Nipah Virus Tryst with Destiny
The Nipah scare in coastal Kerala was yet another reminder of how our generation’s most perilous nemesis maybe miniscule but never short of menacing, explores Abhinav Singh.
The sudden Nipah virus outbreak in Kerala had befuddled doctors across the country. With the first case reported in mid-May, doctors, microbiologists and virologists ensued a race against time to prevent the virus from becoming a menacing threat to the population. The zoonotic Nipah virus brought back the haunting memories of Ebola, Zika and H1N1 (Swine Flu), which had turned into serious epidemics claiming numerous valuable lives.
First reported in the Sooppikkada village in Changaroth Gram Panchayat of Kozhikode's Perambra, the virus spread to the nearby districts of Malappuram and Wayanad in no time. With a mortality rate as high as 74.5 per cent, the virus claimed 18 of the 20 lives infected.
Dr Anoop Kumar, a Critical Care specialist at a private hospital in Calicut, was the first to recognise the unnatural symptoms in a patient, later identified as Nipah virus. "The patient had symptoms of acute encephalitis but the blood pressure was rising and pulse rate was swinging, instead of dipping. The condition was quickly developing and we had to act fast. When we were sure that the condition is unforeseen, we first separated him from other patients and sent his samples for examination so that a suitable treatment could be undertaken – it all happened very fast. Time is crucial in such situations," he said when quizzed about detecting the fatal virus.
Due to the virus outbreak, Kerala State Athletics Association (KSAA) postponed the Dr Tony Memorial 62nd Kerala State and Olympian Suresh Babu Memorial 8th Kerala Athletics Championship, scheduled to be held on June 5 and 6. The Public Service Commission had also postponed all its exams, scheduled to be held till June 16. Also, some Arab nations including Qatar have banned Mangoes from Karnataka and Kerala where the farmers and sellers had pinned their hopes on the Ramadan sales – the ban has irrevocably hurt business.
Source, symptoms & history
Nipah is not new though it was only identified in 1998, when it first infected humans in Malaysia's Sungai Nipah village. In the 1970s, intensive pig farming flourished in Malaysia, with farmers expanding farmlands into wild areas. Nipah, it turns out, was already present in fruit bats. Bats infected pigs, and the pigs infected people. 265 people were infected, and 40 per cent succumbed. Euthanasia was conducted on a massive scale on pigs, almost one million pigs were culled to contain the virus, jeopardising the local source of income and livelihood. In India too, cases of Nipah virus were reported from Bengal's Siliguri in 2001 and Nadia in 2007 with around 47 deaths being reported. Neighbouring Bangladesh has also witnessed cases of Nipah outbreak.
Fruit Bats of the genus Pteropus are the natural host of NiV and these infected bats shed virus in their excretion and secretion. Nipah is a near perfect example of an emerging infectious disease. Its history and evolution follow the pattern of almost every new virus and, therefore, it becomes difficult to distinguish as the symptoms are quite similar to influenza fever and muscle pain.
"Human bodies are not capable of making antibodies against these viruses, especially when they come from animals, birds, rodents and insects. Nipah is a relatively new virus and there is a need of understanding it better; patients have to be cautious and tell the doctors their medical history clearly," said Professor P Seth, former Microbiologist, AIIMS.
Professor Seth also said that, by and large, the symptoms include fever, headache, drowsiness, disorientation and mental confusion which can lead to coma and potentially prove to be fatal. It has been said that the man who was first infected with the NiV in Kerala must have eaten a fruit infected by the bat, which thereafter caused a domino effect, infecting other people too.
The virus is transmitted directly/indirectly by consuming fruits eaten by infected bats and birds, whereas transmission of NiV to humans may occur after direct contact with infected bats and pigs. Presumably, pigs may become infected after consumption of partially bat eaten fruits that are dropped in pigsties. Nosocomial transmission is another means of spreading of the virus amongst humans.
While the Nipah virus may not have spread beyond Kerala, concerns over it have spread across the country with several states investigating suspicious cases and issuing advisories on precautions and travel to Kerala.
The state health ministry of Madhya Pradesh on May 25, issued an advisory against eating fruits that have fallen on the ground or appear to have animal teeth or claw marks. "People should avoid going to areas that might have bats. Stay away from suspected infected persons," said Health Services Director BN Chouhan.
The Bihar government issued a Nipah virus alert on May 26, asking people to take precautions. Chief Minister Nitish Kumar, on May 28, said that there is a need to create awareness among people about the deadly virus and that they should postpone travel plans to Kerala in the meantime.
The Delhi government, while issuing a health advisory for the Nipah virus, said that no incidence of the infection has been reported in the national capital yet. The Directorate General of Health Services said that the infection spread from animals to humans and people should be careful.
Panic gripped Himachal Pradesh when several bats were found dead at Government Senior Secondary School in Barmapapri in Sirmaur district, last month. However, tests at the National Institute of Virology in Pune ruled out that the presence of Nipah virus in the bats.
Similarly, in Telangana, two persons, including one who had visited Kerala recently, were hospitalised on May 25, with suspected Nipah virus infection. The state health authorities, without taking any chances, have sent their samples to Pune for investigation.
The Rajasthan Government issued an advisory asking people not to travel to affected parts of Kerala and for officials to maintain caution.
Safety of healthcare workers
After a healthcare worker, Lini Puthussery, died of the Nipah virus while attending to infected patients, the ministry had issued a separate advisory for healthcare personnel, advising them to wash hands thoroughly for 20 seconds after contact with a sick patient, practice precautions for infection control, limiting the use of injections and sharp objects. For aerosol-generating procedures, personal protective equipment such as individual gowns (impermeable), gloves, masks and goggles or face shields and shoe cover have been ascribed and the procedure should be performed in an airborne isolation room. All non-dedicated, non-disposable medical equipment used for patient care should be disinfected as per manufacturers' instructions and hospital policies.
Antibodies: A way out
India has reportedly procured 50 doses of an antibody from Australia, which will help combat the virus. The Indian Council for Medical Research (ICMR) had reached out to the University of Queensland, Australia, which has developed an antibody to combat and 'neutralise' the virus. The Human Monoclonal Antibody (M 102.4) is a non-patented drug, developed by Dr Christopher C Broder from Australia.
Samples collected from patient autopsies showed histologic ﬁndings of damage, mainly in arterioles and capillaries. The brain was the most severely affected organ, but other organs, including the lungs, the heart and the kidneys, were also affected.
It is important to note that the antibody can only neutralise the effects of the virus and is not a vaccine. In Australia, it (vaccine) has only been tried in vitro (happening outside the body in artificial conditions, often in a test tube) and has been found to be effective.
The way ahead
Health authorities have drawn up a list of 2,000 people who had come in contact with the Nipah-affected persons to monitor their health conditions. A control room has been opened at the Kozhikode medical college which will update the health conditions, the official said.
Also, efforts are on to trace the source of the first outbreak in Sooppikkada village. Virology experts and officials from the National Centre for Disease Control, led by its Director Sujeet K Singh have already visited Perambra. The help of experts of the Animal Husbandry Department had been sought to understand the exact cycle of infection.
Despite having the highest literacy rate and best healthcare facilities among other states of the country, Kerala did not have any lab facility available for the testing of the infected patients and had to rely on labs at the National Institute of Virology in Pune and the Manipal Centre for Virus Research (MCVR) in Karnataka for confirmation.
Though this outbreak has been controlled, the future beholds many more obstacles. Zoonotic viruses and diseases are on the rise, as this recent brush with Nipah has confirmed. The 2018 annual review of the WHO R&D blueprint list of priority diseases, indicates that there is an urgent need for accelerated research and development on the Nipah virus. There's a need to up the ante and start funding R&D more vigirously for disease outbreaks, to come up with a suitable action plan, before another epidemic strikes.