Aedes albopictusCDC, JAMES GATHANYSince its discovery in Africa in the 1950s, chikungunya virus has traveled around the Indian Ocean region, infecting tens of millions of people. Those affected suffer high fevers, rashes, and intensely painful arthritis that lasts for weeks.
Now, chikungunya virus has arrived in the Western hemisphere, with locally transmitted infections recorded since December 2013 on the Caribbean island of St. Martin. Within six short months, more than 100,000 suspected infections have been found in 17 countries of the Caribbean and South America, according to the US Centers for Disease Control and Prevention (CDC).
Originally, yellow fever mosquitoes (Aedes aegypti) transmitted this RNA virus to people. In 2006, however, chikungunya virus linked up with Asian tiger mosquitoes (Aedes albopictus) on the tiny island of La Réunion, east of Madagascar. The encounter selected for viruses with a single change in the E1 envelope glycoprotein, from an alanine to a valine at position 226 (A226V). That simple change enabled A. albopictus to be an efficient ...