Nipah Virus Infection (NiV)


    In Context

    • Scientists at Pune’s Indian Council of Medical Research – National Institute of Virology were able to detect the presence of IgG antibodies against Nipah virus infection (NiV) in 51 bats that were captured from Karnataka, Kerala, Tamil Nadu and Puducherry.

    What are Antibodies?

    • Antibodies are specialized Y-shaped proteins made by the immune system. They help fight disease by detecting viruses, bacteria, and other pathogens (disease-causing microorganisms) and working to destroy them. 
    • They are produced and released from B cells, which are lymphocytes involved in the immune system, and also called immunoglobulin.

    Image Courtesy: Kyowa Kirin

    Types of Antibodies

    They are classified into IgG, IgM, IgA, IgD, and IgE.

    • IgG: It is the main antibody in blood and it has a powerful ability to bind to bacteria and toxins, and thus it takes on an important role in the biological defense system.
      • It is the only isotype that can pass through the placenta, and IgG transferred from the mother’s body protects a newborn.
    • IgM: It is constructed of five units of basic Y-shaped structures and is mainly distributed to the blood. Produced first upon pathogen invasion by B cells, IgM has a key role in the initial immune system defense for protecting the body.
      • The B-cell, also called B-lymphocyte, is a type of white blood cell that plays a significant role in protecting your body from infection.
    • IgA: IgA is mainly present as monomers (the shape of a single Y), but it forms dimers (a combination of 2 Ys) in secretions such as bowel fluid, nasal discharge, and saliva, to prevent bacterial invasion from a mucous membrane. 
    • IgD: It is present on the surface of B cells and it is reported to play a role in the induction of antibody production and the prevention of respiratory tract infections.
    • IgE:  IgE was originally related to immunity reactions to parasites. By binding to mast cells, IgE is believed to be involved in allergies such as pollinosis.

    Nipah Virus (NIV)

    • About:
      • It is a zoonotic virus (it is transmitted from animals to humans) .
      • The organism which causes Nipah Virus encephalitis is an RNA or Ribonucleic acid virus of the family Paramyxoviridae, genus Henipavirus, and is closely related to Hendra virus.
      • The case fatality rate is estimated at 40% to 75%. This rate can vary by outbreak depending on local capabilities for epidemiological surveillance and clinical management.
      • The virus can also cause severe disease in animals such as pigs, resulting in significant economic losses for farmers.  
    • Past Outbreaks 
      • Nipah virus was first recognized in 1999 during an outbreak among pig farmers in Malaysia when pigs in Malaysian farms came in contact with the bats who had lost their habitats due to deforestation.
      •  The disease has also been identified periodically in eastern India.
    • In subsequent outbreaks in Bangladesh and India, consumption of fruits or fruit products (such as raw date palm juice) contaminated with urine or saliva from infected fruit bats was the most likely source of infection.
    • It has caused annual outbreaks in Malaysia, Bangladesh and other countries in South-East Asia including India. 
    • Transmission:
      • The disease spreads through fruit bats or ‘flying foxes,’ of the genus Pteropus, who are natural reservoir hosts of the Nipah and Hendra viruses. 
      • The virus is present in bat urine and potentially, bat faeces, saliva, and birthing fluids. 
      • The virus is transmitted to people from animals and can also be passed on through contaminated food or directly from person to person
      • Human-to-human transmission of the Nipah virus has also been reported among family and caregivers of infected patients.
    • Symptoms:
      •  In infected people, it causes a range of illnesses from asymptomatic (subclinical) infection to acute respiratory illness and fatal encephalitis
    • Treatment:
      • There are currently no drugs or vaccines specific for Nipah virus infection although WHO has identified Nipah as a priority disease for the WHO Research and Development Blueprint.  
      • Intensive supportive care is recommended to treat severe respiratory and neurologic complications.
    • Preventive Measures: 
      • Raising awareness about its spread & transmission.
      • Reducing the risk of bat-to-human transmission
      • Reducing the risk of animal-to-human transmission by using Gloves and other protective clothing.