Nipah - Sensible Precaution is Better than Panic
As the state is once again gripped by a fresh threat of the dreaded Nipah, it is most essential not to panic but explore rational measures to prevent the virus from spreading. A quick assimilation of the facts would provide an insight to avoid unnecessary rumours, misguiding information and also to secure immediate medical assistance in suspected cases of infection.
What is Nipah virus ?
Nipah virus (NiV) is an emerging zoonotic paramyxovirus that causes severe and often fatal disease in pigs and humans according to WHO. The virus is carried by fruit bats of the Pteropodidae family and was first identified during an outbreak of the disease in 1998 extending to 1999 in Malaysia and Singapore.
Typically, human infection presents as an encephalitic syndrome marked by fever, headache, drowsiness, disorientation, mental confusion, coma, and potentially death. Symptoms generally appear 5-14 days after exposure to Nipah
Signs and Symptoms
The virus gives off no obvious symptoms, infecting people and remaining dormant until it finally develops into fatal complications.
The Nipah Virus can be caught in humans without showing any signs of symptoms that the individuals have been infected. However experts advise to look out for the following signs :
fever and headache, myalgia (muscle aches), sore throat, vomiting, dizziness and/or acute respiratory syndrome or atypical pneumonia.
How can the virus be detected ?
Nipah virus infection can be diagnosed with clinical history during the acute and convalescent phase of the disease. The main tests used are real time polymerase chain reaction (RT-PCR) from bodily fluids and antibody detection via enzyme-linked immunosorbent assay (ELISA).
Other tests used include polymerase chain reaction (PCR) assay, and virus isolation by cell culture.
How dangerous is Nipah?
Encephalitis, inflammation of the brain, is a potentially fatal complication of Nipah virus infection. Respiratory illness can also be present during the early part of the illness. Nipah-case patients who had breathing difficulty are more likely than those without respiratory illness to transmit the virus.
Is it contagious?
The transmission of this fragile virus through the air is not possible. This contagious virus can only be transmitted through a direct contact with the infected bats, pigs, or from other NiV-infected people.
Can it spread through water ?
In Bangladesh, human cases have been linked to drinking unpasteurized date palm sap (juice) since the virus can thrive in sugar rich solutions.
The secretions or body fluids from the affected animals or people may contaminate water and render it harmful in places where Nipah is detected. Hence it's advised that wells and water bodies should be properly covered, treated water should be used for body sanitation and boiled water should be used for drinking and cooking.
Does it spread through chicken ?
Nipah virus can be transmitted to humans after consumption of food contaminated by bat saliva or urine. Nipah virus can cause disease in domestic animals like pigs, chicken and more as well. It would be beneficial to ensure that the food including chicken meat is not contaminated before consuming.
Since the virus was identified in 1999, it hasn't made the jump to chickens, according to the Centers for Disease
Control and Prevention. Also the "Manual on the Diagnosis of Nipah Virus Infection in Animals," issued by the Food and Agriculture Organization of the United Nations makes no mention of chicken or poultry at all.
How does it spread to humans ?
Transmission of Nipah virus to humans may occur after direct contact with infected bats, infected pigs, or from other NiV infected people. Person-to-person transmission of Nipah virus in Bangladesh and India is regularly reported. This is most commonly seen in the family and caregivers of Nipah virus-infected patients.
Transmission also occurs from direct exposure to infected bats. A common example is consumption of fruits contaminated with infectious bat excretions.
Humans can shed Nipah virus in respiratory secretions, saliva, and urine, and contact with respiratory secretions is thought to be the main route of spread from human to human.
Is there a cure ?
There are currently no vaccines or drugs approved for human use according to WHO. Studies in small-animal models of NiV infection suggest that antibody therapy may be a promising treatment.
There is no cure for the Nipah virus. Instead, people who are infected are treated with intensive supportive care, which includes making sure the person stays hydrated, and treating any nausea or vomiting along with addressing encephalitis or respiratory issues.
Do people who survive NiV infection recover fully?
Most people who survive acute encephalitis make a full recovery, but long term neurologic conditions have been reported in survivors.
Approximately 20% of patients are left with residual neurological consequences such as seizure disorder and personality changes. A small number of people, suffer a relapse or develop delayed onset encephalitis, after showing signs of recovery.
How the bats have turned carriers recently ?
In the words of Merlin Tuttle, American ecologist, founder & executive director of Merlin Tuttle’s Bat Conservation, “Virtually every animal species that has been carefully studied has some virus of potential risk to other species.
The virus that is present in the bats get virulent when the mammals are stressed out , mostly due to human-induced factors. A WHO report on Nipah Virus Infection states that “there is strong evidence that emergence of bat-related viral infections communicable to humans and animals has been attributed to the loss of natural habitats of bats.” It further adds, “As the flying fox habitat is destroyed by human activity the bats get stressed and hungry, their immune system gets weaker, their virus load goes up and a lot of virus spills out in their urine and saliva.”
Harming the bats is not a remedy
It's not confirmed that fruit bats are behind the spread of Nipah virus in Kerala. Only preliminary investigation by the health department identified bats a possible carriers of virus as cited in a previous circular from the Department of Animal Husbandry.
Bats are human friendly and a much useful species for the balance of our ecosystem.
Culling or killing of these animals would lead to their extinction which in turn would inflict serious damages to the ecological balance and thereby to humans. Our villages have always been home to different species of bats which had never posed a threat to human life. We need to identify the reasons behind the recent migration of bats to farms and populated areas - including climate changes and human induced habitat loss - and rectify those issues first. People should protect themselves through preventive measures including maintaining the surroundings clean and dry and abstain from any attempts to harm the animals.
How to prevent infection?
The precautions that can be useful include:
Avoid close (unprotected) physical contact with infected people
Wear NH95-grade and higher masks while in close contact with the infected.
Wash hands regularly with soap
Avoid consuming partly eaten fruits or unpasteurised fruit juices
Avoid being around animal farms that are not disinfected
Thoroughly wash and peel fruits before consuming
Maintain personal hygiene in the family as well as clean surroundings.
Cover your household properly; especially the water resources to avoid contamination.
(The author is Director, TGL Foundation, Editor Anthropology Today- the Intl Journal, Sr Dir, FWO)