Kerala is battling its fourth outbreak of the deadly Nipah virus, as the state has reported six cases till now, of which two recently succumbed to the infection. One person infected with the virus died this month while the other death occurred on August 30. Others infected are still under treatment as the administration tightens controls in the state.

On Monday, the state health minister, Veena George, confirmed that the recent “unnatural deaths” in Kozhikode district were caused by the deadly brain-damaging nipah virus. In the wake of the situation, the State Health Department has established core committees for surveillance, sample testing and research management, contact tracing, and patient transportation management.

This week, in a bid to curb the spread of a lethal virus, Kerala has temporarily closed certain schools and offices. Areas within Kozhikode with confirmed cases have been designated as quarantine zones. According to Union Health Minister Mansukh Mandaviya, the central government has also sent a team of four experts to Kerala in order to assist the state government in surveillance and reduction in the response time.

This is not the first time that the nipah virus has been found in the Kozhikode district of Kerala. Infact, this is the fourth such instance in the district since 2018. Here's what we know about this brain damaging virus.

An emerging virus

The first Nipah outbreak was detected in Malaysia in 1998, where the illnesses was caused by direct contact with sick pigs or their contaminated tissues. According to the World Health Organisation, "In subsequent outbreaks in Bangladesh and India, consumption of fruits or fruit products (such as raw date palm juice) contaminated with urine or saliva from infected fruit bats was the most likely source of infection." 

Speaking to BOOM, microbiologist Dr Umar Rashid Khan explained that the nipah infection is a zoonotic illness that is transmitted to people from animals like bats and pigs. It can also be transmitted through contaminated food. "It is an emerging virus, which means that it has been in the environment without bothering human beings so far but is now emerging as an infective agent due to mutations," he said.

Since it is an emerging infection, we cannot say much about its transmission rate, but it is around 50%-60%, Khan added. 

According to Dr Neha Gupta, an infectious diseases physician based in Gurgaon, the virus can also spread directly from person-to-person. "It can spread from both asymptomatic and symptomatic patients as its incubation period is between 4-14 days. The period can extend up to 45 days as well, in rare scenarios," she said.

The incubation period is the number of days between when a person is infected with something and when they finally might see symptoms. 

Symptoms and Diagnosis

According to Khan, the initial symptoms are similar to any viral infection, namely, headache, fever, running nose, sore throat and body ache. "It can also develop into serious symptoms like dizziness, altered senses where one is not able to communicate properly, breathlessness, seizures and even acute encephalitis," he said.

Encephalitis is a life-threatening disease which is caused due to inflammation of the brain. The virus, as Khan says, has a propensity towards brain receptors where it can cause the infection in extreme cases, induce coma in patients leading to death.

Gupta told BOOM that the rate of fatality in case of nipah infection is close to 50%-75%. "If a patient succumbs to encephalitis, the chances of saving them is extremely thin," she said. 

Talking about the diagnosis, Gupta said, "After we have enough clinical symptoms, we can go for molecular PCR (Polymerase Chain Reaction) test or CSF (Cerebrospinal Fluid) test. They can give accurate results within 7 days of infection. In case of these tests are not available, we can take antibodies test after 7 days of infection."

According to both the experts, there is no definitive treatment or vaccination for nipah infection available till now, due to which we only depend on symptomatic treatment. Symptomatic treatment refers to the medical therapy of a disease that only affects its symptoms, not its cause. It is usually aimed at reducing the signs and symptoms for the comfort and well-being of the patient.

Precautions

The nipah infection is not air-borne, rather it transmits through the droplets of the infected person. Therefore, it is important to maintain good hygiene and sanitisation. One should also refrain from consuming unwashed fruits and visiting areas of outbreak.

Lastly, as a word of advice, Khan suggested extra precautions for immuno-compromised patients, diabetic people and pregnant women. He said, "Our blood cells fight the viral infections, but sometimes some residue of infection could be left in our body. In the future, if that person encounters another immuno-compromised disease like cancer or undergoes organ transplant, then they become vulnerable to relapse of nipah infection."