Indian authorities are currently grappling with a rare outbreak of the Nipah virus, a pathogen that jumps from animals to humans, resulting in a deadly fever with a high mortality rate.
– Understanding the Nipah Virus –
The initial recorded Nipah outbreak dates back to 1998, when the virus spread among pig farmers in Malaysia. It acquired its name from the village where it was first identified. While Nipah outbreaks are infrequent, the World Health Organisation (WHO) has categorised it, along with diseases like Ebola, Zika, and COVID-19, as a priority for research due to its potential to trigger a global epidemic.
Nipah typically infects humans through contact with animals, contaminated food, or even direct transmission between people. Fruit bats are the natural carriers of the virus and are considered the primary source of subsequent outbreaks. Symptoms include a high fever, vomiting, and respiratory infections. Severe cases can lead to seizures and brain inflammation, ultimately resulting in a coma. Unfortunately, there is currently no vaccine available for Nipah, and the mortality rate varies between 40 and 75 percent depending on the public health response, as per the WHO.
– Previous outbreaks of Nipah –
The first Nipah outbreak claimed over 100 lives in Malaysia and necessitated the culling of one million pigs in an attempt to contain the virus. It also spread to Singapore, with 11 cases and one fatality among slaughterhouse workers who had contact with pigs imported from Malaysia. Since then, Nipah has predominantly been reported in Bangladesh and India, both of which witnessed their first outbreaks in 2001.
Bangladesh has experienced a significant burden, with over 100 Nipah-related deaths since 2001. India faced two early outbreaks that resulted in the deaths of more than 50 individuals before they were successfully controlled. Recently, the southern state of Kerala in India has recorded two Nipah-related deaths and four confirmed cases within the past month. In response, authorities have closed schools and initiated widespread testing. Notably, this marks Kerala's fourth documented series of Nipah cases in five years, with the virus claiming 17 lives during the initial outbreak in 2018. Kerala's past success in quelling these outbreaks stemmed from comprehensive testing and strict isolation measures for those in contact with infected individuals.
The emergence of zoonotic diseases, those that can jump from animals to humans, has increased over the past few decades. The rapid growth of international travel has facilitated the spread of these diseases. Additionally, human activities, including deforestation and industrial farming, have disrupted ecosystems and heightened the risk of viruses mutating to become transmissible to humans. As different species come into closer contact, the transmission of viruses is facilitated, leading to the potential emergence of new diseases with human transmissibility.
Climate change further exacerbates the situation, forcing many animals to migrate from their natural habitats to more hospitable areas. A 2022 study published in the scientific journal Nature warned about this phenomenon. Estimates from a 2018 study in the journal Science suggest that there are approximately 1.7 million unknown viruses in mammals and birds, with 540,000 to 850,000 of them possessing the capability to infect humans.
In summary, the Nipah virus outbreak in India underscores the ongoing threat posed by zoonotic diseases and highlights the need for global vigilance and research to prevent potential epidemics. The interconnectedness of our world, combined with environmental changes, demands a proactive approach to identify, monitor, and mitigate such risks.