:
- reference: PMID:24059918
reference_title: Recent molecular insights into rickettsial pathogenesis and immunity.
supports: SUPPORT
evidence_source: OTHER
snippet: >-
The unique lifestyle features of rickettsiae include obligate
intracellular parasitism, intracytoplasmic niche within the host cell,
predilection for infection of microvascular endothelium in mammalian
hosts, association with arthropods and the tendency for genomic
reduction.
explanation: >-
The rickettsial review establishes the shared cytosolic and endothelial
tropism inferred for the Astrakhan fever agent.
- name: Rhipicephalus Bite-Site Primary Reaction
role: local_inflammatory_lesion
biological_scale: TISSUE
description: >-
R. conorii subsp. caspia infection after an R. pumilio bite produces a
primary reaction at the inoculation site, with regional lymph-node drainage
before or alongside disseminated Astrakhan fever.
downstream:
- target: Regional lymphadenitis
causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
description: >-
Local bite-site infection can drain to and inflame regional lymph nodes.
- target: Astrakhan Fever Microvascular Inflammation
causal_link_type: INDIRECT_KNOWN_INTERMEDIATES
description: >-
Local rickettsial infection can progress to the disseminated cutaneous and
systemic inflammatory syndrome.
evidence:
- reference: PMID:9324803
reference_title: "[The primary effect and characteristics of the course of a new tick-borne rickettsiosis--Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
Clinicomorphological characteristics are given of primary reaction at the
site of tick (Rhipicephalus pumilio) bite in new rickettsiosis spreading
in Astrakhan Province--Astrakhan fever.
explanation: >-
The Astrakhan fever clinical-morphologic report centers the primary
bite-site reaction after R. pumilio exposure.
- name: Astrakhan Fever Microvascular Inflammation
role: vascular_response
biological_scale: TISSUE
description: >-
Local and disseminated rickettsial infection inflames small cutaneous and
systemic vessels, producing the fever, conjunctival, lymph-node, hepatic,
rash, and hemodynamic manifestations reported in Astrakhan fever.
cell_types:
- preferred_term: vascular endothelial cell
term:
id: CL:0002139
label: endothelial cell of vascular tree
downstream:
- target: Febrile Astrakhan Fever Exanthem
causal_link_type: DIRECT
description: >-
Cutaneous microvascular injury creates the papular-hemorrhagic rash and
systemic febrile syndrome.
- target: Astrakhan Fever Cellular Immune Perturbation
causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
description: >-
Acute rickettsial infection is accompanied by transient shifts in T- and
B-cell compartments.
evidence:
- reference: PMID:9324803
reference_title: "[The primary effect and characteristics of the course of a new tick-borne rickettsiosis--Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The disease presented with long-term fever (body temperature 39-40
degrees C), intoxication, conjunctivitis, hepatomegaly, regional
lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial
hypotension.
explanation: >-
The primary-lesion report ties Astrakhan fever to a disseminated
inflammatory clinical syndrome after an R. pumilio bite-site reaction.
- reference: PMID:12459842
reference_title: "Cytokins in the pathogenesis of astrakhan spotted Fever and North Asian scrub typhus: problems of immunocorrection."
supports: SUPPORT
evidence_source: MODEL_ORGANISM
snippet: >-
Comparative study of interleukin-1 and tumor necrosis factor production
under conditions of experimental rickettsial infection caused by agents
of Astrakhan spotted fever and North Asian scrub typhus showed that
therapy with galavit reduced manifestations of the disease, decreased
mortality of experimental animals, and decreased the concentrations of
interleukin-1 and tumor necrosis factor to normal values.
explanation: >-
Experimental Astrakhan fever infection engaged the inflammatory cytokines
IL-1 and TNF in an animal model.
- name: Febrile Astrakhan Fever Exanthem
role: clinical_manifestation
biological_scale: ORGANISM
description: >-
Astrakhan fever manifests as a 39-40 degrees C febrile illness with a
disseminated roseolous papular-hemorrhagic rash and conjunctival, hepatic,
lymph-node, and blood-pressure involvement.
evidence:
- reference: PMID:9324803
reference_title: "[The primary effect and characteristics of the course of a new tick-borne rickettsiosis--Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The disease presented with long-term fever (body temperature 39-40
degrees C), intoxication, conjunctivitis, hepatomegaly, regional
lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial
hypotension.
explanation: >-
The clinical abstract enumerates the fever, rash, ocular, hepatic,
lymph-node, and vascular features of Astrakhan fever.
- name: Astrakhan Fever Cellular Immune Perturbation
role: immune_response
biological_scale: CELLULAR
description: >-
Moderate Astrakhan fever suppresses measured T- and B-cell immunity for
about two weeks, while severe disease prolongs that suppression to about
three weeks.
evidence:
- reference: PMID:12498120
reference_title: "[Status of cellular immunity in patients with Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
Examination of immunocompetent cells has revealed suppression of T- and
B-immunity for 2 weeks in moderate AF and 3 weeks in severe AF.
explanation: >-
The 75-patient cellular-immunity study reports a transient Astrakhan
fever-associated suppression of T- and B-cell compartments.
phenotypes:
- name: Fever
category: Constitutional
description: Astrakhan spotted fever produces high fever during acute illness.
phenotype_term:
preferred_term: Fever
term:
id: HP:0001945
label: Fever
evidence:
- reference: PMID:9324803
reference_title: "[The primary effect and characteristics of the course of a new tick-borne rickettsiosis--Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The disease presented with long-term fever (body temperature 39-40
degrees C), intoxication, conjunctivitis, hepatomegaly, regional
lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial
hypotension.
explanation: >-
The clinical report describes fever at 39-40 degrees C in Astrakhan fever.
- name: Maculopapular hemorrhagic rash
category: Dermatologic
description: >-
Astrakhan fever can cause a disseminated roseolous papular-hemorrhagic
eruption.
phenotype_term:
preferred_term: Maculopapular exanthema
term:
id: HP:0040186
label: Maculopapular exanthema
evidence:
- reference: PMID:9324803
reference_title: "[The primary effect and characteristics of the course of a new tick-borne rickettsiosis--Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The disease presented with long-term fever (body temperature 39-40
degrees C), intoxication, conjunctivitis, hepatomegaly, regional
lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial
hypotension.
explanation: >-
The source names the disseminated papular-hemorrhagic rash as a clinical
feature of Astrakhan fever.
- name: Conjunctivitis
category: Ophthalmologic
description: >-
Conjunctival inflammation occurs as part of the acute Astrakhan fever
syndrome.
phenotype_term:
preferred_term: Conjunctivitis
term:
id: HP:0000509
label: Conjunctivitis
evidence:
- reference: PMID:9324803
reference_title: "[The primary effect and characteristics of the course of a new tick-borne rickettsiosis--Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The disease presented with long-term fever (body temperature 39-40
degrees C), intoxication, conjunctivitis, hepatomegaly, regional
lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial
hypotension.
explanation: >-
The same clinical series lists conjunctivitis among Astrakhan fever
manifestations.
- name: Hepatomegaly
category: Gastrointestinal
description: Astrakhan fever can enlarge the liver during acute infection.
phenotype_term:
preferred_term: Hepatomegaly
term:
id: HP:0002240
label: Hepatomegaly
evidence:
- reference: PMID:9324803
reference_title: "[The primary effect and characteristics of the course of a new tick-borne rickettsiosis--Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The disease presented with long-term fever (body temperature 39-40
degrees C), intoxication, conjunctivitis, hepatomegaly, regional
lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial
hypotension.
explanation: >-
The report names hepatomegaly in the Astrakhan fever presentation.
- name: Regional lymphadenitis
category: Immune
description: >-
Draining lymph nodes can become regionally inflamed after the infected tick
bite.
phenotype_term:
preferred_term: Lymphadenitis
term:
id: HP:0002840
label: Lymphadenitis
evidence:
- reference: PMID:9324803
reference_title: "[The primary effect and characteristics of the course of a new tick-borne rickettsiosis--Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The disease presented with long-term fever (body temperature 39-40
degrees C), intoxication, conjunctivitis, hepatomegaly, regional
lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial
hypotension.
explanation: >-
Regional lymphadenitis is listed among the Astrakhan fever clinical
findings.
- name: Arterial hypotension
category: Cardiovascular
description: Acute Astrakhan fever can include low arterial blood pressure.
phenotype_term:
preferred_term: Hypotension
term:
id: HP:0002615
label: Hypotension
evidence:
- reference: PMID:9324803
reference_title: "[The primary effect and characteristics of the course of a new tick-borne rickettsiosis--Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The disease presented with long-term fever (body temperature 39-40
degrees C), intoxication, conjunctivitis, hepatomegaly, regional
lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial
hypotension.
explanation: >-
The clinical series reports arterial hypotension in Astrakhan fever.
diagnosis:
- name: Combined IgM and IgA serology
description: >-
Enzyme-linked immunosorbent assay serology can support Astrakhan rickettsial
fever diagnosis, and measurement of both IgM and IgA increased serologic
confirmation compared with IgM alone in a 185-patient Astrakhan-region
cohort.
diagnosis_term:
preferred_term: serologic testing
term:
id: NCIT:C25294
label: Laboratory Procedure
results: >-
Combined IgM and IgA antibody detection confirms more cases than IgM
detection alone.
evidence:
- reference: PMID:35467375
reference_title: >-
Diagnostic Value of IgA Antibody Measurement in Tick-Borne Spotted Fever
(Astrakhan Rickettsial Fever).
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
We investigated the diagnostic value of IgA antibody determination using
patient sera collected in the Astrakhan region of Russia, where an
isolated site of Astrakhan rickettsial fever (ARF) caused by Rickettsia
conorii subsp. caspia is located.
explanation: >-
The diagnostic cohort studied Astrakhan rickettsial fever from the endemic
Russian focus.
- reference: PMID:35467375
reference_title: >-
Diagnostic Value of IgA Antibody Measurement in Tick-Borne Spotted Fever
(Astrakhan Rickettsial Fever).
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The obtained data show that the determination of IgM alone allows for
serological confirmation of diagnosis in only 46.5% of cases but that the
determination of both IgM and IgA increases this rate to 66.5%.
explanation: >-
The Astrakhan-region study quantifies the gain from adding IgA to IgM
serology.
- name: Microimmunofluorescence and immunoblot serology
description: >-
Microimmunofluorescence and western immunoblotting detect IgG and IgM
responses in Astrakhan fever sera, but patient responses to the Astrakhan
strain and an Israelian spotted-fever-group isolate can be similar,
requiring care when interpreting isolate-level serology.
diagnosis_term:
preferred_term: serologic testing
term:
id: NCIT:C25294
label: Laboratory Procedure
results: >-
IgG and IgM antibodies to spotted-fever-group rickettsiae support
retrospective serologic identification with isolate-level cross-reactivity.
evidence:
- reference: PMID:8549703
reference_title: >-
Serologic response to rickettsial antigens in patients with Astrakhan
fever.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
Sera of patients with Astrakhan fever have been examined by
microimmunofluorescence and western immunoblotting to determine the
serologic responses to the Astrakhan strain and to R. conorii M-1 strain
and the Israelian isolate of SFG rickettsiae.
explanation: >-
The serologic study applied microimmunofluorescence and immunoblotting to
Astrakhan fever patient sera against related spotted-fever-group isolates.
- reference: PMID:8549703
reference_title: >-
Serologic response to rickettsial antigens in patients with Astrakhan
fever.
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: >-
The serologic response to specific rickettsial agent and to Israelian
isolate has been found to be similar, but was different of that to R.
conorii.
explanation: >-
Similar reactivity to the Astrakhan agent and the Israelian isolate
establishes a diagnostic cross-reaction that must be interpreted at
isolate level.
treatments:
- name: Empiric doxycycline therapy
description: >-
Doxycycline is the recommended treatment for tick-borne rickettsioses, and
an Astrakhan fever series reported better clinical efficiency for
doxycycline than for rifampicin.
therapeutic_modality: SMALL_MOLECULE
treatment_term:
preferred_term: Pharmacotherapy
term:
id: NCIT:C15986
label: Pharmacotherapy
therapeutic_agent:
- preferred_term: doxycycline
term:
id: CHEBI:50845
label: doxycycline
target_mechanisms:
- target: Obligate Intracytosolic Rickettsial Niche
treatment_effect: INHIBITS
description: >-
Doxycycline reaches the intracellular rickettsial niche and inhibits
bacterial protein synthesis in the susceptible pathogen.
evidence:
- reference: PMID:15109588
reference_title: Tick-borne rickettsioses in international travellers.
supports: SUPPORT
evidence_source: OTHER
quote_role: REVIEW_SYNTHESIS
snippet: >-
Doxycycline is the recommended treatment for tick-borne rickettsioses and
prevention is based on personal protective measures against tick bites
when travelling in endemic areas.
explanation: >-
The international-travel review states the group-level recommended
therapy for tick-borne rickettsioses.
- reference: PMID:12498120
reference_title: "[Status of cellular immunity in patients with Astrakhan fever]."
supports: SUPPORT
evidence_source: HUMAN_CLINICAL
snippet: "Doxicycline efficiency was higher than that of rifampicin."
explanation: >-
Despite the transliterated spelling in the abstract, the treatment series
directly compared doxycycline with rifampicin in Astrakhan fever and
favored doxycycline.
notes: >-
MONDO defines Astrakhan spotted fever by infection with Rickettsia conorii
subsp. caspia; this entry therefore binds the exact subspecies
NCBITaxon:302011 rather than the broader NCBITaxon:781 R. conorii parent used
in the older spotted-fever-group root entry.
Deep research results are used as seeds for research; they do not undergo the same validation as the main records and may contain errors. How we use deep research.
Create: Astrakhan spotted fever · 2026-09-28T10:54:02Z · View source
Created a de novo Astrakhan spotted fever entry from the Claude Code deep-research report and exact PMID caches. Bound MONDO:0024473 and NCBITaxon:302011, modeled Rhipicephalus tick transmission, curated a compact spotted-fever rickettsial pathophysiology chain, added Galimzianov-backed fever/rash/conjunctivitis/hepatomegaly/lymphadenitis/hypotension phenotypes, and added empiric doxycycline therapy. Generated the MONDO/NCBITaxon term-cache rows and PMID caches required by validation.
Target: Astrakhan spotted fever (MONDO:0024473) · Category: Infectious Disease · Report date: 2026-09-28
Scope note on sources. Astrakhan spotted fever (ASF) has a small literature, much of it Russian-language with English abstracts only. The surveillance numbers below come from one 1983–1988 prospective series (as summarized in the Parola 2005 review), one 2000–2020 registry summary (a 2021 conference abstract), and a 2022 serology study that quotes official annual counts. Quotations marked verbatim were copied from PubMed abstracts retrieved during this research; figures attributed to the 2024 China letter and the 2021 IJID abstract were read from indexed summaries because the publisher pages were paywalled, and should be re-verified against the full text before being used as evidence snippets.
Overview. Astrakhan spotted fever is a tick-borne spotted-fever-group (SFG) rickettsiosis caused by Rickettsia conorii subsp. caspia, a member of the R. conorii complex. It is endemic to the lower Volga delta and Caspian littoral (Astrakhan oblast and Kalmykia, Russia), transmitted chiefly by Rhipicephalus pumilio and the brown dog tick Rhipicephalus sanguineus, and presents as a summer febrile exanthem that resembles Mediterranean spotted fever (MSF) but with a notably lower frequency of inoculation eschar. The Kosovo tick study describes it as "a summer spotted fever resembling Mediterranean spotted fever, endemic in Astrakhan, a region of Russia located by the Caspian sea" (verbatim, PMID:12860620).
The disease was first noticed in the 1970s as a "viral exanthema of unknown etiology" and shown to be a rickettsiosis in the early 1990s: "The acute febrile disease with characteristic rash seen in Astrakhan region and named as 'viral exanthema of unknown etiology' was proved to be a spotted fever group rickettsiosis" (verbatim, Tarasevich 1991, PMID:1884783). Russian surveillance dates recognition to 1983: "Astrakhan spotted fever, caused by R. conorii subsp. caspia has been recognized since 1983" (verbatim, Tarasevich 2006, PMID:17114680).
Identifiers
| Resource | Identifier | Source |
|---|---|---|
| MONDO | MONDO:0024473 "Astrakhan spotted fever" | Monarch API (parent MONDO:0005677, Rickettsia conorii infectious disease) |
| DOID | DOID:0050041 | MONDO xref via Monarch |
| GARD | GARD:0025401 | MONDO xref via Monarch |
| MedGen / UMLS | MedGen 1814171 / UMLS C5574872 | MONDO xref via Monarch |
| Orphanet | No ORPHA xref present on the MONDO record | Monarch API |
| OMIM | Not applicable (infectious disease) | — |
| ICD-10 | A77.1 "Spotted fever due to Rickettsia conorii" is the applicable parent code; no ASF-specific code exists | Not verified against WHO this session; treat as a lead |
| MeSH | No dedicated descriptor found; indexed under "Boutonneuse Fever" / "Rickettsia Infections" | Inferred from PubMed indexing of the retrieved records |
| NCBI Taxonomy (agent) | NCBITaxon:302011 Rickettsia conorii subsp. caspia (rank: subspecies) | NCBI esummary |
| NCBI Taxonomy (parent species) | NCBITaxon:781 Rickettsia conorii | repo cache + NCBI |
Synonyms: Astrakhan fever; Astrakhan rickettsial fever (ARF, used by Russian and Chinese authors); Astrakhan fever rickettsiosis; historically "viral exanthema of unknown etiology" (Astrakhan). Agent synonyms: Astrakhan fever rickettsia (AFR); R. conorii Astrakhan strain; type strain A-167.
Nature of the information. All data are aggregated disease-level resources and case series, not individual EHR records.
Causal factor. Infection with R. conorii subsp. caspia following the bite of an infected Rhipicephalus tick. Taxonomy: Zhu et al. (2005) proposed "R. conorii subspecies caspia subsp. nov. (type strain = A-167)" on the basis of multilocus sequence typing, multi-spacer typing and mouse serotyping, noting that "strains within the R. conorii species show MST genotypic, serotypic, and epidemio-clinical dissimilarities" (verbatim, PMID:15766388). Earlier work had found the agent antigenically indistinguishable from the Israeli spotted fever rickettsia: "Astrakhan fever rickettsiae were found to be serologically and antigenically similar to Israeli spotted fever rickettsiae. Both of them probably belong to a single Rickettsia conorii pathotype complex. Only PFGE pattern analysis could clearly discriminate Astrakhan fever rickettsiae from other isolates" (verbatim, Eremeeva 1994, PMID:7985764; see also Drancourt 1992, PMID:1583342, a letter titled "Astrakhan fever rickettsia is identical to Israel tick typhus rickettsia").
Risk factors (environmental / behavioural). - Tick exposure and dog contact. In the 1983–1988 series, "Most of the patients had dogs and reported having contact with Rhipicephalus sanguineus dog ticks" (Parola 2005 review, PMID:16223955, summarizing Tarasevich). Tarasevich (1991) detected SFG rickettsiae "in 8 of 104 Rhipicephalus sanguineus ticks removed from dogs" (verbatim, PMID:1884783). - Season. 85% of cases occurred in summer, 43% in August alone (PMID:16223955). The 2019 serology cohort was collected May–October (PMID:35467375); the four Chinese cases all began in July 2023 (PMID:38462076). - Rural residence in the Volga delta / Caspian steppe. Early cases were "in patients of rural areas" (PMID:16223955). The 2021 registry abstract reports spread from Astrakhan city plus 3 districts in 1993 to all 11 districts of the oblast by 2013 (IJID 2021 abstract, PII S1201-9712(21)01194-2). - Age and sex. Adults (94%) and males (61%) predominated in 1983–1988 (PMID:16223955). The 2019 cohort spanned ages 1–88 (mean 45) (PMC9241626). - Vector abundance. The 2021 abstract states the rise in incidence "begins when the abundance index of R. pumilio ticks reaches its maximum" (indexed summary; verify against full text).
Genetic risk / protective factors. None reported for ASF. No GWAS, ClinVar, or ClinGen data exist. This is expected for an acute zoonotic infection.
Protective factors. Tick avoidance and prompt tick removal (generic to SFG rickettsioses; CDC 2016 guidance, PMID:27172113). No vaccine exists (PMID:24059918: "No suitable vaccines for human use are currently available to prevent rickettsial diseases", verbatim).
Gene–environment interactions. Not studied.
Frequencies are from the 1983–1988 prospective series of 321 cases (as summarized in PMID:16223955) unless stated otherwise. HPO identifiers below were read from the repository's HP term cache (cache/hp/terms.csv) during this session.
| Phenotype | Type | Frequency | Onset / course | HPO suggestion |
|---|---|---|---|---|
| Fever, high (39–40 °C), prolonged | Sign | 94% | Acute, sustained over days to ~2 weeks | HP:0001945 Fever |
| Maculopapular rash, disseminated, may be roseolous-papular-hemorrhagic | Sign | 94% (with fever) | Appears early, generalized incl. extremities | HP:0040186 Maculopapular exanthema; HP:0000988 Skin rash |
| Hemorrhagic/petechial component of rash | Sign | Reported ("papular-hemorrhagic", PMID:9324803); % not given | — | HP:0000967 Petechiae |
| Inoculation eschar (tache noire), usually single | Sign | 23% | At bite site, precedes fever | HP:0200042 Skin ulcer (closest available; no HPO eschar term) |
| Conjunctivitis | Sign | 32% | Early | HP:0000509 Conjunctivitis |
| Regional lymphadenitis / adenopathy | Sign | Reported; % not given | Early, near bite site | HP:0002716 Lymphadenopathy |
| Hepatomegaly | Sign | Reported; % not given | — | HP:0002240 Hepatomegaly |
| Arterial hypotension | Sign | Reported; % not given | Acute phase | HP:0002615 Hypotension |
| "Intoxication" (malaise, headache, myalgia) | Symptom | Reported qualitatively | Acute phase | HP:0012378 Fatigue; HP:0002315 Headache; HP:0003326 Myalgia |
| Chills | Symptom | Typical of SFG rickettsioses; not quantified for ASF | — | HP:0025143 Chills |
| Transient T- and B-lymphocyte suppression | Laboratory | Observed in 75 patients | 2 weeks (moderate) / 3 weeks (severe) | No specific HPO term; describe in biochemical: |
Supporting quotes (verbatim): - "The disease presented with long-term fever (body temperature 39-40 degrees C), intoxication, conjunctivitis, hepatomegaly, regional lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial hypotension." (Galimzianov 1996, PMID:9324803) - "the
Target: Astrakhan spotted fever (MONDO:0024473) · Category: Infectious Disease · Report date: 2026-09-28
Scope note on sources. Astrakhan spotted fever (ASF) has a small literature, much of it Russian-language with English abstracts only. The surveillance numbers below come from one 1983–1988 prospective series (as summarized in the Parola 2005 review), one 2000–2020 registry summary (a 2021 conference abstract), and a 2022 serology study that quotes official annual counts. Quotations marked verbatim were copied from PubMed abstracts retrieved during this research; figures attributed to the 2024 China letter and the 2021 IJID abstract were read from indexed summaries because the publisher pages were paywalled, and should be re-verified against the full text before being used as evidence snippets.
Overview. Astrakhan spotted fever is a tick-borne spotted-fever-group (SFG) rickettsiosis caused by Rickettsia conorii subsp. caspia, a member of the R. conorii complex. It is endemic to the lower Volga delta and Caspian littoral (Astrakhan oblast and Kalmykia, Russia), transmitted chiefly by Rhipicephalus pumilio and the brown dog tick Rhipicephalus sanguineus, and presents as a summer febrile exanthem that resembles Mediterranean spotted fever (MSF) but with a notably lower frequency of inoculation eschar. The Kosovo tick study describes it as "a summer spotted fever resembling Mediterranean spotted fever, endemic in Astrakhan, a region of Russia located by the Caspian sea" (verbatim, PMID:12860620).
The disease was first noticed in the 1970s as a "viral exanthema of unknown etiology" and shown to be a rickettsiosis in the early 1990s: "The acute febrile disease with characteristic rash seen in Astrakhan region and named as 'viral exanthema of unknown etiology' was proved to be a spotted fever group rickettsiosis" (verbatim, Tarasevich 1991, PMID:1884783). Russian surveillance dates recognition to 1983: "Astrakhan spotted fever, caused by R. conorii subsp. caspia has been recognized since 1983" (verbatim, Tarasevich 2006, PMID:17114680).
Identifiers
| Resource | Identifier | Source |
|---|---|---|
| MONDO | MONDO:0024473 "Astrakhan spotted fever" | Monarch API (parent MONDO:0005677, Rickettsia conorii infectious disease) |
| DOID | DOID:0050041 | MONDO xref via Monarch |
| GARD | GARD:0025401 | MONDO xref via Monarch |
| MedGen / UMLS | MedGen 1814171 / UMLS C5574872 | MONDO xref via Monarch |
| Orphanet | No ORPHA xref present on the MONDO record | Monarch API |
| OMIM | Not applicable (infectious disease) | — |
| ICD-10 | A77.1 "Spotted fever due to Rickettsia conorii" is the applicable parent code; no ASF-specific code exists | Not verified against WHO this session; treat as a lead |
| MeSH | No dedicated descriptor found; indexed under "Boutonneuse Fever" / "Rickettsia Infections" | Inferred from PubMed indexing of the retrieved records |
| NCBI Taxonomy (agent) | NCBITaxon:302011 Rickettsia conorii subsp. caspia (rank: subspecies) | NCBI esummary |
| NCBI Taxonomy (parent species) | NCBITaxon:781 Rickettsia conorii | repo cache + NCBI |
Synonyms: Astrakhan fever; Astrakhan rickettsial fever (ARF, used by Russian and Chinese authors); Astrakhan fever rickettsiosis; historically "viral exanthema of unknown etiology" (Astrakhan). Agent synonyms: Astrakhan fever rickettsia (AFR); R. conorii Astrakhan strain; type strain A-167.
Nature of the information. All data are aggregated disease-level resources and case series, not individual EHR records.
Causal factor. Infection with R. conorii subsp. caspia following the bite of an infected Rhipicephalus tick. Taxonomy: Zhu et al. (2005) proposed "R. conorii subspecies caspia subsp. nov. (type strain = A-167)" on the basis of multilocus sequence typing, multi-spacer typing and mouse serotyping, noting that "strains within the R. conorii species show MST genotypic, serotypic, and epidemio-clinical dissimilarities" (verbatim, PMID:15766388). Earlier work had found the agent antigenically indistinguishable from the Israeli spotted fever rickettsia: "Astrakhan fever rickettsiae were found to be serologically and antigenically similar to Israeli spotted fever rickettsiae. Both of them probably belong to a single Rickettsia conorii pathotype complex. Only PFGE pattern analysis could clearly discriminate Astrakhan fever rickettsiae from other isolates" (verbatim, Eremeeva 1994, PMID:7985764; see also Drancourt 1992, PMID:1583342, a letter titled "Astrakhan fever rickettsia is identical to Israel tick typhus rickettsia").
Risk factors (environmental / behavioural). - Tick exposure and dog contact. In the 1983–1988 series, "Most of the patients had dogs and reported having contact with Rhipicephalus sanguineus dog ticks" (Parola 2005 review, PMID:16223955, summarizing Tarasevich). Tarasevich (1991) detected SFG rickettsiae "in 8 of 104 Rhipicephalus sanguineus ticks removed from dogs" (verbatim, PMID:1884783). - Season. 85% of cases occurred in summer, 43% in August alone (PMID:16223955). The 2019 serology cohort was collected May–October (PMID:35467375); the four Chinese cases all began in July 2023 (PMID:38462076). - Rural residence in the Volga delta / Caspian steppe. Early cases were "in patients of rural areas" (PMID:16223955). The 2021 registry abstract reports spread from Astrakhan city plus 3 districts in 1993 to all 11 districts of the oblast by 2013 (IJID 2021 abstract, PII S1201-9712(21)01194-2). - Age and sex. Adults (94%) and males (61%) predominated in 1983–1988 (PMID:16223955). The 2019 cohort spanned ages 1–88 (mean 45) (PMC9241626). - Vector abundance. The 2021 abstract states the rise in incidence "begins when the abundance index of R. pumilio ticks reaches its maximum" (indexed summary; verify against full text).
Genetic risk / protective factors. None reported for ASF. No GWAS, ClinVar, or ClinGen data exist. This is expected for an acute zoonotic infection.
Protective factors. Tick avoidance and prompt tick removal (generic to SFG rickettsioses; CDC 2016 guidance, PMID:27172113). No vaccine exists (PMID:24059918: "No suitable vaccines for human use are currently available to prevent rickettsial diseases", verbatim).
Gene–environment interactions. Not studied.
Frequencies are from the 1983–1988 prospective series of 321 cases (as summarized in PMID:16223955) unless stated otherwise. HPO identifiers below were read from the repository's HP term cache (cache/hp/terms.csv) during this session.
| Phenotype | Type | Frequency | Onset / course | HPO suggestion |
|---|---|---|---|---|
| Fever, high (39–40 °C), prolonged | Sign | 94% | Acute, sustained over days to ~2 weeks | HP:0001945 Fever |
| Maculopapular rash, disseminated, may be roseolous-papular-hemorrhagic | Sign | 94% (with fever) | Appears early, generalized incl. extremities | HP:0040186 Maculopapular exanthema; HP:0000988 Skin rash |
| Hemorrhagic/petechial component of rash | Sign | Reported ("papular-hemorrhagic", PMID:9324803); % not given | — | HP:0000967 Petechiae |
| Inoculation eschar (tache noire), usually single | Sign | 23% | At bite site, precedes fever | HP:0200042 Skin ulcer (closest available; no HPO eschar term) |
| Conjunctivitis | Sign | 32% | Early | HP:0000509 Conjunctivitis |
| Regional lymphadenitis / adenopathy | Sign | Reported; % not given | Early, near bite site | HP:0002716 Lymphadenopathy |
| Hepatomegaly | Sign | Reported; % not given | — | HP:0002240 Hepatomegaly |
| Arterial hypotension | Sign | Reported; % not given | Acute phase | HP:0002615 Hypotension |
| "Intoxication" (malaise, headache, myalgia) | Symptom | Reported qualitatively | Acute phase | HP:0012378 Fatigue; HP:0002315 Headache; HP:0003326 Myalgia |
| Chills | Symptom | Typical of SFG rickettsioses; not quantified for ASF | — | HP:0025143 Chills |
| Transient T- and B-lymphocyte suppression | Laboratory | Observed in 75 patients | 2 weeks (moderate) / 3 weeks (severe) | No specific HPO term; describe in biochemical: |
Supporting quotes (verbatim): - "The disease presented with long-term fever (body temperature 39-40 degrees C), intoxication, conjunctivitis, hepatomegaly, regional lymphadenitis, disseminated roseolous papular-hemorrhagic rash, arterial hypotension." (Galimzianov 1996, PMID:9324803) - "the presence of a tache noire was reported in only 23% of the patients" (Parola 2005, PMID:16223955). - "Examination of immunocompetent cells has revealed suppression of T- and B-immunity for 2 weeks in moderate AF and 3 weeks in severe AF. The number of T-helpers was low for 3 weeks while of T-suppressors rose beginning from week 2." (Kasimova 2002, PMID:12498120)
Distinguishing feature vs MSF. The low eschar rate (23%) is the clinically important contrast with Mediterranean spotted fever, where the tache noire is usual. This shifts differential weight toward rash-plus-fever presentations without a findable bite site.
Severity and quality of life. Severe disease accounted for 5.3% of Russian cases and case fatality is stated as approximately 1–2%, with a first reported death in 2013 (figures cited in the 2024 China letter, PMID:38462076; read from indexed summaries, not the full text). No EQ-5D, SF-36 or PROMIS data exist for ASF; as a self-limited acute illness it has no documented chronic quality-of-life burden.
Host genetics: not applicable. ASF has no causal genes, pathogenic variants, modifier genes, epigenetic signature or chromosomal abnormality. No ClinVar, HGMD, gnomAD or DECIPHER content pertains.
Pathogen genomics. The genome of R. conorii subsp. caspia strain A-167 was sequenced in 2012 (Sentausa et al., PMID:22887666, J Bacteriol): draft genome of 1,260,331 bases in 25 contigs at ~20× coverage, "a total complement of 1,210 genes (1,636 open reading frames [ORFs])" (verbatim), 33% GC, deposited as GenBank AJUR00000000. Among predicted genes, "820 (67.8%) are complete genes, 229 (18.9%) are split into two to 12 ORFs, and 78 (6.5%) are present only as fragments" (verbatim) — the split/fragmented pattern is the genome-reduction signature typical of Rickettsia.
Typing loci used for identification. 16S rDNA, gltA (citrate synthase), ompA (rOmpA), ompB, sca4, and the 23S–5S intergenic spacer. Pairwise similarity across the four R. conorii subspecies ranged 98.2–100% depending on locus, with ompA and ompB the most discriminating (PMID:15766388). Historic methodology: Roux 1997 (gltA, PMID:9103608), Fournier 1998 (rOmpA, PMID:9734038), Roux 1995 (16S rDNA, PMID:8525055).
Suggested annotations: the surface adhesins rOmpA and rOmpB (UniProt R. conorii entries; Sca family autotransporters) and Sca2/RickA for actin-based motility are the functionally characterized proteins, all studied in R. conorii sensu lato rather than in subsp. caspia specifically.
Infectious agent. Rickettsia conorii subsp. caspia (NCBITaxon:302011), an obligate intracellular Gram-negative alphaproteobacterium of the spotted fever group.
Vectors. - Rhipicephalus pumilio (NCBITaxon:127007) — the principal Astrakhan vector; infection prevalence 3% in Astrakhan-region ticks: "Rh. pumilio from the Astrakhan region were infected with ... the Astrakhan fever agent (3%)" (verbatim, Rydkina 1999, PMID:10603217). The primary-lesion study attributes the bite to R. pumilio (PMID:9324803). - Rhipicephalus sanguineus (NCBITaxon:34632), the brown dog tick — vector in Kosovo, France and Zambia; also implicated by dog contact in Astrakhan.
Reservoirs and hosts. Domestic dogs (Canis lupus familiaris, NCBITaxon:9615) are the principal tick host linking vector to humans. I found no published evidence for a hedgehog or rodent reservoir specific to R. conorii subsp. caspia; a Kazakhstan rodent survey detected R. raoultii, R. slovaca and R. conorii but did not report subsp. caspia in rodents (PMID:36050456).
Geographic distribution beyond Astrakhan.
| Location | Finding | Citation |
|---|---|---|
| Astrakhan oblast and Kalmykia, Russia | Endemic focus, Caspian/Volga delta | PMID:17114680; PMID:12860620 |
| Kosovo | Detected in 4 R. sanguineus (3 from dogs, 1 from a soldier); "Our study demonstrates, for the first time, the presence of Astrakhan fever rickettsia in ticks outside Russia" (verbatim) | PMID:12860620 |
| Chad | Isolate from a febrile traveller, 99.5–99.7% identical across 16S/gltA/ompA; "The Chad isolate should be considered a variant of Astrakhan fever rickettsia" (verbatim) | PMID:12860619 |
| Southern France | 9 of 22 household R. sanguineus positive, "marking the first documentation of this subspecies in France" (verbatim), in an urban family cluster also involving R. massiliae | PMID:23140893 |
| Zambia | One tick of 1,465 (0.06%); one of 1,254 Rh. sanguineus (0.07%) | PMID:28986641 |
| Kazakhstan | Reported as circulating, per secondary statement in a rodent survey; not detected by that study itself | PMID:36050456 |
| Xinjiang, China | Four laboratory-confirmed human cases, July 2023, first R. conorii subsp. caspia infections reported in East Asia; Rh. sanguineus and Rh. pumilio present at 1.7% and 0.6% prevalence | PMID:38462076 (read from indexed summaries) |
Non-infectious environmental and lifestyle factors. None established beyond outdoor/rural exposure, dog ownership and season. No toxicological (CTD, EPA) contribution.
Important caveat. No mechanistic study has been performed on R. conorii subsp. caspia itself apart from cell-culture growth experiments. The chain below is the established SFG rickettsiosis mechanism, documented mainly for R. conorii sensu lato and R. rickettsii, applied to ASF by subspecies membership. Every step from 3 onward should be curated as directness: INDIRECT for ASF, or cited to the pan-rickettsial reviews (Walker 2008, PMID:18414502; Sahni 2013, PMID:24059918) with evidence_source: OTHER or IN_VITRO as appropriate. The two ASF-specific mechanistic observations are the primary-lesion histology (PMID:9324803) and the cytokine/cellular-immunity studies (PMID:12459842, PMID:12498120).
Ordered causal chain
Ontology suggestions (identifiers verified against the repository term caches this session)
| Concept | Term |
|---|---|
| Host-cell invasion by the bacterium | GO:0046718 symbiont entry into host cell |
| Inflammatory response | GO:0006954 inflammatory response |
| Innate immune response | GO:0045087 innate immune response |
| Cytokine production | GO:0001816 cytokine production |
| IL-1 production | GO:0032612 interleukin-1 production |
| TNF production | GO:0032640 tumor necrosis factor production |
| Response to bacterium | GO:0009617 response to bacterium |
| Apoptosis (endothelial) | GO:0006915 apoptotic process |
| Coagulation activation | GO:0007596 blood coagulation |
| Primary target cell | CL:0000115 endothelial cell; CL:0000071 blood vessel endothelial cell; CL:0002139 endothelial cell of vascular tree |
| Recruited cells | CL:0000775 neutrophil; CL:0000235 macrophage; CL:0000576 monocyte |
Molecular profiling. No transcriptomic, proteomic, metabolomic, lipidomic, single-cell or spatial data exist for ASF. No GEO, PRIDE, MetaboLights or DepMap datasets were found for R. conorii subsp. caspia. This is a real and total gap, not an omission of this report.
Inheritance: not applicable. ASF is an acquired infection with no heritable component, no penetrance/expressivity/anticipation/mosaicism/founder-effect/carrier-frequency parameters.
Epidemiology
| Measure | Value | Source |
|---|---|---|
| Registered cases, Astrakhan region, 2000–2020 | 4,894 | IJID 2021 abstract, PII S1201-9712(21)01194-2 (indexed summary) |
| Average long-term incidence, Astrakhan region | 23.18 ± 1.5 per 100,000 population | Same |
| Annual national cases, Russia | ~200–300 | PMC9241626 |
| Cases by year (Russia) | 295 (2014), 314 (2015), 299 (2016), 176 (2017), 290 (2018) | PMC9241626 |
| Severe disease fraction | 5.3% | Cited in PMID:38462076 (indexed summary) |
| Case fatality | ~1–2%; first reported death 2013 | Cited in PMID:38462076 (indexed summary) |
| Seroprevalence, healthy residents of endemic areas (1991) | 5.1% of 429 sera positive at titre 20–40 | PMID:1884783 (verbatim) |
For dismech Prevalence records, the 23.18 per 100,000 figure is a regional ANNUAL_INCIDENCE averaged over 2000–2020 and needs rate_denominator: POPULATION_PER_YEAR; the ~200–300 national annual counts are CASES_IN_LITERATURE-adjacent registry counts, not a rate.
Demographics. Male predominance (61%) and adult predominance (94%) in the 1983–1988 series (PMID:16223955) most plausibly reflect exposure rather than susceptibility. Sex ratio ≈ 1.6:1 male:female.
Geographic trend. Endemic area expanded within Astrakhan oblast from the city plus 3 districts (1993) to 9 rural districts plus the city (1999) to all 11 districts (2013), with incidence peaks in 2000, 2002, 2005–2007 and a maximum in 2013 tracking R. pumilio abundance (IJID 2021 abstract, indexed summary).
Serology (the mainstay). - Microimmunofluorescence (MIF) against SFG antigens. ASF sera react to the homologous Astrakhan strain and to the Israeli isolate similarly, and differently from R. conorii Malish: "The serologic response to specific rickettsial agent and to Israelian isolate has been found to be similar, but was different of that to R. conorii. Immunoglobulin G (IgG) and IgM antibodies were detected in most sera and were directed against the lipopolysaccharide" (verbatim, PMID:8549703). - ELISA IgM alone is insufficient. In 185 patients, "the determination of IgM alone allows for serological confirmation of diagnosis in only 46.5% of cases but ... the determination of both IgM and IgA increases this rate to 66.5%" (verbatim, PMID:35467375). IgM recognized both LPS and proteins; IgA predominantly proteins. This is the most actionable recent diagnostic finding for ASF and argues for adding IgA to the panel. - Complement fixation was used historically, cross-reacting across R. conorii, R. akari and R. sibirica at titres 20–640 (PMID:1884783) — insufficiently specific by modern standards. - Retrospective serosurveillance in high-risk areas: Chekanova 2019, PMID:31200408.
Molecular. - PCR amplification and sequencing of gltA, ompA, 16S rDNA, ompB, sca4 and the 23S–5S spacer distinguishes subspecies (PMID:12860619, PMID:12860620, PMID:28986641). - Suicide PCR on skin biopsy specimens is validated for rickettsioses generally (Fournier 2004, PMID:15297478) and is the route to a diagnosis from an eschar or rash biopsy. - Real-time pan-Rickettsia PCR for screening, with MLST confirmation.
Culture. Isolation in cell culture or guinea pigs is possible but slow, low-yield and biosafety-restricted; early attempts recovered rickettsiae in 2 of 12 cell-culture samples and seroconverted 4 of 8 guinea pigs (PMID:1884783). Strains A-108 and A-167 came from R. pumilio haemolymph (PMID:7985764).
Laboratory findings. Cellular immunology shows transient lymphopenia-like suppression with neutrophil increase from week 2–3 (PMID:12498120). Routine haematological and hepatic abnormality frequencies for ASF were not available in the retrieved abstracts.
Imaging, electrophysiology, functional tests: no role.
Genetic testing: not applicable (host).
Differential diagnosis. Mediterranean spotted fever (R. conorii subsp. conorii), Israeli spotted fever (subsp. israelensis, serologically near-identical — the key laboratory pitfall), Siberian tick typhus (R. sibirica), R. massiliae and R. aeschlimannii infection, Crimean-Congo hemorrhagic fever (co-circulating in the Caspian region and a critical rule-out given the hemorrhagic rash), West Nile fever, hemorrhagic fever with renal syndrome, and non-rickettsial viral exanthems. The 2022 study makes the general point: "The symptoms of this bacterial infection are similar to those of viral infection, and thus, diagnostic accuracy has special clinical importance" (verbatim, PMID:35467375). Butenko 1995 (PMID:7476689) treats arbovirus infections, HFRS and Astrakhan fever together as the regional differential.
Screening. No population screening. Surveillance is clinician-reported case notification plus tick-abundance monitoring.
Doxycycline is the treatment of choice. The CDC recommendation for tickborne rickettsial disease is explicit: "doxycycline is the treatment of choice for suspected tickborne rickettsial diseases in adults and children" (verbatim, PMID:27172113). For ASF specifically, a comparative Russian series concluded "Doxycycline efficiency was higher than that of rifampicin" (verbatim, PMID:12498120) — a direct head-to-head observation in ASF patients and the strongest disease-specific therapeutic evidence available.
| Agent | Role | CHEBI (repo cache) | NCIT |
|---|---|---|---|
| Doxycycline | First line | CHEBI:50845 | Pharmacotherapy NCIT:C15986 with therapeutic_agent bound to doxycycline |
| Rifampicin | Used in Russian series, less effective than doxycycline | CHEBI:28077 | NCIT:C15986 |
| Chloramphenicol | Historical alternative for SFG rickettsioses | CHEBI:17698 | NCIT:C15986 |
| Azithromycin / ciprofloxacin | Alternatives in MSF literature; no ASF-specific data | CHEBI:2955 / CHEBI:100241 | NCIT:C15986 |
| Supportive care | Fluids for hypotension, antipyresis | — | NCIT:C15747 Supportive Care |
The NCIT identifiers above were not resolvable in this worktree's cache/ncit/terms.csv during this session (the grep returned nothing), so each must be verified with just validate-terms before being written into a KB entry. Per the repository's term contract, do not commit an NCIT CURIE from this table without that lookup.
Adjunctive interferon — historical, and not recommended. Galimzianov 1996 reported that "Adjuvant use of interferons in basic treatment of Astrakhan fever elevates its efficacy" with alpha-2 at 15,000–25,000 IU/kg/day and gamma at 1,500–2,500 IU/kg/day, while noting that "Interferons induce side effects early in the course: intensification of hyperthermia and pains" (verbatim, PMID:8771664). This is a single uncontrolled 1996 report and has no modern support; curate it as historical practice, not current therapy.
Immunomodulation in animals. Galavit reduced IL-1/TNF and mortality in experimental ASF infection (PMID:12459842) — evidence_source: MODEL_ORGANISM, no human translation.
In vitro antimicrobial work. Wild thyme and bergamot essential oils inhibited R. conorii caspia growth in Vero cells (PMID:30316918); chitosan, selenium and silver nanoparticles showed anti-rickettsial activity in Vero cells (PMID:41011786, 2025). Both are IN_VITRO and pre-clinical.
Not applicable: gene therapy, cell therapy, RNA therapeutics, targeted therapy, immunotherapy, surgery, rehabilitation. No registered clinical trials for ASF were found; a ClinicalTrials.gov query was not run this session and the absence should be confirmed before asserting it in an entry.
Pharmacogenomics: none described.
evidence_source: IN_VITRO.modeled_mechanisms link for these systems should carry fidelity: LOW or UNKNOWN, model_scale: MOLECULAR or CELLULAR for the Vero work, and an explicit divergences entry of type SPECIES_MISMATCH (guinea pig, mouse) or BOUNDARY_OMISSION (Vero cells contain no vasculature, no immune compartment, and cannot report rash or hypotension).Verified PMIDs with abstracts retrieved this session, suitable for just fetch-reference:
| PMID | Short description | Best use |
|---|---|---|
| 15766388 | Zhu 2005, subspecies proposal, type strain A-167 | Taxonomy, agent identity |
| 1884783 | Tarasevich 1991, first characterization, seroprevalence 5.1%, ticks on dogs | History, epidemiology, vector |
| 1670806 | Tarasevich 1991 Lancet letter (no abstract) | Historical citation only |
| 7985764 | Eremeeva 1994, A-108/A-167 from R. pumilio, identity with ISF | Agent, vector |
| 1583342 | Drancourt 1992 letter (no abstract) | Historical |
| 8549703 | Eremeeva 1995, MIF/immunoblot, anti-LPS IgG/IgM | Diagnostics |
| 9324803 | Galimzianov 1996, primary lesion and clinical picture | Phenotypes, pathophysiology |
| 8771664 | Galimzianov 1996, interferon adjuvant | Treatment (historical) |
| 12498120 | Kasimova 2002, cellular immunity, doxycycline > rifampicin | Treatment, immunopathology |
| 12459842 | Nelyubov 2002, IL-1/TNF, galavit, animal model | Mechanism (MODEL_ORGANISM) |
| 10603217 | Rydkina 1999, 3% infection in R. pumilio | Vector |
| 12860619 | Fournier 2003, Chad isolate | Geography |
| 12860620 | Fournier 2003, Kosovo ticks | Geography, vector |
| 23140893 | Renvoisé 2012, French urban family cluster | Geography, prevention |
| 28986641 | Chitimia-Dobler 2017, Zambia, 0.06% | Geography |
| 22887666 | Sentausa 2012, genome A-167, AJUR00000000 | Pathogen genomics |
| 35467375 | Smirnova 2022, IgA raises confirmation 46.5% → 66.5% | Diagnostics |
| 17114680 | Tarasevich 2006, recognized since 1983 | History, Russian surveillance |
| 17266709 | Brouqui 2007, European SFG overview | Context |
| 33143199 | Malkhazova 2020, Russian natural-focal EID mapping | Epidemiology context |
| 27172113 | CDC 2016, doxycycline is treatment of choice | Treatment |
| 18414502 | Walker 2008, endothelial infection and early events | Mechanism (indirect) |
| 24059918 | Sahni 2013, rickettsial pathogenesis and immunity | Mechanism (indirect) |
| 16223955 | Parola 2005, review carrying the 321-case series figures | Phenotype frequencies |
| 38462076 | Teng 2024, four cases in Xinjiang, first in East Asia | Geography, severity figures |
| 31053085 | Turebekov 2019, Kazakhstan ticks (caspia not found) | Negative/context |
| 36050456 | Kazakhstan rodents (caspia not found in rodents) | Negative/context |
| 39065062 | Karachay-Cherkessia ticks (caspia not found) | Negative/context |
Figures needing full-text verification before use as snippets: the 321-case series percentages (94% adults, 61% male, 85% summer, 43% August, 94% fever with rash, 23% eschar, 32% conjunctivitis) read from the Parola 2005 review rather than the primary Russian source; the 4,894 cases and 23.18 ± 1.5 per 100,000 from the 2021 IJID conference abstract; and the 5.3% severe / 1–2% mortality / first-death-2013 figures cited in the 2024 China letter. The last three publisher pages returned 403 or CAPTCHA this session.
Checked with linkml-reference-validator 0.3.0rc3.
| Outcome | Count |
|---|---|
| References checked | 38 |
| Resolved | 38 |
| Unresolved (possible confabulation) | 0 |
| Unverifiable | 0 |
| Quoted claims checked | 31 |
| Quoted claims found in source | 25 |
| Quoted claims not found in source | 6 |
| Quoted claims with nothing to check against | 2 |
| References weighed for topical relevance | 38 |
| On topic | 19 |
| Off topic | 0 |
Searched the abstract, any retrieved full text, and the title. A quote drawn from a part of the paper that was not retrieved will appear here too, so check before treating one as invented:
Every one of these was searched against an abstract alone, with no full text retrieved - marked abstract only below. Where full text can be fetched, re-running with it will settle them; where the source publishes only a summary to PubMed, as GeneReviews chapters do, it will not, and the quote has to be checked by hand against the chapter itself.
PMID:16223955 (abstract only): "Most of the patients had dogs and reported having contact with Rhipicephalus sanguineus dog ticks"PMID:16223955 (abstract only): "in patients of rural areas"PMID:16223955 (abstract only): "Most of the patients had dogs and reported having contact with Rhipicephalus sanguineus dog ticks"PMID:16223955 (abstract only): "in patients of rural areas"PMID:16223955 (abstract only): "the presence of a tache noire was reported in only 23% of the patients"PMID:12498120 (abstract only): "Doxycycline efficiency was higher than that of rifampicin"There was no text to compare these against, so they are neither confirmed nor contradicted:
PMID:1583342: "Astrakhan fever rickettsiae were found to be serologically and antigenically similar to Israeli spotted fever rickettsiae. Both of them probably belong to a single Rickettsia conorii pathotype complex. Only PFGE pattern analysis could clearly discriminate Astrakhan fever rickettsiae from other isolates"PMID:1583342: "Astrakhan fever rickettsiae were found to be serologically and antigenically similar to Israeli spotted fever rickettsiae. Both of them probably belong to a single Rickettsia conorii pathotype complex. Only PFGE pattern analysis could clearly discriminate Astrakhan fever rickettsiae from other isolates"Checked with linkml-term-validator 0.4.5, through the ols: adapter.
| Outcome | Count |
|---|---|
| Terms checked | 54 |
| Resolved | 53 |
| Unresolved (possible confabulation) | 0 |
| Obsolete | 0 |
| Unverifiable | 1 |
| Terms whose name was checked | 8 |
| Terms named correctly | 2 |
| Terms named as a different term | 6 |
These identifiers resolve, so nothing about them looks wrong, and the ontology calls them something unrelated to what the report calls them. That usually means the identifier is not the one the sentence needs:
MONDO:0024473 (7 mentions) - the report calls it "Monarch"; MONDO calls it Astrakhan spotted feverDOID:0050041 (2 mentions) - the report calls it "DOID"; DOID calls it Astrakhan spotted feverNCBITaxon:302011 (3 mentions) - the report calls it "caspia"; NCBITaxon calls it Rickettsia conorii subsp. caspiaCHEBI:50845 (1 mention) - the report calls it "First line"; CHEBI calls it doxycyclineCHEBI:28077 (1 mention) - the report calls it "Used in Russian series, less effective than doxycycline"; CHEBI calls it rifampicinCHEBI:17698 (1 mention) - the report calls it "Historical alternative for SFG rickettsioses"; CHEBI calls it chloramphenicolTerms carrying these prefixes were not checked either way, because no configured ontology covers them. An unrecognised prefix may name an ontology this run could not reach as easily as one that does not exist, so nothing here is evidence of fabrication: GARD.