The History and Impact of Nipah Virus Outbreaks
Viral outbreaks have always caused chaos and destruction worldwide. For years viruses like Influenza, smallpox, measles, and many more have been a financial burden. The deadly Nipah virus is just one of the contagious zoonotic viruses that the world had to deal with in the 21st century. The deadly Nipah virus was initially discovered in 1998 during an outbreak among Malaysian pig breeders. The virus spread to Singapore via pigs in a matter of months. Although there haven't been any more outbreaks in Malaysia, since 2001 there have been periodical outbreaks in Bangladesh and India.
Outbreak history
Fruit bats, especially the Indian flying fox are considered to be the main source of transmission for this zoonotic virus. It poses a serious health risk as this infection can also be transmitted directly from person to person and through contaminated food. Different levels of intensity and death rates have been associated with Nipah virus outbreaks throughout history. A 40% fatality rate and approximately 300 cases were the result of Malaysia's first outbreak in 1998 killing more than 100 people.
Approximately 66 people died in Bangladesh and 45 people died in Siliguri, India, as a result of the second outbreak in the year 2001 with a fatality rate of 68%. The deaths reported from subsequent outbreaks in Nadia district, West Bengal (2007) and Kozhikode, Kerala (2018), were 50 and 17, respectively. In Kerala, the fifth and sixth outbreaks in the years 2019 and 2021, respectively were notable for being less dangerous and having no confirmed fatalities. Unfortunately, Kerala, India, saw its fourth outbreak of the Nipah virus in six years in August 2023 killing two people in a month. More than 700 people, including healthcare professionals, have already undergone infection testing.
Moreover, moving to demographics, with a male-to-female ratio of 4.5:1 in Malaysia, the virus mostly afflicted male adults with an average age range of 37-44 years due to their day-to-day contact with pigs. In fact, a 7:4 ratio of males to females was seen in Bangladesh, primarily affecting children under the age of 15. On the other hand, in Siliguri, India, a 1.4:1 female-to-male ratio was seen, where individuals over the age of 15 were infected the most.
Transmission and prevention
The average rate of transmission from person to person was 1.4%, while pig/bat contact was considered to be the main cause in 70-80% of cases. A multifaceted strategy is necessary to stop Nipah virus outbreaks. At present, there are no vaccines available for treating this deadly virus so it is important to consider alternate tactics. To overcome previous mistakes pig farms can be effectively cleaned and disinfected with the right detergents. The danger of transmission to humans can be decreased by immediately quarantining and, if necessary, slaughtering affected animals. Additionally, limiting animal mobility away from affected farms can stop the spread of this virus. Better animal management close to communities, which addresses the underlying cause of zoonotic illnesses can help to prevent the spread of this virus.
With changing consequences, Nipah virus outbreaks continue to be a problem for global health. Despite the devastation caused by previous outbreaks, recent incidents suggest increased awareness and reaction. To lessen the spread of this fatal zoonotic virus, diligent surveillance and improved animal management are crucial.