Lassa

Lassa fever is an acute viral hemorrhagic illness caused by the Lassa virus. It is endemic in parts of West Africa including Sierra Leone, Liberia, Guinea, and Nigeria. The disease was first described in 1969 in the town of Lassa, in Borno State, Nigeria, after which it is named.

Transmission

Lassa fever is primarily transmitted to humans through contact with food or household items contaminated with the urine or feces of infected Mastomys rats. Human-to-human transmission can also occur, particularly in healthcare settings, through direct contact with the blood, tissue, secretions, or excretions of an infected individual.

Symptoms

The symptoms of Lassa fever typically appear 1-3 weeks after exposure to the virus. They can range from mild to severe and include:

• Fever
• General weakness and malaise
• Headache
• Sore throat
• Muscle pain
• Chest pain
• Nausea, vomiting, and diarrhea
• Cough
• Abdominal pain

In severe cases, the disease can cause bleeding from the gums, eyes, or nose, as well as respiratory distress, shock, and multi-organ failure.

Diagnosis

Diagnosis of Lassa fever is based on clinical symptoms and can be confirmed by laboratory testing, including enzyme-linked immunosorbent assay (ELISA), reverse transcription polymerase chain reaction (RT-PCR), and virus isolation techniques.

Treatment

There is no specific antiviral treatment for Lassa fever. However, the antiviral drug ribavirin has been shown to be effective if administered early in the course of the illness. Supportive care, including rehydration and treatment of specific symptoms, is also crucial.

Prevention

Preventive measures include:

• Promoting good "community hygiene" to discourage rodents from entering homes.
• Storing food in rodent-proof containers.
• Disposing of garbage far from the home.
• Maintaining clean households.
• Using protective equipment in healthcare settings to prevent nosocomial transmission.

Epidemiology

Lassa fever is endemic in parts of West Africa, with an estimated 100,000 to 300,000 infections and approximately 5,000 deaths annually. The disease poses a significant public health challenge in the region.

See also

• Hemorrhagic fever
• Ribavirin
• Mastomys rat
• West Africa
• Viral hemorrhagic fever

Related pages

• Ebola virus disease
• Marburg virus
• Dengue fever
• Yellow fever
• Zika virus