A 24-year-old-woman with a suspected case of West Nile fever, a relatively unknown viral infection in this part of the region, has been admitted to the Kozhikode medical college hospital.
Health Department officials said that the patient had been under treatment since July 13 for fever whose symptoms resembled Japanese Encephalitis. She had been shifted to an isolation ward.
Various samples including serum of the patient were sent to the National Institute of Virology (NIV) in Pune to confirm the West Nile fever, typically spread by Monsonia and Qulex mosquitoes. However, the viral infection can be confirmed only if the second samples sent to the laboratory tested positive. These would be sent from the medical college on Saturday, V. Jayasree, District Medical Officer, said in a statement here on Friday, adding that the confirmation on the disease would be further delayed.
Meanwhile, unconfirmed reports said that another person with similar symptoms was also admitted to the medical college hospital.
Studies on the West Nile fever in Kerala has been going on for quite sometime since the outbreak of the viral infection in the coastal areas of Alappuzha more than a decade ago. The prevalence of the virus was raised in Alappuzha and parts of Kottayam in 2006 during the outbreak of Chikungunya. West Nile fever was first noticed in India in 1956 and a study published by the NIV in 1973 had mentioned the presence in Kerala.
The World health Organisation (WHO) on its website says that the transmission of West Nile Virus to humans is most often the result of bites from infected mosquitoes. Mosquitoes become infected when they feed on infected birds, which circulate the virus in their blood for a few days.
Infection with West Nile virus is either asymptomatic (no symptoms) in around 80% of infected people, or can lead to West Nile fever or severe West Nile disease. About 20% of people who become infected with West Nile virus will develop West Nile fever. Symptoms include fever, headache, tiredness, and body aches, nausea, vomiting, occasionally with a skin rash (on the trunk of the body) and swollen lymph glands.
Treatment is supportive for patients with neuro-invasive West Nile virus, often involving hospitalization, intravenous fluids, respiratory support, and prevention of secondary infections. No vaccine is available for humans.