Chikungunya fever is an emerging viral disease characterized by high fever and severe joint pain. The name "Chikungunya" is derived from the Makonde word meaning "that which bends up," referring to the stooped posture of those suffering from joint pain. The disease is transmitted through mosquito bites and has seen outbreaks in various regions, including India, Africa, and Southeast Asia.
⚠️ How is Chikungunya Transmitted?
Chikungunya virus (CHIKV) is an arbovirus (arthropod-borne virus) belonging to the Alphavirus genus. It spreads mainly through the bite of infected mosquitoes, specifically:
π¦ Aedes aegypti – Primarily found in urban areas
π¦ Aedes albopictus – Common in rural and forested areas
Other Modes of Transmission:
✔ Mother-to-child transmission – If the mother is infected at the time of delivery
✔ Blood transfusion and organ transplantation – Extremely rare but possible
π©Ί Symptoms of Chikungunya
The incubation period (time from infection to symptoms) is 3 to 7 days. Symptoms typically last for 7 to 10 days, but joint pain may persist for weeks or months.
Common Symptoms:
✅ High fever (lasting 5–7 days)
✅ Severe joint pain (polyarthritis/polyarthralgia) – Mostly in wrists, ankles, and small joints
✅ Skin rash – Appears on the 2nd to 4th day of illness
✅ Headache and fatigue
✅ Muscle pain (myalgia)
✅ Retro-orbital pain (pain behind the eyes)
✅ Mild bleeding symptoms (nosebleeds, gum bleeding)
How is it Different from Dengue?
Unlike dengue, Chikungunya does not cause severe complications like hemorrhagic fever or organ failure. However, prolonged joint pain can significantly impact daily activities.
π§ͺ Diagnosis of Chikungunya
Doctors diagnose Chikungunya based on clinical symptoms and laboratory tests, such as:
1) Viral isolation in mosquito cell lines (takes 1-2 weeks) is useful for early diagnosis (0-7 days).
2) Serum antibody detection -
❖ Igm appears after 4 days of infection and lasts for 3 months ; IgG appears late ( after 2 weeks) and lasts for years. So, detection of IgM or a fourfold rise in IgG titler is more significant
❖ MAC (IgM antibody capture) ELISA ( using virus lysate) is the best format available showing excellent sensitivity (95%) and specificity (98%) with only little cross reactivity with other alphavirus and dengue.
3) Molecular Method - Reverse transcriptase PCR has been developed to detect specific gene (e.g. nsP1 , nsP4 ) in blood.
4) Biological markers like IL-1Ξ² and Il-6 are increased and RANTES (Regulated on activation, normal T cell expressed and secreted) levels are decreased in chikungunya virus infection.
5) Hemotological findings - Such as leuokopoenia with lymphocyte predominance, thrombocytopenia (rare), elevated ESR and C-reactive protein.
π Treatment & Management
There is no specific antiviral drug for Chikungunya. The treatment focuses on symptom relief through:
π Pain relievers (Paracetamol, NSAIDs) – For fever and joint pain
π₯€ Hydration – Prevents dehydration
π Rest and supportive care – Helps in faster recovery
⚠ Avoid Aspirin & Ibuprofen in case of co-infection with dengue, as they increase the risk of bleeding.
Genotypes
Chikungunya virus has three genotypes-
(1) West African
(2) East African
(3) Asian genotypes
(4) Indian Ocean Lineage (IOL).
❖ Most Indian cases before 1973 were due to Asian
❖ However, Reunion outbreak was caused due to a mutated strain which was closely related to an African genotype from Kenya and is responsible for most of the current outbreaks in India as well as in other parts of the world
❖ The genotypes distribution is due to differences in their transmission cycles; for example, human cycle in Asia and forest cycle in Africa.
π‘️ Prevention of Chikungunya
Since there is no vaccine for Chikungunya, prevention relies on mosquito control.
✔ Preventive Measures:
π¦ Eliminate mosquito breeding sites – Avoid stagnant water in containers, tires, and plant trays
π¦ Use mosquito repellents – DEET-based or natural repellents (like citronella oil)
π¦ Wear protective clothing – Long sleeves and pants reduce bites
π¦ Use insecticide-treated bed nets and window screens
π Community Measures:
π’ Government initiatives – Public health campaigns and mosquito control programs
π’ Awareness programs – Educate communities about symptoms and prevention
π Chikungunya in India and Recent Outbreaks
❖ Chikungunya has been reported in Africa, Asia, and the Americas.
❖ In India, outbreaks have been recorded in Maharashtra, West Bengal, and Tamil Nadu.
π
First outbreak in India: 1963
π
Major outbreaks: 2006 and 2016
❖ India (past): Several outbreaks were reported during 1963-1973; e.g. Kolkata in 1963 and South India in 1964 (Puducherry, Chennai-Vellore region) and Barsi in Maharashtra in 1973
❖Since then, it was clinically quiescent and no outbreaks were reported between 1973-2005 from most parts of the world, except for the few sporadic cases, which occurred in various places in the world including India (Maharashtra)
❖ Re-emergence (Reunion Outbreak): In 2005, Chikungunya re-emerged in Reunion Island of Indian Ocean and affected 2.58,000 people (almost one-third of country's population)
❖ Reasons for Re-emergence
:
✔ Re-emergence in 2005 was believed to be due to a novel
mutation in the virus and a change in vector.
✔ New mutation (E1-A226V): Chikungunya virus underwent an important mutation.
✔ Alanine in the 226
position of E1 glycoprotein gene is replaced by valine New vector (Aedes albopictus). This mutation led to a shift of vector preference.
✔ Mutated virus was found to be 100 times more infective to A. albopictus than to A aegypti
π Read more on WHO’s official website: Chikungunya – WHO
π♂️ Frequently Asked Questions (FAQs)
1. Is Chikungunya deadly?
❌ No, Chikungunya is rarely fatal. However, it can cause chronic joint pain lasting for months.
2. Can Chikungunya spread from person to person?
❌ No, the virus is only transmitted through mosquito bites.
3. Is there a vaccine for Chikungunya?
❌ No, but research is ongoing.
4. How long does Chikungunya last?
⏳ Most people recover within 7–10 days, but joint pain can persist for months.
5. Can Chikungunya occur more than once?
π No, once infected, you develop lifelong immunity.
π Sources & Further Reading
π Conclusion
Chikungunya is a mosquito-borne viral disease that causes severe joint pain, skin rashes and fever. Though not fatal, it can lead to long-term arthritis-like symptoms. Since there is no specific treatment or vaccine, the best prevention is mosquito control and community awareness.
By staying informed and taking precautions, we can reduce the impact of Chikungunya and protect ourselves and our communities.
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