Why in News?  

In Nigeria, the death toll from the Lassa fever outbreak in Africa’s most populous country has reached 138 since the beginning of this year.  

What is Lassa Fever?  

About the Disease  

• Lassa Fever is caused by a virus discovered in 1969 in Lassa, Nigeria.  
• It is endemic in West African countries like Sierra Leone, Liberia, Guinea, and Nigeria.  
• The virus is spread mainly by Mastomys rats (also called multimammate rats).  
• The overall death rate is around 1%, but it is higher for pregnant women, especially in the third trimester.  
• Around 80% of infections are asymptomatic, meaning most people do not show symptoms and remain undiagnosed.  

  Mode of Transmission  

• The disease is zoonotic – it spreads from rats to humans through food or household items contaminated with rat urine or feces.  
• Human-to-human transmission is rare but possible through infected bodily fluids or contact with eyes, nose, or mouth.  

Treatment: Ribavirin, an antiviral drug, is considered effective if given early during the illness.