Lassa fever has killed more than 160 people in West Africa, most of them in Nigeria, since November 2015. Many of these lives could have been saved if a rapid diagnostic test were available so that people could receive treatment early.

Nigeria/Alvaro1984 18
Nigeria/Alvaro1984 18

Since November 2015, Nigeria, Benin, Sierra Leone and Togo have reported more than 300 cases of Lassa fever and 164 deaths. Nigeria accounts for the majority of the cases with 266 cases and 138 deaths reported in 22 of the country’s 34 provinces. Benin has recorded 51 cases and 25 deaths, Togo and Sierra Leone each reported 2 cases.

This has prompted the World Health Organization (WHO) to call for early diagnostic tests for the viral disease. “Without early diagnosis and treatment, 1 in 5 infections result in severe disease, where the virus affects several organs such as the liver, spleen and kidneys,” explains Dr Formenty, expert in hemorrhagic fevers at WHO.

“We need resources to invest in diagnostics to easily, accurately and safely test for Lassa fever as we do for malaria and HIV. Without a proper diagnosis, many people do not receive the correct treatment and that is why we see so many people with Lassa fever dying each year.”

Lassa virus is carried by the Mastomys rat, which is found in parts of West Africa. The virus is transmitted to humans from direct contact with infected rats by catching and preparing them for food, or through contact with food or household items contaminated with rat feces or urine. The virus can also be transmitted through contact with an infected person’s body fluids.

Around 80% of people who become infected with Lassa virus have no symptoms or they have symptoms that mimic other illnesses, such as malaria, making it difficult to treat them. Symptoms include fever, fatigue, nausea, vomiting, diarrhea, headaches, abdominal pains, sore throat and facial swelling.

Ribavirin has been used successfully in the treatment of confirmed Lassa cases. This drug can treat infected people if it is administered as soon as the first signs appear.