About the infection:
Nipah virus (NiV) encephalitis is an emerging infectious disease of public health importance in the WHO South-East Asia Region. Bangladesh and India have reported human cases of Nipah virus encephalitis. Indonesia, Thailand and Timor-Leste have identified antibodies against NiV in the bat population and the source of the virus has been isolated.
The beginning:
Nipah virus infection was first recognized in a large outbreak of 265 suspected cases in peninsular Malaysia during September 1998 to April 1999. Most patients had contact with sick pigs or had been in close physical contact with Nipah virus infected patients and then presented primarily with encephalitis. The outbreak was initially thought to be due to Japanese encephalitis, but it was later identified as Nipah virus encephalitis. This outbreak caused widespread panic and fear in Malaysia leading to considerable social disruptions and tremendous economic loss because of the mass culling of over one million pigs. In addition, eleven abattoir workers in Singapore developed a febrile illness caused by Nipah virus during March 1999 following close contact with imported pigs from Malaysia.
The Indian Story:
India reported two outbreaks of Nipah virus encephalitis in the eastern state of WestBengal, bordering Bangladesh, in 2001 and 2007. Seventy one cases with 50 deaths (70% of the cases) were reported in two outbreaks. During January and February 2001, an outbreak of febrile illness with neurological symptoms was observed in Siliguri, West Bengal. Clinical material obtained during the Siliguri outbreak was retrospectively analyzed for evidence of NiV infection.
Are bats the problem?
Having been around for millions of years, bats have probably carried infectious diseases for nearly as long, Gurley says. Several bat species can carry viruses that are deadly to humans, including Ebola, Marburg, SARS and Nipah, without getting sick themselves (SN: 3/9/13, p. 10).
But scientists say that villainizing bats is not the answer. “They’re a crucial part of their ecosystems,” Gurley , an infectious disease epidemiologist at Bloomberg Institute, USA says. “They are also really important pollinators.”
Several factors have increased the chance of bat-borne viruses being passed humans, including development that has encroached on the bats’ natural habitats.