Virus
Lassa virus
Arenavirus, Mastomys rat, West Africa
LAH-suh VY-rus
High-yield clue
Arenavirus of West Africa spread by Mastomys rat excreta; a classic sequela is sensorineural hearing loss.
Overview
An enveloped ambisense single-stranded RNA arenavirus (genus Mammarenavirus) with a segmented genome, studied as the West African hemorrhagic-fever virus carried by the multimammate rat.
Classification
- Arenaviridae
- Genus Mammarenavirus
- Ambisense ssRNA
- Two segments (bisegmented)
- Enveloped
Lab & identification clues
- Segmented ambisense arenavirus genome vocabulary
- 'Sandy' arenavirus (ribosome inclusion) framing
- Sensorineural hearing loss sequela association
Associations
- Mastomys natalensis (multimammate rat) reservoir
- Exposure to rodent urine/droppings
- West African endemic epidemiology
- Viral hemorrhagic fever presentation vocabulary
Commonly confused with
- Lymphocytic choriomeningitis virus
- Ebola virus
Frequently asked questions
What is Lassa virus?
An enveloped ambisense single-stranded RNA arenavirus (genus Mammarenavirus) with a segmented genome, studied as the West African hemorrhagic-fever virus carried by the multimammate rat.
What are the lab clues for Lassa virus?
Lab clues for Lassa virus include Segmented ambisense arenavirus genome vocabulary, 'Sandy' arenavirus (ribosome inclusion) framing, and Sensorineural hearing loss sequela association.
What is Lassa virus commonly confused with?
Lassa virus is commonly confused with Lymphocytic choriomeningitis virus and Ebola virus.
Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.