Not that many people have heard of Chikungunya, but that may change as the highly infectious disease keeps spreading quickly through the western hemisphere. The mosquito-borne virus, which causes fever and severe joint pain, may already be in Puerto Rico, and public health officials believe it could spread to the southern US within months, Al Jazeera finds. The first case in the Americas was detected on the Caribbean island of St. Martin in December and there have now been more than 25,000 cases reported in the region.
The disease—whose name means "that which bends up" in Tanzania's Makonde language—is painful but rarely fatal, and symptoms tend to clear up within a week or two, though some of those infected suffer recurring joint pain long after infection and there is no vaccine or treatment. Health officials say the outbreak is a "constantly evolving situation" as travelers continue to spread the virus, Global News reports. "We knew that it would spread once it got into the region," a CDC official says. “Because humans are really the main way that this is spreading." (More mosquito-borne woes: Malaria is reaching new heights.)