First discovered in Nigeria, the symptoms of this disease can seem similar to Ebola
Name
Lassa fever
Transmission
- An infectious haemorrhagic virus which lives in the Mastomys or multimammate rat
- People become infected mostly through direct contact with infected rats or through food or household items contaminated with infected rodent feces/urine
- Person-to-person transmission via exposure to blood, tissue, urine, or feces of an infected individual is also possible
Geography
- Endemic in the rodent population across parts of West Africa
- The virus was discovered in Lassa, Borno State, Nigeria in 1969
Incubation Period
2 – 21 days after infection
Signs and Symptoms
Phase One (mild symptoms):
- Fever
- Weakness
- Headache
- Sore throat
- Vomiting
- Muscle pain
- Chest Pain
- Nausea
- Cough
- Diarrhea
Phase Two (severe symptoms):
- Hemorrhaging
- Respiratory distress
- Facial swelling
- Shock
- Hearing loss
- Tremors
- Encephalitis
- Seizures
- Coma
About 80% of infected people have no symptoms
Diagnosis
- Laboratory testing of blood samples
- Because early symptoms are varied and non-specific, clinical diagnosis is often difficult
- Lassa fever is difficult to distinguish from Ebola, malaria, typhoid fever, and yellow fever among others
Treatment
- Antiviral drugs (e.g. Ribavirin) and supportive care (fluid/electrolyte balance, oxygenation, etc.) are the best forms of treatment
Prognosis
- Fatality rates range from 1% to 15% depending on the severity of the infection, but during epidemics, mortality can climb as high as 50%
- Death usually occurs within 14 days
- Deafness occurs in 25% of patients who survive and 50% of those who become deaf will partially regain their hearing in 1–3 months
Prevention: What Can You Do?
- Avoid contact with rodents
- Seal and store food in rodent-proof containers
- Dispose of garbage far from your home
- Keep your home clean and exterminate if you have a rodent problem
Lassa Fever In the News
- DRASA Partner’s Lassa Fever Research Breakthroughs
- Lassa fever death rates in Nigeria higher than expected
Sources:
https://www.cdc.gov/vhf/lassa/index.html
http://www.who.int/mediacentre/factsheets/fs179/en/
