The Nipah virus primarily transmits to humans through direct contact with secretions from bats, birds, or infected individuals; it does not spread through distant airborne transmission like Covid-19. According to the World Health Organization (WHO), the Nipah virus causes acute encephalitis and respiratory failure, with a high mortality rate of 40-75%.

Dr. Ma Thanh Phong, Head of the Respiratory Unit, Department of General Internal Medicine, Tam Anh General Hospital, TP HCM, explained that after entering the body through the mucous membranes of the nose, mouth, or digestive tract, the Nipah virus can enter the bloodstream and rapidly spread to the central nervous system.

In the brain, the virus causes inflammation of small blood vessels, brain swelling, and nerve cell damage. This mechanism leads to acute encephalitis symptoms in patients, such as high fever, severe headache, dizziness, drowsiness, altered consciousness, seizures, and can rapidly progress to coma within 24-48 hours.

According to WHO, encephalitis is the most dangerous and characteristic manifestation of Nipah virus infection. It is also the primary cause of death or long-term neurological sequelae in survivors.

In addition to neurological damage, the Nipah virus can affect the respiratory system. When the virus spreads to the lungs, it damages lung parenchyma and pulmonary blood vessels, disrupting gas exchange. In severe cases, rapidly progressive pneumonia leads to respiratory failure, significant oxygen deficiency, and requires early respiratory support. These symptoms are easily confused with many other viral respiratory diseases, but their progression is rapid and severe.

Compared to seasonal flu or common respiratory virus infections, lung damage caused by Nipah typically progresses faster and more severely, especially when it occurs concurrently with encephalitis, making treatment complex and significantly increasing the risk of multi-organ failure.

Dr. Phong advising on respiratory illnesses. Photo: Tam Anh General Hospital

Dr. Phong advising on respiratory illnesses. Photo: Tam Anh General Hospital

Currently, there is no vaccine or specific treatment for the Nipah virus. According to WHO recommendations, people should limit close contact with individuals exhibiting suspected respiratory symptoms, strictly adhere to hand hygiene, properly cover respiratory pathways when caring for patients, and proactively use personal protective measures in high-risk environments. Avoiding contact with secretions and sources of infection helps reduce the risk of Nipah virus infection and controls disease spread in the community.

The Nipah virus was first identified in 1999 in Malaysia and Singapore, causing over 100 deaths and necessitating the culling of approximately one million pigs. Since then, this virus has been considered a recurrent health threat in South Asia, particularly in Bangladesh and India.

A Nipah outbreak recently occurred in West Bengal, India, with two confirmed cases, three suspected cases, and over 100 people quarantined. On 28/1, India's Ministry of Health declared the outbreak controlled, but many countries have tightened airport screening to prevent virus entry.

Vietnam has not recorded any Nipah cases to date. The Ministry of Health has requested increased surveillance at border gates and within communities, while also advising people not to eat fruit bitten by bats or birds, and to avoid consuming unprocessed palm sap or fresh coconut sap.

Nhat Thanh