Symptoms
Chikungunya manifests itself after an incubation period of 1-12 days in high fever, chills, headache, sensitivity to light, rash, and severe muscle and joint pain. The duration of illness is 1-2 weeks. Serious complications and a fatal outcome are rarely possible. Pain in various joints characterizes the disease and may persist for months to years after the acute disease has healed. The fingers, wrists, elbows, toes and knees are often affected and the pain is also accompanied by swelling. Chronic fatigue may also occur as a result of the disease. Large outbreaks have been observed in affected areas in recent years. In many countries, the disease occurs in people returning from travel. The African name “chikungunya” refers to the twisted posture that patients assume because of the pain.
Causes
The cause of the disease is infection with chikungunya virus (CHIKV), an enveloped alpha and RNA virus of the togavirus family found in tropical and subtropical regions of Africa, India, Indian Ocean islands, and South and Southeast Asia. The virus was first isolated from the blood of a fever patient in Tanzania in 1953.
Transmission
The virus is transmitted by infected mosquitoes of the genus including the yellow fever mosquito , which is also a vector for yellow fever and dengue, and , the Asian tiger mosquito. In Africa, the virus circulates between primates, small mammals and the mosquitoes. During a local outbreak, the virus can also be transmitted exclusively between humans. In Asia, it circulates primarily between humans.
Diagnosis
Diagnosis is made on the basis of clinical symptoms, patient history, epidemiologic situation, and laboratory methods. Because of the similar symptoms and transmission, chikungunya is probably often confused with dengue. Malaria must also be excluded from the diagnosis.
Prevention
A vaccine is not currently available. Therefore, it is important to avoid the insect bites with various measures. Caution: -Mosquitoes bite in contrast to also during the day. Recommended measures include:
- Appropriate clothing
- Repellents, e.g. DEET, insecticides.
- Rules of conduct
Treatment
Chikungunya is treated symptomatically with non-steroidal anti-inflammatory drugs such as ibuprofen and naproxen, glucocorticoids and other analgesics such as paracetamol. Adequate hydration and bed rest are also prescribed. Light physical exercise may have a positive effect. Causal treatment with antiviral drugs has been insufficiently studied. The use of chloroquine in the chronic phase is discussed.
