DHAKA

Health experts in Bangladesh have reported a fresh outbreak of the Nipah virus, with 10 deaths in the past few weeks. If infected you have a high chance of dying.

“The fatality rate is an astounding 77 percent,” ASM Alamgir, a virologist at the Institute of Epidemiology, Disease Control and Research (IEDCR), told IRIN.

Since the deadly pathogen appeared in Bangladesh 12 years ago, 188 cases and 146 deaths have been reported; including 12 infections and 10 deaths so far in 2013. The virus is zoonotic, meaning it can be transmitted between animals and humans.

Infection is caused by the consumption of the raw sap of a date palm tree which has been contaminated with urine or saliva from infected fruit bats. When the sap is consumed, the virus infects the human body. Once infected, the patient can spread the virus to other people through physical contact, health experts say.

Winter (December to early February) is the traditional date palm sap gathering season in Bangladesh and the raw sap is a popular drink in rural areas. The outbreak coincides with this season, appearing between December and May.

Traditionally outbreaks have taken place in a group of 10 districts (Meherpur, Noagoan, Rajbari, Faridpur, Tangail, Thakurgaon, Kushtia, Manikgonj, Rajshahi, and Lalmonirhat) known as the “Nipah belt”. However, Dhaka, the Bangladeshi capital, reported its first victim in January.

“Although the sap was brought from Mymensingh [District], it was consumed in Dhaka. This is the first case of a Nipah-related death in the city,” said Alamgir.

The most recent death was of an 11-month-old baby in the port city of Chittagong on 4 February.

Government response

With no treatment or vaccine available for either people or animals, prevention and public awareness are key, health experts say.

“The only effective way of preventing the Nipah outbreaks is to stop people from drinking raw date palm sap. Awareness remains quite low, and as this is a popular drink the risk is constant,” said Ferdousi Begum, a specialist and assistant professor at Dhaka Medical College.

“To prevent this practice, the government has undertaken awareness-raising campaigns through newspaper advertisements, talk shows and discussions on local TV,” said Alamgir. “We have to observe the entire season to understand the severity of the current outbreak,” he said, noting there were currently five monitoring centres (Rangpur, Rajshahi, Bogura, Faridpur, Rajbari) within the Nipah belt, as well as two more in Chittagong and Sylhet, allowing any diagnosed cases to be quickly reported back to Dhaka.

According to World Health Organization, although the Nipah virus has caused only a few outbreaks, it can infect a wide range of animals and causes severe illness (characterized by inflammation of the brain - encephalitis - or respiratory diseases) and death in people, making it a public health concern.

The Nipah virus was first identified in 1999 during an outbreak among pig farmers in Malaysia. Since then, there have been more than 12 outbreaks, all in South Asia.

Research on a new vaccine, based on trials with monkeys, is promising, US and Canadian researchers report.

ao/ds/cb