Nipah Virus Disease - Fact Sheet

What is Nipah virus disease?

Nipah virus is a disease that can affect both animals and humans.

The virus was first identified in swine, and people who worked with them. It has subsequently been identified in dogs, cats, horses, and goats.

The fruit bat, also know as the "flying fox" is the natural host for the virus. The bat also hosts the Hendra virus.

Is Nipah virus disease a risk to human health?

The risk to Canadians is considered to be low as there are no species of fruit bats in Canada. However, people working with swine in Southeast Asia should be aware of the risk.

In humans, the symptoms of Nipah virus resemble influenza and can include:

  • fever;
  • severe headaches;
  • muscle pain;
  • dizziness; and
  • vomiting.

More serious symptoms affecting the central nervous system include coma, seizures and the inability to breathe. The disease may progress to encephalitis (inflammation of the brain) or meningitis, with a 40 per cent fatality rate.

What are the clinical signs of Nipah virus disease in swine?

Nipah virus affects both the nervous system and the respiratory system. The clinical signs in swine include:

  • fever;
  • a loud, barking cough;
  • respiratory distress (open mouthed breathing, rapid and laboured respiration);
  • trembling;
  • muscle spasms;
  • weakness in the hind limbs; and
  • a lack of coordination.

In sows and boars particularly, the following signs can be observed:

  • agitation;
  • head pressing;
  • increased salivation and nasal discharge;
  • seizures; and
  • sudden death.

Abortions have been reported in affected sows.

The illness can affect 100 per cent of the herd, but mortality is generally less than five per cent, except in piglets, where it is higher.

Where is Nipah virus found?

It was first described in Malaysia in 1999, resulting in illness in swine and a number of associated human fatalities in people who worked closely with the sick pigs. Since 1999, there have been additional human outbreaks in Singapore, Bangladesh and India; the Singapore outbreak is the only one linked to swine exposure.

The virus is likely endemic in Southeast Asia, which is the natural habitat of the fruit bat.

The Nipah virus has never been found in Canada.

How is Nipah virus transmitted and spread?

There is uncertainty about how the virus is spread in humans and pigs.

The illness and mortality in humans was initially associated with exposure to the excretions and secretions of infected pigs; however more recent outbreaks have occurred without animal illness.

How is Nipah virus disease diagnosed?

Testing of lung and brain samples confirms diagnosis in pigs.

Because Nipah virus is a zoonotic disease, samples must be collected, handled and transported with appropriate biosecurity precautions.

How is Nipah virus disease treated?

There is no treatment or preventative vaccine currently available.

What is done to protect Canadian livestock from the Nipah virus disease?

The Canadian Food Inspection Agency (CFIA) imposes strict regulations on the import of animals and animal products from countries where Nipah virus is known to occur. These regulations are enforced through port-of-entry inspections done either by the Canada Border Services Agency or the CFIA.

Nipah virus is a "reportable disease" under the Health of Animals Act. This means that all suspected cases must be reported to the CFIA for immediate investigation by inspectors.

How would the CFIA respond to an outbreak of Nipah virus disease?

Canada's emergency response strategy in the event of an outbreak of Nipah virus would be to:

  • eradicate the disease; and
  • re-establish Canada's disease-free status as quickly as possible.

In an effort to eradicate the Nipah virus, the CFIA would use its "stamping out" policy, which includes:

  • the humane destruction of all infected and exposed animals;
  • surveillance and tracing of potentially infected or exposed animals;
  • strict quarantine and animal movement controls to prevent spread;
  • strict decontamination of infected premises; and
  • zoning to define infected and disease-free areas.

Owners whose animals are ordered destroyed may be eligible for compensation.

Canada's National Center for Foreign Animal Disease in Winnipeg is part of an international collaborative effort to study Nipah virus and is working on the development of a rapid diagnostic capability.

Additional information