Health officials are monitoring a potential increase in chikungunya cases across multiple continents, with recent reports indicating a resurgence of the mosquito-borne virus in areas previously considered low-risk. The World Health Organization (WHO) is currently reviewing trial data for two recently approved chikungunya vaccines, though widespread availability remains limited.
Chikungunya virus disease is transmitted to humans through the bite of infected Aedes mosquitoes – specifically Aedes aegypti and Aedes albopictus – which are active during daylight hours, particularly around dawn and dusk. The virus, an RNA virus belonging to the alphavirus genus, was first identified in Tanzania in 1952 and has since spread to regions in Africa, Asia, the Americas, and Europe.
The disease presents with symptoms similar to dengue and Zika, often making accurate diagnosis challenging. Initial symptoms typically appear four to eight days after an infected mosquito bite and include fever and severe joint pain, which gives the disease its name – derived from a word in the Kimakonde language meaning “that which bends up,” referencing the contorted posture of those suffering from the joint pain. Additional symptoms can include headache, muscle pain, joint swelling, nausea, fatigue, and a rash.
While most individuals experience symptoms for less than a week, the joint pain can persist for months, or even years, in some cases. Severe illness and fatalities are rare, generally occurring in infants or elderly individuals with pre-existing health conditions. The Centers for Disease Control and Prevention (CDC) notes that the risk of transmission from an infected person to a mosquito is highest during the first week of illness, when viral loads in the blood are highest.
Currently, there is no specific antiviral treatment for chikungunya virus infections. Medical care focuses on alleviating symptoms with antipyretic and analgesic medications, such as paracetamol, to manage fever and pain. The CDC reports that the virus can, in rare cases, be transmitted from a pregnant woman to her fetus, particularly during the second trimester or at the time of delivery, potentially resulting in severe disease in the infant. Chikungunya virus has not been detected in breast milk, and transmission through breastfeeding has not been reported.
Beyond mosquito bites, transmission can occur through blood transfusions or via laboratory exposure to infected blood. The virus is not spread through coughing, sneezing, or casual contact. Public health officials emphasize preventative measures, including mosquito control and vaccination when recommended, particularly for travelers to endemic areas. The WHO continues to assess the global epidemiology of chikungunya to inform potential recommendations for vaccine use.
