Context:
Kerala has once again reported the presence of the Nipah virus, marking the eighth emergence in as many years. While the state has become adept at containing the virus, critical knowledge gaps remain regarding how the virus spills over from bats to humans.
What is Nipah Virus (NiV)?
- Type: RNA virus from the Henipavirus genus, closely related to the Hendra virus.
- Nature: Zoonotic disease — transmitted from animals to humans.
- Natural Host: Fruit bats (Pteropus species), also known as flying foxes, are the natural reservoir.
Transmission Routes
- Direct contact with infected animals (especially pigs)
- Consumption of contaminated food (e.g. raw date palm sap)
- Human-to-human and animal-to-human transmission observed.
Symptoms of NiV Infection
- Acute respiratory illness
- Seizures
- Encephalitis (swelling of the brain)
- Confusion, coma, and potentially death
- Incubation Period
- Typically 4 to 14 days, but can extend up to 45 days in some cases.
- Fatality Rate
- 40% to 75%, among the highest for zoonotic infections
Why are NiV outbreaks recurring in Kerala?
- Endemic status of NiV in fruit bats in Kerala.
- Proximity of human settlements to forested areas, increasing human-bat contact.
- Robust healthcare surveillance in Kerala helps identify and report NiV outbreaks early.
- Other states may be underreporting or missing cases due to weaker surveillance.
