Peru on Monday reported its first cases of the chikungunya virus, in two people who recently traveled to the Dominican Republic, authorities said.

Health ministry director Henry Rebaza said the man and woman who were diagnosed in Lima had recently traveled to the Dominican Republic, a popular Caribbean vacation spot where the virus has been detected.

Rebaza said the couple have been isolated and so far are the only ones known to have been infected, and then diagnosed in Peru.

The virus—rarely fatal, but nevertheless serious—sparks high fevers and severe joint aches, as well as headaches, nausea and extreme fatigue.

It has spread across the Caribbean, to Central America and now South America.

In the Caribbean, 16 countries have seen cases since the beginning of June, according to Cuba's state-run newspaper Granma, and the World Health Organization counts 4,500 confirmed cases since the virus first appeared in December 2013.

The is carried by mosquitoes—most commonly the Aedes aegypti and Aedes albopictus, which are also responsible for dengue fever.

There is no vaccine or treatment for chikungunya, which has infected millions of people in Africa and Asia since the disease was first recorded in 1952.