Officials in French Polynesia on Tuesday declared an epidemic of chikungunya, a viral infection transmitted by mosquitoes. That day alone, 59 cases were reported on the island of Tahiti, and a further 200 suspected. Three patients are currently undergoing treatment in a hospital in Papeete, the island's capital. While the virus has a low fatality rate of 1 in 1,000 cases, the infection can nonetheless result in long-term disability.
French Polynesia is composed of 118 islands and atolls, lies around 2,500 miles south of Hawaii, and has a total population of 270,000.
Following the declaration, cases were also reported on the neighboring Tuamotu Archipelago and in the Austral Islands, confirming the rapid spread of the virus. Chikungunya, which is found in South Asia and Africa, and has been reported in southern Europe and the Caribbean in the last few years, had not yet cropped up in this part of the world.
Marc Lévy, a biologist at the Hospital of Papeete in Tahiti, explained the spread of the virus to VICE News: "The disease is not endemic; it landed in Polynesia. It's a new phenomenon for us… This is definitely the start of an outbreak. At first, there was a confusion between the symptoms of dengue fever [another mosquito-borne tropical disease] and those of chikungunya. In hindsight, we were able to identify several dozen cases of chikungunya."
The virus causes acute fever accompanied by severe muscle and joint pain, and there is currently no vaccine or medicine to prevent the disease.
Didier Raoult, a medicine professor at the University of Marseille and director of the Research Unit on Infectious and Emerging Tropical Diseases, told VICE News: "It is called an 'outbreak' if there are sufficient cases within a certain geographical zone, and a 'pandemic' when the disease affects several regions in the world. Today, chikungunya is set to become a pandemic."
French Polynesian authorities announced last Friday that they would be stepping up their control efforts and undertaking a campaign to eliminate the virus-carrying mosquitoes. Raoult told VICE News that the "tiger mosquito" is responsible for transmitting the disease, adding: "The mosquitoes are not carriers of the disease per se; they transmit it from one human to another. When a human is infected and a mosquito bites them, it then transmits the disease to the next person it bites. You need a contaminated human to spread this disease, therefore the virus migrates with humans. Chikungunya could be potentially be present in all the regions where these mosquitoes live."
According to Raoult, while the disease has a low mortality rate, the severeness of symptoms is nonetheless concerning: "You have to watch out in particular for those who associate illness with taking aspirin, for those who consume alcohol, and for the elderly. To deal with the symptoms, which are highly unpleasant, people are knocking back pain medication in a potentially lethal way."
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