United States health officials are urging travellers to remain vigilant as a mosquito-borne virus continues to circulate across parts of Asia, Africa, Europe, Latin America and the Indian Ocean.Since the beginning of 2025, there have been approximately 240,000 chikungunya virus infections and 90 deaths in 16 countries, according to the European Centre for Disease Prevention and Control (ECDC).In China, an outbreak has infected roughly 7,000 people since late June, with most cases concentrated in the city of Foshan, in Guangdong province, just north of Hong Kong. This marks the country's largest chikungunya outbreak since the virus was first identified there in 2008.Here is what we know about the disease and how it is spreading.What is the chikungunya virus?Chikungunya is a viral disease that is spread through the bite of infected Aedes aegypti mosquitoes. These mosquitoes also carry and spread dengue, yellow fever and the Zika virus.The name, chikungunya, derives from a word in the Kimakonde language, spoken in Tanzania and Mozambique, meaning "to become contorted".In most cases, patients will feel better within a week. In many cases, however, the joint pain can last for months or even years.There is no cure for the chikungunya virus, but deaths are rare. If an infected mosquito bites a healthy human, it injects the virus into the bloodstream.People most at risk of serious illness from chikungunya include newborns, older adults and those with existing health problems such as heart disease or diabetes. Advertisement There is no cure for the chikungunya virus, but the death rate is low, except in high-risk populations.If an infected mosquito bites a healthy human, it injects the virus into the bloodstream. If a non-infected mosquito bites a person who is already infected, it sucks the virus from that ...