Chikungunya

Chikungunya is a viral disease transmitted to humans by infected female Aedes mosquitoes, caused by the chikungunya virus (CHIKV), an RNA virus of the alphavirus genus in the family Togaviridae ^[1][2][3]. The name derives from a Kimakonde term meaning 'that which bends up,' describing the stooped posture of those with severe joint pain ^[2][3].

The disease typically begins abruptly with fever and severe joint pain, frequently accompanied by muscle pain, headache, rash, nausea, and fatigue ^[1][2][3]. Symptoms usually appear 4–8 days after a mosquito bite and are generally self-limiting over days to weeks, though joint pain may persist for months in some cases ^[1][3]. Severe presentations, including neurological complications and rare deaths, have been reported in a minority of infections ^[5].

CHIKV was first identified in Tanzania in 1952 and later spread through Africa and Asia, with urban outbreaks recorded from the 1960s–1970s ^[2][3]. Since 2004, outbreaks have grown more frequent and widespread, and the virus has now been reported in over 110 countries across Asia, Africa, the Americas, and Europe ^[2][3]. In the past 15 years, major epidemics have affected the Indian Ocean, Caribbean, and Americas, with viral adaptation to Aedes albopictus enabling expansion into temperate zones ^[4].

The virus is transmitted to people by the bite of infected female Aedes aegypti and Aedes albopictus mosquitoes, which feed mainly during daylight hours and lay eggs in standing water ^[1][2][3]. An uninfected mosquito becomes infected after feeding on a person with circulating virus, then can transmit to others; patients in the first week of illness can infect mosquitoes through bites ^[2]. Genetic adaptation to Aedes albopictus raises the potential for further geographic spread ^[4].

Avoiding mosquito bites is the primary protection, and suspected cases should prevent bites during the first week of illness to limit mosquito infection ^[1][2]. Community mobilization to remove water-holding containers, dispose of waste, and support vector-control programmes reduces breeding sites ^[2]. Insecticide spraying may be used during outbreaks, and approved vaccines exist but are not yet widely available ^[2].

1. 1 World Health Organization. Chikungunya [Internet]. cited 3 Sept 2026. Available from: https://www.who.int/news-room/questions-and-answers/item/chikungunya
2. 2 World Health Organization. Chikungunya fact sheet [Internet]. cited 3 Sept 2026. Available from: https://www.who.int/news-room/fact-sheets/detail/chikungunya
3. 3 World Health Organization. Chikungunya [Internet]. cited 3 Sept 2026. Available from: https://www.who.int/health-topics/chikungunya
4. 4 Burt FJ et al. Chikungunya virus: an update on the biology and pathogenesis of this emerging pathogen. Lancet Infect Dis. 2017 Apr. PMID: 28159534. doi: 10.1016/S1473-3099(16)30385-1. PubMed: https://pubmed.ncbi.nlm.nih.gov/28159534/
5. 5 de Lima Cavalcanti TYV et al. A Review on Chikungunya Virus Epidemiology, Pathogenesis and Current Vaccine Development. Viruses. 2022 May 5. PMID: 35632709. doi: 10.3390/v14050969. PubMed: https://pubmed.ncbi.nlm.nih.gov/35632709/