Different departments of Kerala government — Forest, Health, Animal Husbandry, and Local Self-Government — will work together to implement it
Published Jul 23, 2024 | 11:00 AM ⚊ Updated Jul 23, 2024 | 11:00 AM
Fruit bats (flying foxes) are considered to be the carriers of the Nipah virus in Kerala. ( Mini Anto Thettayil)
A 14-year-old boy died of Nipah virus (NiV) infection in Malappuram district of Kerala on Sunday, 21 July. The boy showed signs of Acute Encephalitis Syndrome, with sudden onset fever and neurological dysfunction.
Common symptoms of this disease are altered mental status, confusion and seizures, even though some of the infected may show no symptoms at all. Kerala has seen cases of this infection in 2018, 2019, 2021 and 2023.
The state government is now set to heighten surveillance and has unveiled a year-round calendar to deal with this virus.
NiV first emerged in Kerala in 2018, causing significant concern. The World Health Organization defines NiV as a zoonotic virus transmitted from animals to humans.
It can also be transmitted through contaminated food or directly between people. In infected people, it causes a range of illnesses from asymptomatic (subclinical) infection to acute respiratory illness and fatal encephalitis.
Kerala’s year-round calendar adopts a “One Health” approach, emphasizing inter-departmental collaboration, and recognizing the need to conserve the environment, animal and plant health as part of the strategy to protect human health.
Different departments of the state government, including Forest, Health, Animal Husbandry, and Local Self-Government, will work together to implement the plan.
The year-round calendar is a schedule of activities and measures designed to prevent the spread of the Nipah virus and manage any potential outbreaks. It includes continuous monitoring of wildlife, especially bats, which are known carriers of the virus, regular health check-ups in high-risk areas, and timely awareness campaigns to educate the public on preventive measures.
Talking to South First, a health official said, “We have learned from previous outbreaks that a fragmented response is inadequate. By uniting different departments and agencies, we can ensure a comprehensive and timely response, minimizing the impact on public health and the economy.”
It has been ascertained that fruit bats of the Pteropodidae family are the natural hosts of the NiV. In the case of Kerala, researchers also found the presence of NiV among fruit bat samples.
“Though most of the reports are from Kozhikode and Wayanad districts, the presence of NiV has also been detected in bats in Ernakulam, Idukki and Malappuram districts,” reads an excerpt from the document of the health department on NiV.
“Studies are still underway in districts other than these five districts. Perhaps when such studies are completed, the presence of NiVs in bats may be detected in all districts of Kerala,” the document noted.
“Although rare, we have already witnessed these viruses reaching humans and causing a lot of deaths and panic. Therefore, the necessary measures need to be implemented to prevent this virus from reaching humans, to identify it early, even in the rarest of its occurrences, and to save the lives of humans if there are chances of them getting infected.”
“The state health department hopes to perform scientific, efficient and exemplary work by preparing an annual calendar for Nipah prevention and systematic implementation of preventive measures based on that,” the document stated.
An excerpt from the action plan listing the dates for carrying out the Nipah awareness campaigns at respective districts. (Supplied)
Specific activities will be performed right through the year as part of the infection prevention plan: Surveillance and early warning, public awareness campaigns, research and development, community development and healthcare preparedness will become routinized.
A mock drill will be held in April, since the virus outbreak coincides with the time of year when fruit trees ripen in the state, between May and September. Bats are drawn to these trees at that time.
Nipah Awareness Week will be observed starting 1 May, so that the public is properly educated about measures to prevent the virus spread.
Week-long awareness campaigns will be held in all districts from 8 May to 7 September, starting from Kozhikode and culminating in Thiruvananthapuram.
The state government is also planning on an international conference in September, to bring together experts in the field.
According to the health department, the Nipah virus variant found in humans and bats in Kerala is genetically similar to the Nipah virus in Bangladesh. However, there is no evidence that it came from there.
There is also no glaring genetic difference between the Nipah virus detected in humans and bats in Kerala between 2019 and 2023. The department says mortality rate caused by this disease has fallen from 90 percent to almost 33 percent during this period.
“We haven’t had any definitive evidence as to how this virus, found in fruit bats, reaches humans. It is also yet to be ascertained whether any animals transmit the infection to humans by acting as intermediaries between bats and humans. Research work is in progress,” said an official of the Institute of Advanced Virology, Kerala.
The health department however is working on some assumptions.
“All the Nipah cases in Kerala took place between May and September. This is the time when the mating and breeding of bats takes place in the land. Moreover, it can be seen that almost all the fruits available in the land ripen at about this time. The presence of the Nipah virus in bats during breeding is very high and it might reach humans directly (contact with bats, use them for meat, etc.) or via fruits that are bitten by bats and discarded by them or through their excreta, by means of substances such as honey in banana stalks, or by animals that act as intermediaries,” says the document on NiV outbreak case study conducted by Kerala.
In the case of Malappuram, where a 14-year-old boy succumbed to NiV, it is suspected that the child ate hog plums from a nearby field, and the presence of fruit bats was confirmed there.
A preliminary assessment is that the fruit was the source of the infection, though this can only be confirmed after tests. After the latest incident, a team led by Dr Balasubramaniam of the National Institute of Virology, Pune, has arrived in the state to monitor bats.
Dr Anish T S, nodal officer, One Health Centre for Nipah Research told South First, “Catching, hurting, destroying and scaring bats can create conditions where viruses might reach more humans. The way out is continuous monitoring of fruit bat populations and other potential wildlife carriers, as well as regular health screenings in vulnerable human populations.”
(Edited by Rosamma Thomas)
