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transmission

How is Lassa fever transmitted?

The primary route is contact with the multimammate rat (Mastomys natalensis) — specifically its urine, faeces, or saliva — or by handling and consuming infected rats. Human-to-human transmission occurs through direct contact with blood, urine, faeces, vomit, or other bodily fluids of an infected person. Lassa fever is NOT airborne; casual contact poses minimal risk. Healthcare workers are at risk without adequate PPE. Sexual transmission is documented during convalescence, as the virus persists in semen for up to three months.

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Last update Jun 9, 2026 · ⚠ Not medical advice. Information is provided for awareness only; consult a physician for individual health questions.