Chikungunya is spread by two mosquito species, and is typically not fatal. But it can cause debilitating symptoms including fever, headache and severe joint pain lasting months.
The government of Chiapas, which borders Guatemala, said an 8 year old girl became the first person to contract the disease in Mexico, and that she was treated in hospital in the town of Arriaga. The girl has since been released.
There is no commercial vaccine for the virus, which was detected for the first time in the Americas late last year.
Chikungunya has already appeared in much of the Caribbean, Central America . . .