Funny, I was just reading a research article and accompanying review on Chikungunya just an hour ago.
Chik is very seldom lethal, but it causes a great deal of morbidity (illness, pain, lost productivity). And in the Indian Ocean epidemic that started in 2004 (and has affected your country), there have been runs of thousands of cases in some of the Indian Ocean islands like Reunion, Mauritius, and Seychelles. It's an extraordinarily painful illness, kind of like dengue, and people can have lingering pain long after the illness has subsided.
The editorial I just read (in the current issue of Journal of Infectious Diseases) mentions that the strain of Chik virus circulating in the Indian Ocean is genetically different than the ones elsewhere in the world, and it's now associated with a new mosquito vector, Aedes albopictus
. This mosquito is a VERY aggresive one that has spread all around the world via an illegal trade in used tires. It's in the USA now, though it has not been associated with any diseases.
So this is an interesting development. The traditional, better known mosquito vector for Chik has been Aedes aegypti
, which is the one that is best known for dengue and yellow fever.
You raise an interesting point about mortality. A lot of people have asserted that too much attention is paid to diseases that are lethal
compared to ones that are seldom lethal but cause great suffering and illness. Many major tropical diseases, like intestinal parasitoses, leprosy, leishmaniasis, etc, etc, are not lethal but cause great loss of productivity and make people susceptible to death from other causes.