Looming Threat Of Nipah Virus Infection

A recent outbreak of Nipah virus infection among two healthcare professionals in India sparked a series of discussions on its spread in our country. It is one of the most dangerous yet under-discussed infectious diseases of recent times. Nipah (NiV) virus is a highly lethal zoonotic pathogen with high mortality and capable of causing severe illness and death in humans. As this infection has no specific treatment or effective vaccine, its outbreaks make it a serious concern for public health, specifically in South and Southeast Asia. 

It was first identified in Malaysia in 1998 among pig farmers. Since then, recurrent outbreaks have occurred in Bangladesh and India in recent times. Unlike many other viral infections, Nipah virus infection has a very high mortality rate, ranging from 40-75 per cent. In the past, its outbreaks were small in scale, but the illness severity and unpredictability make this infection very concerning. This virus can pass from animal to human, and then from human to human, and has the potential to cause a pandemic. 

Fruit bats 

As a zoonotic disease, fruit bats are a natural reservoir of the virus. Particularly, the Pteropus species of fruit bats carry this virus. Direct contact with infected animals, consumption of raw date palm sap, or exposure to bodily fluids of infected individuals can transfer this pathogen and cause illness. Increasing deforestation, environmental degradation, and rapid urbanisation have considerably increased human-animal interaction and the frequent transfer of zoonotic diseases such as Nipah. 

Owing to the rapid deforestation in recent times, the chances of human interaction with the wild animals have significantly increased as forests shrink and habitats are destroyed. The ecological imbalance owing to many reasons has significantly increased Nipah outbreaks in countries such as Nepal, India, and Bangladesh, where agriculture, wildlife, and human population closely interact. 

The high mortality rate of this infection is a real concern, unlike other viral infections with mild to moderate outcomes. The infection begins with a fever, headache, and muscle pain and progresses to acute respiratory illness and fatal encephalitis. Victims fall into a coma within days, with often a poor outcome. Even if the patient survives, they suffer from long-term neurological consequences such as seizures and personality changes that greatly affect their quality of life. 

At the same time, its high mortality rate causes both social and psychological impact, leading to panic, stigma, and isolation. The most at-risk population is healthcare professionals who work closely with the Nipah patient, particularly in a crowded hospital setting. Owing to overstretched healthcare settings and poor infection control mechanisms, chances of human-to-human transmission are high in those settings. 

The overstretched healthcare system and inadequate infection control often lead to the spread of the disease unnoticed, and also due to inadequate laboratory capacity, poor surveillance mechanisms, and inadequately trained human resources to detect and manage outbreaks early. Delayed diagnosis and inability to manage it effectively often lead to increased fatalities and spread of infection. 

The place from where outbreaks usually begin is often rural areas, making it more complex due to poor healthcare infrastructure and inadequate awareness about zoonotic illnesses. Traditional practices and behaviours, such as consuming raw palm sap or close contact with livestock, often increase the chances of infection spreading. It is important to note that traditional behaviour is often difficult to change; hence, we need a strong public health education system, community engagement, and prevention efforts to reduce such outbreaks in the future. 

The Nipah virus infection has no specific antiviral medicines or vaccine, making it more dangerous; treatment is primarily symptomatic and supportive. Only symptomatic treatment makes this viral infection fatal once infection occurs. The lack of sufficient numbers of personal protective equipment in hospital settings also poses a risk of infection spread among the healthcare providers. 

Although the World Health Organisation has listed this virus as a priority pathogen, the research on medicines or vaccines for this virus is alarmingly slow. The pharmaceutical companies have given less priority to the development of medicines for this infection, mainly due to limited commercial interest, high research costs, and only sporadic outbreaks. This has left future outbreaks to be more catastrophic. 

The outbreaks have both economic and social implications besides medical. It not only disrupts local economies but also causes restrictions on movements and closure of markets due to fear of contagion. This greatly affects livelihoods, especially in developing economies where agriculture is the primary source of income. In the past, outbreaks of Nipah have caused the collapse of pig industries and have affected farmers financially for a long time. 

Psychological effects 

The psychological effects of such a stigma and discrimination against victims or healthcare workers further complicate the problem. Hence, it is not a mere medical problem but has a complicated development and governance challenges. It has less potential to be a global epidemic; however, it represents a warning signal and offers a great opportunity to governments to act proactively and be prepared for outbreaks of viral infections in the future. It is, therefore, essential to acknowledge the importance of strengthening disease surveillance, investment in research, environmental conservation to disrupt close human-animal interaction, community awareness, and health infrastructure strengthening. 

Due to open borders, climate change, and a shared ecosystem, we are not immune to future outbreaks. Hence, it is time to invest in preparedness rather than spending on future emergency response. The threat of the Nipah virus infection is not only due to its high mortality, but also has exposed our unpreparedness. Hence, all stakeholders should be more vigilant, invest in preparedness, and cooperate to tackle this silent threat to prevent it from becoming a future global health disaster. 

(Dr. Lohani is the clinical director at the Nepal Poison Information Center. lohanis@gmail.com)