The Kerala health department is on alert after the death of a 47-year-old from Thrissur due to the West Nile Virus.
- Earlier in 2019, a six-year-old boy in Malappuram district had died of the same infection.
GS II- Health
Dimensions of the Article:
- About West Nile Virus
- Detection of WNV
About West Nile Virus
- The West Nile Virus is a mosquito-borne, single-stranded RNA virus.
- The virus was first reported in the state in Alappuzha in 2006 and then in Ernakulam in 2011.
- According to the WHO, it is “a member of the flavivirus genus and belongs to the Japanese Encephalitis antigenic complex of the family Flaviviridae”.
- Culex species of mosquitoes act as the principal vectors for transmission.
- It is transmitted by infected mosquitoes between and among humans and animals, including birds, which are the reservoir host of the virus.
- Mosquitoes become infected when they feed on infected birds, which circulate the virus in their blood for a few days.
- The virus eventually gets into the mosquito’s salivary glands.
- During later blood meals (when mosquitoes bite), the virus may be injected into humans and animals, where it can multiply and possibly cause illness.
- WNV can also spread through blood transfusion, from an infected mother to her child, or through exposure to the virus in laboratories.
- It is not known to spread by contact with infected humans or animals.
- According to the US Centre for Disease Control and Prevention (CDC), it does not spread “through eating infected animals, including birds”
- To date, no human-to-human transmission of WNV through casual contact has been documented.
- The disease is asymptomatic in 80% of the infected people.
- The rest develop what is called the West Nile fever or severe West Nile disease.
- In these 20% cases, the symptoms include fever, headache, fatigue, body aches, nausea, rash, and swollen glands.
- Severe infection can lead to encephalitis, meningitis, paralysis, and even death.
- It usually turns fatal in persons with co-morbidities and immuno-compromised persons (such as transplant patients).
Detection of WNV
- The virus was first isolated in a woman in the West Nile district of Uganda in 1937.
- It was identified in birds (crows and columbiformes like doves and pigeons) in the Nile delta region in 1953. Before 1997, WNV was not considered pathogenic for birds, but then, a more virulent strain caused the death in Israel of different bird species, presenting signs of encephalitis and paralysis.
- In 1999, a WMV strain, believed to be one circulating in Israel and Tunisia, reached New York producing a large outbreak that spread across the United States and eventually across the Americas, from Canada to Venezuela.
- According to the WHO, human infections attributable to WNV have been reported in many countries in the world for over 50 years.
- WNV outbreak sites are found along major bird migratory routes.
- Today, the virus is found commonly in Africa, Europe, the Middle East, North America, and West Asia.
-Source: Indian Express