Nipah virus infects humans when they drink date palm sap contaminated by infected fruit bats or when they come in direct contact with the secretions of the infected bats.
World Health Organization
Once this virus finds its route into the human body, it can infect even more humans through “human-to-human” mode of transmission.
The reason why you should be taking Nipah virus infection seriously is that it has a fatality rate of 70-90%.
So, what can you do about it? What else should you know? How can you keep it from yourself? All your questions answered in this article. Read it through.
Specifically, You Will Learn In This Article-
A. Quick Facts about Nipah virus
- Nipah virus causes disease in both animals and humans, with high pathogenicity to the humans.
- NiV primarily affects the brain and can even go on to affect lungs, kidneys, and heart.
- CDC categorized Nipah virus as a critical potential biological weapon because of its:
- Ease of production & dissemination
- High virulence & mortality
- Nipah virus is continuously evolving and getting more infectious (acquiring more ways to infect) with each of its outbreak.
- Along with the brain, Nipah virus can also directly infect the neurons in the central nervous system.
B. Nipah Virus: What You Should Know [Infographic]
C. What is Nipah Virus?
Nipah virus infection (NiV) is the viral infection caused by Nipah virus. Nipah virus is a member of the family Paramyxoviridae, genus Henipavirus.
Specifically, genus Henipavirus consists of two species, out of which Nipah virus is the one and Hendra virus the other.
This very fact that Hendra virus, which has a close association with Nipah virus, resides naturally in flying fox (bats of the genus Pteropus) led to the discovery of fruit bats or flying foxes as the reservoir/source of Nipah virus too.
C1. How & Where It All Started?
Nipah virus is named after the Malaysian village; Sungai Nipah, where in 1999 it was detected for the first time in pig farmers and people living in close contact with pigs.
Although it had only caused mild disease in pigs, it nearly infected 300 and caused over 100 deaths in humans.
As a measure to prevent its outbreak, millions of pigs were then killed, which proved to be an effective solution too.
Possibly, the proximity of bat habitats and piggeries exposed the pigs to the contaminated urine, feces, and partially eaten fruits of bats. This led to an easy transmission of Nipah virus into pigs, followed by its spread into humans who were in close contact. This eventually led to the NiV outbreak.
D. Nipah Virus Symptoms
Nipah virus mainly affects your brain and causes inflammation (swelling) of your brain tissue, which scientifically is known as encephalitis.
Therefore, its symptoms are mostly similar to that of the mental & neurological disorders.
Precisely, this is what happens when Nipah virus infects a human-
1. Exposure to the virus.
2. The incubation period (of 5-14 days). It is the time-
- before the appearance of symptoms of NiV.
- when Nipah virus replicates itself to increase its number in order to survive the defensive nature of your immune system and to infect you more.
- your immune system kicks in, fights the virus, and produces cytokines such as interferon in the process, which makes the symptoms to become visible.
3. The appearance of Symptoms (for 3-14 days)
- Neurological signs
- Disorientation- to lose the sense of direction, personal identity, place, or time.
- Mental confusion
- Drowsiness- sleepiness
- Partial or complete loss of sensation
- Muscle weakness
- Personality changes
- Convulsions- involuntary muscular contraction
- Respiratory illness
- Shortness of breath
- Chest pain
In the severe cases, these symptoms can even progress to coma within the next 24-48 hours. Death can occur in up to 80% of the cases.
Nipah virus infection can also lead to the long-term persistence of the symptoms such as convulsions and personality changes.
Reportedly, the infection can as well stay inactive for years after the exposure, only to revive later on, when it can cause death too.
E. Nipah Virus Transmission
Transmission of Nipah virus occurs mainly:
- from contact with the excrement or droppings of infected fruit bats or pigs.
- when you consume contaminated raw date palm sap (a drink found in parts of Asia) infected by fruit bats (that host of Nipah virus).
- on contact with body fluids from the infected person such as nasal or respiratory droplets, urine, or blood.
During the initial outbreak of Nipah virus infection in Malaysia, transmission took place from:
- infected bats to the pigs, and then
- from infected pigs to the humans.
Later, when it resurfaced in Bangladesh and India, the human-to-human transmission was also reported.
The latest case of human-to-human transmission of NiV came from Kerala in India where a 28-year-old nurse providing medical assistance to NiV infected patient died.
The patients that she was treating had themselves gotten NiV from consuming contaminated date palm sap.
Moreover, exposure to the infected bats can also cause the direct transmission of Nipah virus from bats to humans.
Nipah virus infection is more frequent in India and Bangladesh due to the ability of the newer Nipah virus strain to infect humans in a lot more ways.
F. History of Nipah Virus Outbreaks
Fruit bats (fruit-eating species) of genus Pteropus act as natural host of Nipah virus and live throughout Asia and East Africa.
Here is a brief account of the locations where Nipah virus has been disastrous-
- 1999: Malaysia: carrier bats infected the pigs, which subsequently infected the humans.
- Cases: 276, Deaths: 106
- 2001: India: transmission of disease from bats to human through date palm sap followed by human to human
- Cases:66, Deaths: 45
- 2007: India
- Cases: 5, Deaths: 5
- 2001-13: Bangladesh
- Cases: 221, Deaths: 171
- 2018: India
- Cases: 18, Deaths: 16
According to the WHO, out of the total 477 cases reported during 1988-2008, 248 people were killed, setting the nipah virus fatality rate at 52%.
G. Nipah Virus Treatment
As of now, no effective treatment or vaccine is available for Nipah disease. The only mainstay is supportive care.
However, drug ribavirin may alleviate symptoms of convulsions, vomiting, and nausea.
On a brighter side, post-exposure therapy indicated that passive immunization using a human monoclonal antibody, which targets Nipah G glycoprotein, may be beneficial and can be the key to developing a viable treatment for NiV in the future.
H. Nipah Virus Prevention
The best way to prevent Nipah virus infection is by limiting your exposure to the factors that are known to be causing the disease.
- Avoid going near sick pigs or bat prone areas.
- Do not consume date palm sap if it is from the area where NiV is reported.
- Pig farmers living in places where bats are frequently seen should get their livestock inspected routinely.
- Avoid hospitals that treat Nipah virus infected patients but don’t follow standard hospital settings, to prevent nosocomial infection (human-to-human infection).
- Wear protective equipment such as gloves, gown, and facemask to avoid direct contact with body fluids from infected patients.
Follow the precautions listed above and stay cautious during February to May.
This is because NiV appears to be more of a seasonal phenomenon when bats reproduce and their young ones migrate, which consequently increases the risk of infection.
There is also a possibility for NiV to spread to other countries such as UK, UAE, Singapore, Sri lanka, and Australia through the travelers that visit south India.
Therefore, adopting these precautionary measures when you visit Nipah virus infected countries will ensure your safe visit.
Being watchful can help keep you protected from any potential NiV threat if you are in any way; directly or indirectly, linked to the fruit bats.
Are we going to see more Nipah virus outbreaks in future? what do you think? Let me know in the comments below.
Stay safe, Good luck! 🙂