Nipah Virus in Kerala, Several Lives At Risk

According to the state government's announcement on Tuesday, two individuals lost their lives as a result of the Nipah virus, while two others have contracted the virus in Kerala's Kozhikode district. Chief Minister Pinarayi Vijayan confirmed the presence of Nipah virus infection in the district, stating in a Facebook post that among the four individuals whose saliva samples were tested, two tested positive for Nipah, while the other two tested negative.

The Chief Minister has urged the public to stay calm and follow health department guidelines in response to the Nipah virus outbreak in Kerala's Kozhikode district. There are currently two active cases in the district, involving a nine-year-old and a 24-year-old relative of one of the deceased individuals. Additionally, the Central government has dispatched a team of health experts to Kerala, confirming that the two recent deaths in the state were indeed caused by the Nipah virus. The first death occurred on August 30, involving a 44-year-old man, followed by a second death on September 11, which was a 40-year-old man.

Nipah Virus Back In India: Possible Reasons For Emergence & Spread 

The Nipah virus is a zoonotic virus that can be transmitted from animals to humans. It is primarily associated with fruit bats (flying foxes) as its natural reservoir. The virus can cause severe illness and has caused outbreaks in India and other countries in the past. While it's challenging to pinpoint specific reasons for Nipah virus outbreaks in India, several factors can contribute to its emergence and spread:

1. Bat-Human Interaction: The virus can be transmitted from bats to humans through direct or indirect contact with bat urine, saliva, or feces. In some cases, the consumption of fruits partially eaten by infected bats can also be a source of transmission.

2. Animal Reservoir: Bats are known to host the Nipah virus without getting sick. The presence of these bats in India and their proximity to human populations can increase the risk of transmission.

3. Deforestation and Habitat Loss: As humans encroach upon bat habitats through deforestation and urbanization, the likelihood of contact between bats and humans increases, facilitating virus transmission.

4. Agricultural Practices: Some agricultural practices, such as the cultivation of date palm sap, can create opportunities for virus transmission. Infected bats may contaminate date palm sap, and people who consume this sap can become infected.

5. Human-to-Human Transmission: Once the virus is introduced into human populations, it can spread from person to person through close contact. Inadequate infection control measures in healthcare settings can contribute to human-to-human transmission.

6. Delayed Recognition: Delayed recognition of the disease and a lack of awareness about the Nipah virus can hinder rapid containment efforts, allowing the virus to spread.

7. Healthcare Infrastructure: The capacity of the healthcare system to diagnose, manage, and contain infectious diseases like the Nipah virus is crucial in preventing outbreaks. A weak healthcare infrastructure can contribute to the spread of the virus.

8. Migration and Travel: The movement of infected individuals or carriers of the virus can lead to the spread of the disease to new areas.

9. Climate and Seasonal Factors: Environmental factors, such as temperature and humidity, can influence the behaviour of the virus and its vector (bats). Seasonal variations may impact the frequency of outbreaks.

10. Virus Mutations: Viruses can evolve and adapt over time. Mutations in the virus could potentially increase its ability to infect humans or enhance its transmission.

Preventing Nipah virus outbreaks requires a multi-pronged approach that includes public health measures, surveillance, awareness campaigns, and research into the virus's ecology and transmission dynamics. Effective surveillance and early detection are critical for preventing and containing outbreaks. Additionally, efforts to reduce human-bat contact and improve healthcare infrastructure are important for reducing the impact of Nipah virus outbreaks in India and other affected regions.

Nipah Virus Previous Outbreak As Per WHO

An isolated case of the Nipah virus was reported in Kozhikode district, Kerala, India, on September 4, 2021, marking the fifth outbreak of this zoonotic disease in the country. A 12-year-old boy with mild fever sought medical attention on August 29, leading to his transfer to multiple hospitals on August 31 as his condition worsened.

The Nipah virus on September 1 was confirmed in samples sent for testing. Tragically, the patient passed away on September 5, prompting a safe burial and cremation. On September 6, epidemiological investigations identified contacts, including healthcare workers and family members, who were placed in quarantine as a precautionary measure.

Nipah Virus WHO Risk Assessment

Nipah virus disease is an emerging zoonotic illness of significant concern in the WHO South East Asia and Western Pacific Regions. It is primarily associated with Pteropus fruit bats, commonly found in these areas. The virus was first identified during a 1998 outbreak in Malaysia and has since affected parts of Asia, including India, Bangladesh, Malaysia, and Singapore. Transmission can occur through contact with infected animals, consumption of contaminated food, or close contact with infected individuals. Past outbreaks followed a seasonal pattern linked to bat breeding and fruit harvesting, with a high case fatality rate ranging from 40 to 100%.

India experienced Nipah virus outbreaks in Siliguri (2001) and Nadia district (2007), both in West Bengal. Subsequent outbreaks in Kozhikode and Kochi districts of Kerala state (2018 and 2019) were likely linked to Pteropus bats. The current isolated case in a rural area of Kerala, where a 2018 outbreak occurred, is being managed with established outbreak control measures. India's past experience and capabilities in case identification, testing, management, contact tracing, and risk communication suggest a low risk at both national and regional levels.