What is Nipah virus?
Nipah virus (NiV) infection is a newly emerging zoonosis that causes severe disease in both humans and animals. Zoonosis means a disease that can be transmitted to humans from animals.
The natural host of the virus is fruit bats of the Pteropodidae Family, Pteropus genus (fruit-eating species), according to WHO.
How does it spread?
Transmission of Nipah virus takes place through direct contact with infected bats, pigs, or from other NiV-infected people.
What are the symptoms of Nipah virus infection?
According to Centers for Disease Control and Prevention, infection with Nipah virus is associated with encephalitis (inflammation of the brain). An infected person shows symptoms of fever and headache within three-14 days of exposure and an incubation period of five to 14 days.
The clinical signs are fever, headache, dizziness and vomiting, followed by drowsiness, disorientation and mental confusion. More than 50 per cent of the patients faced a reduced level of consciousness and prominent brain-stem dysfunction. Some patients have a respiratory illness during the early part of their infections, and half of the patients showing severe neurological signs showed also pulmonary signs.
When was Nipah virus first identified?
Nipah virus was first identified in Kampung Sungai Nipah, Malaysia in 1998. The pigs were the intermediate hosts during that outbreak. Around 1.1 million pigs had to be killed to control the outbreak. However, it is not necessary to have an intermediate host during Nipah Virus outbreak.
When did Nipah Virus first occur in India?
In India, Nipah Virus affected the humans without any involvement of pigs. The first outbreak was observed in Siliguri, West Bengal in 2001. The second incident also emerged in Nadia district in West Bengal in 2007. Scientists have found that humans often contracted the disease by drinking raw date palm sap tapped directly from trees, a sweet treat that fruit bats also enjoy.
The virus claimed over 300 lives across Malaysia, Singapore, Bangladesh and India between 1998 and 2008, according to WHO.
Nipah virus infection around the world
Bangladesh recorded several Nipah outbreaks in humans almost every year from 2001 to 2013. The virus has been detected in Cambodia, Thailand, Indonesia, Madagascar in Southern Africa and Ghana in West Africa on fruit bats or bats seropositive to NiV antibodies, according to a 2013 ICMR-sponsored research paper.
What are the treatments of Nipah virus?
According to WHO, there is no vaccine currently available for either humans or animals and NiV-infected patients are currently limited to supportive care. People have also been cautioned that they should not consume fruits that have fallen on to the ground.
Doctors' take on Nipah virus outbreak
Atul Gogia, senior consultant, Department of Medicine, Sir Ganga Ram Hospital, said: "Nipah virus is just another viral infection that affects the respiratory and central nervous systems with symptoms like drowsiness. Like most other viral infections, Nipah, too, has no treatment and can only be managed through intensive supportive care."
The senior doctor said people living in areas inhabited by bats or wildlife animals should be alert as there can be other infections that can afflict them.
While he did not rule out the possibility of an infected person travelling to other parts of the country and spreading the disease, he said there is no threat to other parts of the country, including North India and Delhi.