Sign In
Learn bits
Science & Tech.
Mahesh

10/05/24 15:14 PM IST

West Nile fever cases detected in Kerala

In News
  • The Kerala government  said that cases of West Nile fever have been reported from three districts in the state – Thrissur, Malappuram and Kozhikode.
West Nile Fever virus 
  • The West Nile Virus (WNV) is a mosquito-borne, single-stranded RNA virus.
  • It is a flavivirus and is related to the viruses that cause Japanese encephalitis and yellow fever.
  • Culex species of mosquitoes act as the principal vectors for transmission.
  • Infected mosquitoes spread the disease 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 Centers for Disease Control and Prevention (CDC), it does not spread “through eating infected animals, including birds.”
  • The CDC notes that the incubation period for WNV disease is typically 2 to 6 days, but can range from 2 to 14 days, and can be several weeks in immunocompromised people.
Symptoms
  • 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.
  • For them, the symptoms include fever, headache, fatigue, body aches, nausea, rash, and swollen glands.
  • It is estimated that approximately 1 in 150 persons infected with the West Nile Virus will develop a more severe form of disease…
  • Recovery from severe illness might take several weeks or months. Some effects to the central nervous system might be permanent.
  • It usually turns fatal in persons with comorbidities and immuno-compromised persons (such as transplant patients).
  • But the death rate is relatively low compared to Japanese encephalitis, which shows similar symptoms.
Preventive measures
  • No WNV-specific prophylaxis, treatment or vaccine is available.
  • Only supportive treatments are given to neuroinvasive WNV patients.
  • Health authorities globally advise for personal protective measures to reduce the risk of mosquito bites, such as using mosquito repellents.
  • Public health departments are to also ensure larval source reduction, especially at breeding and resting sites for the mosquito vectors.
  • In most countries, the peak for WNV infections generally coincides with the period when mosquito vectors are most active and the ambient temperature is sufficiently high for virus multiplication.
  • Since WNV outbreaks in animals precede human cases, the establishment of an active animal health surveillance system to detect new cases in birds and horses is considered essential.
Why West Nile ? 
  • 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 deaths of different bird species in Israel, presenting signs of encephalitis and paralysis.
  • In 1999, a WMV strain, believed to be one circulating in Israel and Tunisia, reached New York and produced a large outbreak that spread across the United States and eventually across the Americas, from Canada to Venezuela.
  • 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.
  • In India, antibodies against WNV were first detected in humans in Mumbai in 1952 and virus activity has since been reported in southern, central, and western India.
  • WNV has been isolated in India from Culex vishnui mosquitoes in Andhra Pradesh and Tamil Nadu, from Culex quinquefasciatus mosquitoes in Maharashtra, and from humans in Karnataka.
Source- Indian Express

More Related Current Affairs View All

21 Sep

India Achieves Tier 1 Status in Global Cybersecurity Index 2024

' India has secured Tier 1 status in the Global Cybersecurity Index (GCI) 2024, published by the International Telecommunication Union (ITU).' The GCI is a comprehensive assessm

Read More

21 Sep

A new White Revolution

'Operation Flood, launched in 1970, ushered in the White Revolution and transformed the dairy sector in India.' Dairy cooperatives procured 660 lakh kg of milk per day in 2023-2

Read More

21 Sep

Changes in Canada’s international work permit system

'Canadian Prime Minister Justin Trudeau announced changes to the country’s international work permit system, aiming to reduce the number of immigrant workers in Canada.'

Read More

India’s First Ai-Driven Magazine Generator

Generate Your Custom Current Affairs Magazine using our AI in just 3 steps