Have you ever heard about Lassa fever? A rat common in West Africa is responsible for Lassa fever which is an acute and a viral disease. The Lassa fever can be life-threatening as it takes a toll on your liver and kidneys. You may contract it due to the urine and faeces of Multimammate rat (Mastomys natalensis). The Lassa fever is commonly seen amongst people of Sierra Leone Liberia Guinea and Nigeria. The name Lassa comes from the name of the village in Nigeria where the fever was documented first. The viral infection was carried out by Mastomys natalensis (M. natalensis).