China is facing a growing outbreak of chikungunya, a mosquito-borne illness, with thousands of cases now reported in the southern part of the country.

As of Friday, chikungunya cases had surged to 4,014, marking a sharp increase since local authorities in Foshan, Guangdong province, began tracking the virus two weeks ago, according to health department data. Foshan has been particularly hard-hit by the outbreak.

Sun Yang, deputy director of the National Center for Disease Control and Prevention, described the situation as “quite severe” during a press briefing in Foshan on Wednesday.

Chikungunya is transmitted through mosquito bites and typically causes fever and intense joint pain. While the symptoms can be debilitating, fatalities are rare, according to the World Health Organization (WHO).

China’s CDC has issued several health advisories on preventing both chikungunya and dengue — another mosquito-borne disease — urging people to use mosquito nets, repellents, and install physical barriers like screen doors. Authorities stated the current outbreak was "imported" but did not clarify from which country.

People showing symptoms such as fever, rashes, or joint pain are advised to seek medical attention.

The majority of infections — about 90% — have been reported in Shunde district, a popular tourist destination known for its Cantonese cuisine.

Images broadcast by state-run CCTV showed chikungunya patients lying in hospital beds protected by mosquito nets. To accommodate the growing number of patients, local authorities have increased mosquito-proof isolation beds to 7,220, according to local media.

Health officials in Guangdong are encouraging residents to eliminate standing water around their homes — commonly found in containers like flowerpots or kitchen appliances — to prevent mosquito breeding. Foshan’s Health Commission warned that violators could face fines of up to 10,000 yuan (approximately $1,400).

Beijing’s CDC reported that the capital occasionally sees imported cases of chikungunya.

Though two chikungunya vaccines have received regulatory approval in some countries, they are not yet widely used or broadly available, according to the WHO.

China’s first chikungunya outbreak occurred in 2010, with 253 cases reported in Dongguan, another city in Guangdong province. Prior to that, the first imported case was recorded in 1987, and while sporadic cases have appeared over the years, they were never widespread — until now.