The Viral Fear
Nipah is a highly contagious and deadly virus first identified in 1999 when pig farmers in Malaysia and Singapore fell very sick. NiV stands for Nipah Virus, a new disease that is transmitted to humans from animals. The natural hosts for this virus are fruit bats, which may infect an intermediary — which could be a plant or an animal, consumption of which spreads the disease among humans.
The viral attack leads to acute respiratory trouble and fatal inflammation of the brain. Alternatively, an infected person may act as a carrier without exhibiting any symptoms, since the disease can spread from humans-to-humans as well. Earlier cases include:
● 1998 Malaysia — Through pigs. Infected 265 and killed 105 persons. About 1.1 million pigs had to be culled ● 1999 Singapore — Outbreak of encephalitis and pneumonia, 11 people infected
● 2001 Siliguri, Bengal — 45 people died from 66 reported cases
● 2004 Bangladesh — Infected fruit bats via date palm. Mortality rate exceeded 70%
● 2007 West Bengal — Five deaths reported from Nadia
There are 2 genotypes of Nipah — ‘NiV-M’ and ‘NiV-B’. Most sequences from Malaysia belong to the genotype NiV-M, whereas sequences from Bangladesh were of NiV-B genotype. The incubation period of the NiV-B strain is 8 days and of NiV-M strain is 6 days. The maximum period for both the strains is 21 days. Both the strains have high fatality rate between 60% and 85%, say scientist. The transmission patterns of the 2 strains are different. Malaysia has well-defined piggeries where pigs get infected from the bats. The infection amplifies in them and subsequently transmits to humans. The Kerala virus is in the 97.8 – 97.9% similarity close to the Niv-B genome sequence. Transmission modes include:
● Ingestion (if a human eats a fruit coming in contact with the fruit bat-infected saliva)
● Inhalation (if a human inhales or accidentally ingests tiny droplets of the infected urine of the fruit bat
● Only a small portion of the fruit-eating bats carry the virus
Human organs affected by Nipah virus include brain, lungs and kidneys
Symptoms include fever, headache, dizziness, vomiting, breathing trouble, brain swelling, drowsiness, disorientation and delirium. A patient can fall into coma within 48 hours of being infected.
There is no vaccine for either humans or animals. According to the World Health Organization the primary treatment for human cases is intensive supportive care.