Chikungunya virus

Chikungunya virus

1. Chikungunya Also known as Chicken Guinea It is a mosquito borne viral disease caused by Chikungunya virus viral infection spread by the mosquitoes of genus Aedes 1. Aedes Aegypti , 2. Aedes Albopictus (Tiger mosquito ). Chikungunya comes from the word “ kungunyala ” in Makonde language which means “that which bends up” or “contoured” The person affected with Chikungunya walks with a stooped posture due to the joints pain

2. Aggressive daytime-biting mosquitoes highly-infective. It is possible for a person to have chikungunya and dengue fever together at the same time because the infected aedes mosquito can carry both the viruses.

3. What Happens in Chikungunya? Acute Phase Incubation period is usually 2 to 6 days Abrupt onset of fever with joint pains and stiffness, especially at beginning of motion Temperature is usually high, between 1020F and 1040F Rashes occur after onset of fever Fever subsides after a couple of days Other symptoms include headache, muscle pain , nausea, vomiting, fatigue, mouth ulcers, conjunctivitis , loss of taste, loss of appetite, etc . last for about 5 to 7 days . The severe muscle and joints pain makes movement difficult and prostates the person

4. Continue…. Chronic Phase Continued multiple joints pain that may persist from weeks to years 95% of adults remain symptomatic for weeks to months with loss of mobility , decreased fine movements of fingers, and slow reactions. Recurrent joints pain is seen in 30-40% victims Rarely , infections of heart muscle, brain coverings and bleeding have been recorded Death is rare and usually occurs in people over 65 or small children, especially those with other underlying

5. What causes chikungunya and how is it transmitted? Over viewIt is a mosquito borne viral disease caused by Chikungunya virus . The mosquitoes breed on stagnant water . The mosquitoes bite during daytime with peaks in early morning and late afternoon Mosquitoes acquire the virus from humans , and after a period of 8 to 10 days they transfer it to other humans while feeding The virus circulates in blood of infected person for several days at approximately the time when the person gets the fever

6. What are risk factors for chikungunya ? Damp marshy areas. Areas with stagnant or collected water Mosquito prone areas Attendants of Chikungunya patients Individuals with weak immune systems Infection from mother to newborn during delivery Rainy season Old people or small children with other underlying illnesses

7. What can chikungunya lead to? Most common complication is: Chronic Arthritis Rare and serious complications are: Heart affections Inflammation of eye Acute kidney disease Inflammation of coverings of the brain Stroke and Paralysis Severe large skin lesions Infection from Rarely , death

8. Human Immune Response Flavivirus cause acute sporadic disease and are not persistent. The outcome of flavivirus infection in an animal is determined by a balance between the speed of viral replication and spread, and the immune system response. Flaviviruses have evolved specific tactics to evade the innate and adaptive immune response.

9. Continue…. Flaviviruses , have genomic size constraints, and are unable to acquire exogenous genes. Smaller viruses evolve multifunctional genes that regulate viral life cycle, yet also modulate the host response. The infected cells migrate to draining lymph nodes where arise early immune response. Then reach secondary lymphoid tissues, leading to entry into the circulation via the efferent lymphatic system and thoracic duct.

10. Continue… Now spread to visceral organs , then to neurotropic flaviviruses disseminate to the central nervous system The mechanism by which flaviviruses avoid being targeted by its entry into brain and spinal cord remains unclear There is an assumption that the virus enters via a haematogenous route. Flaviviruses may cross the blood–brain barrier by passive transport across the endothelium, by active replication in endothelial cells. Trojan horse' mechanism in which the virus is carried into the brain by infected inflammatory cells The IFN-dependent innate immune response is essential for protection against flavivirus infections . Type I and II IFN inhibit flavivirus infection in cell culture and in animals.

11. Continue… Type I IFN block flavivirus infection by preventing translation and replication of infectious viral RNA. Type II IFN inhibit flavivirus replication via the generation of proinflammatory and antiviral molecules including nitric oxide .

12. DIAGNOSIS Can be confirmed by presence Zika virus RNA in the blood or other body fluids, such as urine or saliva Zika virus RNA has been detected in urine up to 10 days after onset of the disease. From day five post onset of disease, serological investigations can be conducted by detection of Zika -specific IgM antibodies and confirmation by neutralisation , seroconversion or four-fold antibody titer increase of Zika specific antibodies in paired serum samples.

13. AVAILABLE TREATMENT There is no vaccine or specific prophylactic treatment. Bharat biotech international company of India declared that they patented for medicine for ZIKV. The treatment is symptomatic and mainly based on pain relief, fever reduction and anti-histamines for pruritic rash.

14. PREVENTION The best form of prevention is protection against mosquito bites. Repellents should contain DEET (N, N-diethyl-3- methylbenzamide ), IR3535 (3-[N-acetyl-N-butyl ]- aminopropionic acid ethyl ester) or icaridin ( 1 piperidinecarboxylic acid, 2-(2-hydroxyethyl)- 1- methylpropylester ).