It seems the outbreak of Nipah is re-emerging this year, as four people have died in the last 10 days in Rajshahi alone. Five more patients infected with Nipah Encephalitis were admitted to hospital and are in close observation, it is learnt.
All the deceased were infected by Nipah Virus, said Dr ASM Alamgir, a research consultant of World Health Organization (WHO).
Infected people from Nipah virus initially develop influenza like symptoms, such as fever, headaches, vomiting and sore throat. This can be followed by dizziness, drowsiness, altered consciousness, and neurological signs that indicate acute encephalitis, Rajshahi Medical College doctors said.
Some people can also experience atypical pneumonia and severe respiratory problems. Treatment is mostly symptomatic and supportive as the effect of antiviral drugs is not satisfactory and effective vaccine is yet to be developed.
Research from WHO shows that the first identification of Nipah virus as a cause of an outbreak of encephalitis was reported in 2001 in Meherpur district of Bangladesh. Since then, outbreaks of Nipah virus encephalitis have been reported almost every year in selected districts of Bangladesh.
The Nipah outbreaks have been identified in Rajbari and Faridpur (2004), Tangail (2005), Thakurgaon, Kushtia (2007), Manikganj and Rajbari (2008), Rangpur and Rajbari (2009), Faridpur, Rajbari and Madaripur (2010) and Lalmonirhat, Dinajpur, Rangpur and Comilla (2011) and Joypurhat, Rajshahi, Rajbari and Natore (2012).
Reported cases were mostly from the west and north-western regions of Bangladesh almost every year with high mortality and constituting a public health threat.
Dr Alamgir assures The Daily Observer that though four deaths have been reported and five have been infected with the virus, there is no chance that it will turn pandemic. But again, date palm juice has been prohibited in some selected countries where previous attacks were reported, he reminds.
Case fatality rate of Nipah virus infection ranges from 40-70 per cent although it has been as high as 100 per cent in some outbreaks. Many of the outbreaks were attributed to fruits partially eaten by fruit bats, and transmission of infection to humans.
Dr Alamgir said fruit bats drink from date palm sap at night. Their saliva mixes into the sap and stored in jar which is tied to the tree. He also mentions that during drinking, bats urinate into the jar which is another cause of spreading the infection.
In the absence of a vaccine, the only way to reduce infection in people is by raising awareness of the risk factors and educating people about the measures they can take to reduce exposure to the virus. Public health educational messages should focus on the followings, suggested Dr Alamgir.
" 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. He also suggests that the doctor and nurse should wear gloves as well.
" 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.