The Department of Disease Control has confirmed that no Nipah virus infections have been detected in humans in Thailand and the department has had a strict monitoring system in place for a long time, under the “One Health” concept.
Dr Jurai Wongsawat, spokesperson for the department, said that the system entails the monitoring of animal and human health, especially as regards meningitis.
She also said that the Livestock Development Department and the Department of National Parks, Wildlife and Plant Conservation, as well as the Forest Department, have also been watching out for the Nipah virus.
Nipah is a deadly virus with no vaccine or cure and is considered a high-risk pathogen by the World Health Organisation. The virus is a zoonotic pathogen, which means that it can be transmitted from animals to humans and from person to person.
The primary natural carriers are fruit bats (Pteropus species, also commonly known ‘flying foxes’).
Humans can become infected through direct contact with the infected bats or other animals or by consuming food contaminated with bat saliva, urine or faeces.
India is currently trying to contain a Nipah virus (NiV) outbreak in the eastern state of West Bengal, where five cases have been confirmed, including among doctors and nurses.
Nearly 100 people have been asked to quarantine at home and infected patients are being treated in hospitals in and around the state capital of Kolkata.
Dr Jurai explained that the Nipah virus cannot easily spread from animals to humans, or from humans to humans, unless they are in very close contact, such as between patients and medical personnel. Infections from animals to humans is often through consumption of contaminated food.
NiV infection most often begins with non-specific symptoms, making early detection difficult.
According to the US Centres for Disease Control and Prevention (CDC), the incubation period is generally believed to range from four to 21 days, though longer periods between exposure and illness have been reported in rare cases.
Patients typically develop a sudden flu-like illness, marked by fever, headache, muscle pain and fatigue. In some cases, respiratory symptoms, such as a cough, shortness of breath or pneumonia also occur, although the timing and severity of these symptoms can vary widely.
The most serious and defining complication of Nipah infection is inflammation of the brain, known as encephalitis.
Neurological symptoms, including confusion, altered consciousness, seizures or coma, usually appear several days to weeks after the initial onset of illness. Some patients may also develop meningitis, an inflammation of the membranes around the brain and spinal cord.
The Nipah virus is associated with a high mortality rate, with levels reported between 40% and 75%, depending on the outbreak and viral strain involved.
Dr. Jurai said that Thailand has not yet introduced any special measures to screen people arriving from India, because the outbreak of the disease in India is still limited to specific areas and very sick patients would be too weak to travel anyway.
She has also stressed to members of the public that there is no cause for panic, but there is a need to be aware of the disease.
If it is necessary to travel to parts of India where an outbreak is being reported, extreme caution needs to be exercised, such as avoidance of direct contact with the patients, the consumption of known-safe food and the wearing of face masks.
