Report Confirmed or Suspect Cases Immediately to the Local Health Department.

Lassa fever is an infection caused by the Lassa virus (in the family of arenaviruses). Lassa fever is part of the group of diseases known as viral hemorrhagic fevers since in severe cases, it may lead to bleeding disorders. The majority of people infected with Lassa virus will have mild symptoms such as fever, fatigue and headache, but about 2 in 10 will develop a more serious infection with chest or abdominal pain, vomiting, or hemorrhaging and this can affect many if the body’s organ systems and lead to shock and in some cases death. About 1/3 of people with Lassa Fever will also experience some hearing loss. The Lassa virus is spread to people through contact with urine and droppings of multimammate rats found primarily in West Africa. People who are infected can then transmit the disease to other people through contact with infected body fluids of a symptomatic person. It is not spread through casual contact but can spread to caretakers and within healthcare settings if recommended infection control measures (including PPE) are not observed. An antiviral drug called Ribavirin has been used to treat people with Lassa fever, along with supportive care.  

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• Lassa Fever Training for Healthcare Providers

• Frequently Asked Questions