MANY AIRPORTS IN Asia, Europe and the United States are vigilantly screening and securing their gateways from nipah virus – a zoonotic disease coming from a Malayan flying fox (Pteropus vampyrus), a Southeast Asian species of megabat that feeds on flowers, nectar and fruit. The World Health Organization (WHO) confirmed that nipah virus can be transmitted through several pathways, including animals to humans (through fruit bats via contaminated food) or directly between humans.
Already, the Department of Health (DOH) announced it is preparing for the possible entry of the virus following reported outbreaks in India and Bangladesh.
The virus is not new in the country as 17 cases had been detected in Sultan Kudarat in 2014 after some people ate horse meat, according to the DOH.
Outbreaks of the Nipah virus in pigs and other domestic animals such as horses, goats, sheep, cats and dogs were first reported during the initial Malaysian outbreak in 1999. The virus is highly contagious in pigs. Pigs are infectious during the incubation period, which lasts from 4 to 14 days.
No cases were seen after that and the DOH continues to monitor through its Epidemiology Bureau.
The DOH said seasonal outbreaks occur in Bangladesh and India, and there have been five confirmed cases in West Bengal, India.
Around 100 close contacts are being monitored in the South Asian country.
“Initial symptoms may include fever, headaches, muscle pain, vomiting and sore throat. In some people, these may be followed by drowsiness, altered consciousness, and pneumonia… To date, no drugs or vaccines have been approved to treat the disease.”
NO DRUGS OR VACCINES
The symptoms include flu, but could also lead to swelling in the brain or encephalitis and meningitis acquired by eating horsemeat and having interaction with a sick person, the DOH said.
Initial symptoms may include fever, headaches, muscle pain, vomiting and sore throat. In some people, these may be followed by drowsiness, altered consciousness, and pneumonia.
Encephalitis, a sometimes-fatal condition that causes inflammation of the brain, may occur in severe cases.
To date, no drugs or vaccines have been approved to treat the disease.
While human infections can arise through direct contact with an infected animal and their secretions, many infections result from the consumption of fruits or fruit products (such as raw or partially fermented date palm juice) contaminated with the poo, urine or saliva of infected fruit bats. Date palm juice is often known as Khejur Juice when raw and as Tari or Khajuri Tadi when fermented, according to a blog of the UK Health Security Agency.
Person-to-person spread is possible through close contact with an infected person or their body fluids. This has been documented in Bangladesh and India, most commonly among family members and close contacts caring for infected patients. Those with respiratory symptoms may pose a transmission risk, UKHSA said.
The incubation period (the time between becoming infected and symptoms appearing) is typically 4 to 21 days, though longer periods have occasionally been observed.
Aside from flu-like illnesses, the most serious complication is encephalitis (inflammation of the brain) or meningitis, which typically develops 3 to 21 days after the initial illness begins. This is the hallmark of Nipah infection and is associated with a very high mortality rate.
It is estimated that between 40 and 75% of people infected with Nipah virus will die. Some survivors may be left with lasting neurological difficulties, including persistent seizures and personality changes. In rare cases, the virus can reactivate months or even years after the initial infection.
ON TIGHT WATCH
Thailand has started screening passengers at three airports that receive flights from West Bengal. Nepal has also begun screening arrivals at Kathmandu airport and other land border points with India.
On Sunday, Thailand started screening passengers at three international airports in Bangkok and Phuket that receive flights from West Bengal. Passengers from these flights have been asked to make health declarations. The parks and wildlife department has also implemented stricter screenings in natural tourist attractions.
Jurai Wongswasdi, spokeswoman for the Department for Disease Control, told BBC Thai authorities are “fairly confident” about guarding against an outbreak in Thailand.
Nepal, too, has begun screening people arriving through the airport in Kathmandu and other land border points with India.
Meanwhile, health authorities in Taiwan have proposed to list the Nipah virus as a “Category 5 disease.” Under the island’s system, diseases classified as Category 5 are emerging or rare infections with major public health risks that require immediate reporting and special control measures.
The WHO has described Nipah in its top ten priority diseases, along with pathogens like Covid-19 and Zika, because of its potential to trigger an epidemic.
MISPLACED CONFIDENCE
Since the Philippines has had Nipah virus in Mindanao in 2014 and contained it then, the country is now more prepared to deal with it, said the Department of Health.
The virus is not new to the Philippines, healthspokesman Albert Domingo told ABSCBN. “Sa Sultan Kudarat. Ang nakita natin doon is yung mga tao na nahawa ay kumain ng laman ng kabayo. So kaya siya tinawag na zoonotic at tumatawid siya mula sa isang hayo papunta sa tao.”
Domingo reminded people to make sure that when consuming meat, this must be well cooked and sourced only from accredited suppliers by the National Meat Inspection Service.
The DOH also advised the people to avoid getting near bats or other sick animals. The virus can contaminate even pets like dogs, cats, pigs, sheep, goats and horses.
DOH added that they are in close coordination with the Bureau of Quarantine at the Ninoy Aquino International Airport and other major airports and seaports. “There is no need to raise the alert, just close monitoring.”
An outbreak of the deadly Nipah virus in India’s West Bengal state has sparked concern in parts of Asia, with some tightening screening measures at airports. Two cases have been confirmed in West Bengal since December, reportedly in healthcare workers. Some 196 people who were in contact with them have been traced and tested negative for the virus, India’s health ministry says.
People who contract the virus show a wide range of symptoms, or sometimes, none at all.
PAST OUTBREAKS
The first recognized Nipah outbreak was in 1998 among pig farmers in Malaysia and later spread to neighboring Singapore. The virus was named after the village where it was first discovered. More than 100 people died and a million pigs culled in an effort to contain the virus. It also resulted in significant economic losses for farmers and those in the livestock trade.
Bangladesh has borne the brunt in recent years, with more than 100 people dying of Nipah since 2001.
The virus has also been detected in India. Outbreaks were reported in West Bengal in 2001 and 2007.
More recently, the southern state of Kerala has been a Nipah hotspot. In 2018, 19 cases were reported of which 17 were fatal, and in 2023, two out of six confirmed cases later died.
India’s health ministry said that following confirmation of the cases in West Bengal, contacts of the infected individuals were “identified, traced, monitored, and tested” – and had been found to be asymptomatic.
“The situation is under constant monitoring, and all necessary public health measures are in place,” the ministry said.
Human outbreaks of Nipah virus have only been identified in South and South-East Asia, primarily in rural or semi-rural locations. Countries with previously reported outbreaks include:
• Bangladesh (where cases have occurred almost annually since 2001)
• India (including outbreaks in Kerala in Southern India since 2018, and a current outbreak in West Bengal)
• Malaysia
• The Philippines (in 2023)
• Singapore
Treatment is limited to intensive supportive care for those with severe infections.
PREVENTION, CAUTION
For those travelling to endemic areas, prevention focuses on avoiding exposure:
• avoid contact with bats and their environments, and sick animals
• don’t consume raw or partially fermented date palm sap – if consuming date palm juice, ensure it has been boiled first
• wash all fruit thoroughly with clean water and peel before eating; avoid consuming fruit found on the ground or fruit that appears to have been partially eaten by animals
• wear protective clothing and gloves when handling sick animals and during slaughter and culling procedures
• practice good hand hygiene, particularly after caring for or visiting sick people
• avoid close, unprotected contact with anyone infected with Nipah virus, including contact with their blood or body fluids
In healthcare settings, strict infection prevention and control measures are essential, including contact, droplet and airborne precautions for both suspected and confirmed patients.
Under DoH guidelines, surveillance measures include identification of high-risk areas, event and wildlife-based surveillance and screening of passengers for possible symptoms at points of entry. Domingo emphasized the urgency of correctly filling out e-travel forms especially for those arriving in the country.
With mechanisms from the recent pandemic remaining relatively fresh, especially for those deeply impacted by it, health experts say that panic should be the last thing on everyone’s minds.
Instead, the public should understand that every health event is about preparedness, that means knowing how it spreads, its symptoms and how prevention works are what will actually save lives even before an outbreak reaches communities.