Selected airports in Asia have begun screening passengers arriving from India as officials respond to new Nipah virus detections in West Bengal. Measures are active at major hubs in Thailand and Singapore, with checks also reported at Kathmandu airport in Nepal and at land border crossings with India. Health authorities in New Zealand say they are monitoring developments while maintaining routine protocols at the border. “At this stage, the World Health Organisation considers the risk of international disease spread to be low,” they said in a joint statement to the Herald.
Where screening is occurring
The targeted measures are designed to support existing national surveillance systems rather than signal a change in global risk level. Border agencies are acting under their respective public‑health and civil‑aviation mandates, which were substantially strengthened after Covid‑19.
- Thailand: targeted screening at Bangkok and Phuket international airports for passengers arriving from India, overseen by airport health control units.
- Singapore: screening at Changi Airport focused on incoming travelers from India, operating within the city‑state’s communicable‑disease framework.
- Nepal: screening at Kathmandu’s international airport and at land border points with India, with health desks checking arrivals on key land routes.
- New Zealand: no Nipah-specific screening at the border; routine processes for unwell arrivals remain in place.
New Zealand’s stance: monitoring without Nipah‑specific checks
Officials emphasize that routine systems for managing ill travelers continue to operate at international airports. “The Ministry of Health is monitoring the spread of Nipah virus overseas and provides updates to the National Public Health Service to inform its screening and detection work.”
They add: “There are systems in place to ensure any traveller who arrives in New Zealand unwell is checked and managed appropriately to the situation.” Those processes sit under New Zealand’s notifiable-disease and border-health regulations, which give health officers powers to assess and isolate unwell arrivals where required.
Epidemiologist Michael Baker assessed the likelihood of local impact as limited. “In New Zealand, we really shouldn’t be at all concerned about this infection because it’s got animal reservoirs,” the University of Otago professor said, noting that the reservoir species are not present in Aotearoa and that any imported case would still require close contact to spread.
How Nipah spreads and why reservoir ecology matters
Baker underscored the role of fruit bats in spillover events. “Fruit bats – they can feed on fruit, so they can contaminate the environment. That’s also the result in human infections.
“They’re direct infections. We call that a spillover infection from an animal reservoir … infection from animals.” In previous outbreaks in South and Southeast Asia, that has included infections linked to contaminated date‑palm sap and close contact with infected pigs, as well as limited person‑to‑person transmission in household and hospital settings.
- Primary reservoir: fruit bats (flying foxes), with spillover to humans and, at times, domestic animals.
- Transmission settings documented in past outbreaks: exposure to bat-contaminated fruit or environments; limited person‑to‑person spread in close-contact settings; occasional amplification in healthcare environments without strict infection control.
- Clinical spectrum: from asymptomatic infection to severe respiratory disease and encephalitis; severe illness can strain intensive care capacity where cases cluster.
- Medical countermeasures: no widely available licensed human vaccine; care is supportive; public‑health measures focus on early case detection, isolation in clinical settings, and contact tracing.
- Technical guidance: global best practice is framed within the One Health approach; see the World Health Organization’s Nipah resources and CDC technical pages for pathogen profiles and surveillance considerations.
External resources: World Health Organization | CDC
Why pandemic potential is judged low at this stage
Nipah has caused severe local outbreaks, but experts note that efficient sustained human‑to‑human transmission has not been a dominant feature. The virus carries a high case‑fatality rate – estimates in the literature range from about 45 to 75 per cent – yet chains of transmission have typically been self‑limiting once infection‑control measures are in place.
“There are hundreds of zoonotic infections in the world. Most pandemics start as spillover infections from animal reservoirs – that’s the main source of pandemics.
“But most of the time, humans are what we call a dead-end host. So we get infected and, if it’s a new zoonotic infection, there’s often a high fatality risk – but very few of them progress to easy human-to-human transmission.
“But I think the world is quite sensitised to these infections. It’s why we need to get on top of any new viral infection or any infection from animals that we haven’t seen before.
“Very few infections have great potential for transmission between people – and this one doesn’t at the moment.”
Border screening in the public‑health toolkit
For governments, border measures are as much about signalling and coordination as they are about detecting individual cases. Health ministries and aviation regulators use temporary screening to demonstrate vigilance, channel advice to travellers and stress‑test referral pathways under real‑world conditions.
- Purpose: visible precaution during periods of uncertainty, a channel for health messaging, and a way to triage symptomatic travelers for further assessment.
- Limitations: symptom‑based checks can miss infections in the incubation period or those with mild, non‑specific symptoms; airport screening performs best when paired with clinical surveillance and strong laboratory networks.
- Complementary measures: case finding in healthcare settings; rapid diagnostics; isolation and clinical management pathways; contact tracing and monitoring.
- Cross‑border coordination: information sharing between ministries of health and civil aviation authorities supports risk assessments and consistent traveler communications.
Policy status by jurisdiction
The current mix of measures reflects differing proximity to India, travel volumes and health‑system capacity, rather than divergent readings of the underlying science. All four jurisdictions continue to align their responses with World Health Organisation risk assessments and their own communicable‑disease laws.
| Jurisdiction | Current measure | Rationale | Notes |
|---|---|---|---|
| Thailand (Bangkok, Phuket) | Screening of passengers arriving from India | Precautionary response to detections in West Bengal | Focus on symptom checks and referral pathways |
| Singapore (Changi) | Screening for arrivals from India | Early identification of unwell travelers | Part of broader communicable‑disease surveillance |
| Nepal (Kathmandu; land borders) | Screening at airport and land crossings with India | Risk mitigation at high‑traffic points of entry | Supports triage and onward referral capacity |
| New Zealand | No Nipah‑specific screening at border | Risk judged low; routine systems in place | Monitoring updates through National Public Health Service |
Health system capacity and preparedness
Beyond the border, officials say the real test of readiness lies inside hospitals and laboratories. Governments are leaning on infrastructure expanded during the Covid‑19 pandemic, including genomic sequencing and high‑consequence infectious‑disease training for frontline staff.
- Surveillance: event‑based surveillance and clinician alerts help identify suspected cases early, especially among travelers from affected areas.
- Laboratories: biosafety‑level capacity and validated assays enable confirmatory testing and genomic characterization when needed.
- Healthcare workforce: training on high‑consequence pathogens supports rapid isolation, appropriate PPE use, and safe clinical management.
- Infection prevention and control: standard and transmission‑based precautions reduce the risk of nosocomial spread during evaluation and care.
- Risk communication: clear, non‑alarmist messaging sustains public trust while encouraging timely healthcare seeking for compatible illness.
Equity and movement across borders
Officials and experts stress that any targeted screening must be implemented in ways that avoid stigma and do not deter people from seeking care. That includes ensuring information is available in languages used by migrant workers and frequent cross‑border traders.
- Mobile and migrant populations may face barriers to care; inclusive communication and access to evaluation pathways are essential to reduce missed cases.
- Border communities and transport workers can be key partners in timely reporting and referral during targeted screening periods.
Travel and exposure context
Baker urged caution around wildlife interfaces in affected regions. “It’s yet another reason to avoid contact with bats.” Travellers are also advised to avoid consumption of raw date‑palm sap, steer clear of areas where fruit bats are feeding, and seek medical attention promptly if they develop fever or neurological symptoms after returning from affected areas.