| Field | Value | Notes / Evidence |
|---|---|---|
| Preferred disease name | Legionnaires' disease | Pneumonic form of legionellosis caused predominantly by *Legionella pneumophila* (pqac-00000005, pqac-00000022) |
| Broader related disease term | legionellosis | Includes Legionnaires' disease and the non-pneumonic form, Pontiac fever (pqac-00000006, pqac-00000007) |
| MONDO ID | MONDO:0005824 | OpenTargets returned MONDO_0005824 for Legionnaires' disease (pqac-00000000) |
| Related MONDO ID | MONDO:0005823 | OpenTargets returned MONDO_0005823 for legionellosis (pqac-00000000) |
| ICD-10-CM | A48.1 | Standard ICD-10 code for Legionnaires' disease |
| ICD-11 | 1C32 | ICD-11 category for Legionnaires disease |
| MeSH | D007876 | MeSH descriptor for Legionnaires' Disease |
| Disease category | Infectious disease; bacterial pneumonia; waterborne/aerosol-transmitted environmental infection | Recent reviews describe LD as a waterborne pneumonia and a major cause of severe community-acquired pneumonia (pqac-00000005, pqac-00000007) |
| Primary causative agent | *Legionella pneumophila* | Accounts for >90% of cases in multiple epidemiologic summaries; serogroup 1 predominates (pqac-00000005, pqac-00000006) |
| Other clinically relevant species | *L. longbeachae* and other *Legionella* spp. | Non-*pneumophila* species also cause disease and are often missed by standard UAT-focused diagnosis (pqac-00000018) |
| Common synonyms | Legionella pneumonia; Legion fever; legionellosis | “Legionellosis” is the umbrella term; “Legionella pneumonia” is a common descriptive synonym (pqac-00000006, pqac-00000007) |
| Clinical definition | Severe pneumonia following inhalation of contaminated aerosols from engineered water systems | Reviews emphasize transmission from cooling towers, plumbing, showers, fountains, and similar systems rather than person-to-person spread (pqac-00000003, pqac-00000008) |
| Distinguishing related syndrome | Pontiac fever | Mild, non-pneumonic flu-like illness caused by *Legionella* exposure (pqac-00000006, pqac-00000022) |
| Typical transmission context | Inhalation/aspiration of aerosolized contaminated water | Built-environment and water-system exposures are the dominant source (pqac-00000003, pqac-00000007, pqac-00000028) |
| Key microbiologic classification | Gram-negative, aerobic/facultative intracellular bacterium | *L. pneumophila* is described as a Gram-negative intracellular pathogen that replicates in alveolar macrophages (pqac-00000002, pqac-00000034) |
| Primary host cell target | Alveolar macrophages | Central to disease mechanism and intracellular replication (pqac-00000009, pqac-00000013) |
| Main data source type for this entry | Aggregated disease-level resources and literature reviews, supplemented by database identifier mapping | Evidence synthesized from reviews, epidemiologic studies, and OpenTargets disease mapping rather than individual EHR-level data (pqac-00000000, pqac-00000005, pqac-00000007) |


*Table: This table summarizes core identifiers, classification terms, synonyms, and causative-agent information for Legionnaires' disease. It is useful as a compact reference for knowledge-base normalization and ontology mapping.*