Chikungunya Fever

Chikungunya fever is a viral disease that is transmitted to humans through the bite of an infected mosquito.

The risk for travellers of acquiring chikungunya is greatest if they are visiting an area with an ongoing epidemic of the disease. Epidemics usually occur during the tropical rainy season and abate during the dry season.

Everyone is susceptible to chikungunya fever, but having the disease once is thought to result in life-long immunity to the virus.

Chikungunya fever is a serious illness, most often characterized by fever, headache, fatigue, nausea, vomiting, muscle pain, rash, and joint pain. Acute chikungunya fever generally lasts for a few days to a few weeks, however, some patients can have prolonged fatigue that may last for several weeks. Severe joint pain or arthritis, lasting for weeks or months, can also occur. Infections without presentation of any symptoms at all have also occurred.

Chikungunya fever is usually not fatal, although a few fatalities due to this virus have occurred. Complications are rare but serious and can include inflammation in the heart, ocular disease, hepatitis, and neurological symptoms, such as meningoencephalitis (inflammation of the brain and surrounding layers).

Recent findings show that after contracting the virus, the chance of developing encephalitis (brain inflammation) increases by alarming rates. Even if encephalitis was more likely to affect senior citizens and infants, an alarming number of cases have been shown to affect adults, with 8.6 people out of 100,000 developing the condition. The rate by which encephalitis occurs in infants is 187 per 100,000 cases, while for elderly citizens over 65, it was 37 per 100,000 cases.

There is no specific antiviral treatment currently available for chikungunya fever. Care for chikungunya fever patients involves supportive measures, such as rest, fluids, and medicines to relieve the symptoms of fever and aching. Infected persons should be protected from further mosquito exposure during the first few days of the illness to prevent any contribution to the transmission cycle by infecting more mosquitoes that can go on to transmit the disease to other people. 

This disease occurs in many tropical countries, including sub-Saharan African countries, Pakistan, India, southeast Asia, Malasia, and Indonesian and Philippine Islands. Recently (December, 2013), the infection was discovered for the first time in the western hemisphere in Saint Martin in the Caribbean. It is likely that it will spread to other areas where the right mosquito can become infected and spread the disease.