CHIKUNGUNYA

Chikungunya is an infection caused by the chikungunya virus (CHIKV). The disease was first identified in 1952 in Tanzania and named based on the Kimakonde words for “to become contorted”. Chikungunya has become a global health concern due to its rapid geographic expansion, recurrent outbreaks, the lack of effective antiviral treatments, and the potential to cause high morbidity. Chikungunya virus is closely related to O’nyong’nyong virus (ONNV), which shares similar genetic and clinical characteristics.
Symptoms include fever and joint pain. These typically occur two to twelve days after exposure. Other symptoms may include headache, muscle pain, joint swelling, and a rash.
Symptoms usually improve within a week; however, occasionally the joint pain may last for months or years. The risk of death is around 1 in 1,000. The very young, old, and those with other health problems are at risk of more severe disease.
The virus is spread between people by two species of mosquitoes in the Aedes genus: Aedes albopictus and Aedes aegypti, which mainly bite during the day, particularly around dawn and in the late afternoon. The virus may circulate within several animals, including birds and rodents. Diagnosis is done by testing the blood for either viral RNA or antibodies to the virus.^[6] The symptoms can be mistaken for those of dengue fever and Zika fever, which are spread by the same mosquitoes. It is believed that most people become immune after a single infection.
The best means of prevention are overall mosquito control and the avoidance of bites in areas where the disease is common. This may be partly achieved by decreasing mosquitoes’ access to water, as well as the use of insect repellent and mosquito nets. Chikungunya vaccines have been approved for use in the United States and in the European Union.
The Chikungunya virus is widespread in tropical and subtropical regions where warm climates and abundant populations of its mosquito vectors (A. aegypti and A. albopictus) facilitate its transmission. In 2014, more than a million suspected cases occurred globally While the disease is endemic in Africa and Asia, outbreaks have been reported in Europe and the Americas since the 2000s; 6 in 2014, an outbreak was reported in Florida in the continental United States. At the end of March, a severe outbreak of the Chikungunya virus (alongside dengue) was reported in Sri Lanka. As of the second week of March 2025, there are 173 documented cases. Additionally, there have been 340 hospital admissions and 12 deaths linked to Chikungunya in 2025. 7000 cases occurred in China. 
Signs and symptoms. Around 85% of people infected with the Chikungunya virus experience symptoms, typically beginning with a sudden high fever above 39 °C (102 °F). The fever is soon followed by severe muscle and joint pain. Pain usually affects multiple joints in the arms and legs, and is symmetric. People with Chikungunya also frequently experience headaches, back pain, nausea, and fatigue. Around half develop a rash, with reddening and sometimes small bumps on the palms, foot soles, torso, and face. Some people experience gastrointestinal issues, with abdominal pain and vomiting. Others experience eye – sensitivity to light, conjunctivitis, and pain behind the eye. This first set of symptoms – called the “acute phase” of chikungunya – lasts around a week, after which most symptoms resolve on their own.
Many people continue to have symptoms after the “acute phase” resolves, termed the “post-acute phase” for symptoms lasting three weeks to three months, and the “chronic stage” for symptoms lasting longer than three months. In both cases, the lasting symptoms tend to be joint pains: arthritis, tenosynovitis, and/or bursitis. If the affected person has pre-existing joint issues, these tend to worsen. Overuse of a joint can result in painful swelling, stiffness, nerve damage, and neuropathic pain. Typically, the joint pain improves with time; however, the chronic stage can last anywhere from a few months to several years.