Hantavirus
Usually linked to exposure to infected rodent urine, droppings, saliva, or contaminated dust. Some hantaviruses can cause severe lung or kidney-related illness.
Quick answer
Hantavirus is a group of rodent-borne viruses. Lassa fever is caused by Lassa virus and is endemic in parts of West Africa including Nigeria. Do not use either term to self-diagnose fever.
Lassa fever
Linked mainly to contact with food or household items contaminated by urine or faeces of infected multimammate rats. Person-to-person spread can occur, especially in healthcare settings.
Why the difference matters
Nigerians searching for hantavirus may really be worried about rat exposure, fever, or Lassa fever. The safe answer is not panic or self-diagnosis. It is to reduce rodent exposure and seek care for fever or serious symptoms.
Symptoms can overlap
Fever, weakness, muscle aches, vomiting, diarrhoea, and abdominal pain can appear in several infections. Lassa fever can be difficult to distinguish from malaria, typhoid, and other febrile illnesses early on.
Related: Lassa fever explained, Lassa fever vs malaria, Hantavirus explained.