The recent outbreak of Nipah virus (NiV) in the northern region of Bangladesh has created panic like previous years and drawn much attention of media. The total death of 8 people this year has been a significant cause for concern. As there is no vaccine or specific drug to treat it, precaution is the best way to cope.

Nipah virus causes severe illness in both human and animal characterised by inflammation of the brain (called encephalitis) or respiratory diseases.

Nipah virus can be transmitted to humans from animals specially from bat, and can also be transmitted directly from human-to-human.

In the Bangladesh outbreaks, consumption of fruits or fruit products (e.g. raw date palm juice) contaminated with urine or saliva from infected fruit bats was the most likely source of infection. During the later outbreaks in Bangladesh, Nipah virus spread directly from human-to-human through close contact with people's secretion and excretion. Half of the reported cases in Bangladesh between 2001 and 2008 were due to human-to-human transmission.

Infected people may be symptomless or initially develop influenza-like symptoms �" fever, headache, myalgia (muscle pain), vomiting and sore throat. This can be followed by dizziness, drowsiness, altered consciousness and neurological signs that indicate acute encephalitis. Some people can also experience atypical pneumonia and severe breathing problems, including acute respiratory distress. Encephalitis and convulsion occur in severe cases, progressing to coma within 24 to 48 hours.

Most people who survive acute encephalitis make a full recovery, but around 20% are left with residual neurological consequences such as persistent convulsions and personality changes. The case fatality rate is estimated at 40% to 75%; however, this rate can vary by outbreak depending on local capabilities for surveillance investigations.

Intensive supportive care with treatment of symptoms is the main approach to managing the infections in people. Prevention is the best way to fight Nipah virus infection.

Here are some messages to help prevent the transmission of the virus:

-Reducing the risk of bat-to-human transmission: Efforts to prevent transmission should first focus on decreasing bat access to date palm sap. Freshly collected date palm juice should also be boiled and fruits should be thoroughly washed and peeled before consumption.

-Reducing the risk of human-to-human transmission: Close physical contact with Nipah virus-infected people should be avoided. Gloves and protective equipment should be worn when taking care of ill people. Regular hand washing should be carried out after caring for or visiting sick people.

-Reducing the risk of animal-to-human transmission: Gloves and other protective clothing should be worn while handling sick animals or their tissues, and during slaughtering and culling procedures.

-Controlling infection in health-care settings: Health-care workers caring for patients with suspected or confirmed Nipah virus infection or handling specimens from them, should implement standard infection control precautions. Samples taken from people and animals with suspected Nipah virus infection should be handled by trained staff working in suitably equipped laboratories.

Source: World Health Organisation