Lassa Fever

The incubation period of the virus is between three and 21 days.

Early symptoms
When symptoms are present, fever and general weakness are generally the first reported. This is followed by headaches, muscle pain, chest pain, nausea, vomiting, diarrhoea and abdominal pain. 

Severe symptoms
Swelling of the face and bleeding from all body openings are severe signs of this disease. It is common for people infected with Lassa fever to become deaf following the onset of symptoms. This can develop in both mild and severe cases.

No vaccine is available to prevent Lassa fever, so avoidance of endemic areas is recommended. If you are in an affected area, storing your food in rodent-proof containers and keeping your area clean will help discourage rodents from entering your home. If you are around an infected person, you should wear protective clothing, such as masks, gloves, gowns, and goggles; use infection control measures and sterilise equipment; and isolate infected patients from contact with unprotected individuals until they have recovered.

Although the risk to international travellers is extremely low, the existence of this disease underscores the importance of seeking medical attention for any fever while travelling in high-risk areas. Antiviral treatments can be used in the early stages of the disease. Lassa fever is also treated through maintenance of fluids, oxygenation and blood pressure.