Habitat loss may have triggered Nipah outbreak: WHO report
According to report by World Health Organisation (WHO), human-triggered factors like habitat loss due to deforestation and climate change set off infectious outbreaks such as recent Nipah cases in Kerala. Due to habitat destruction by human activity, flying fox (fruit bat), a natural host of Nipah virus get stressed and hungry, which weakens its immune system, increasing virus load. It results in lot of virus spilling from urine and saliva of bats.
Findings of Study
There is strong evidence that emergence of bat-related viral infections can be attributed to loss of animal’s natural habitats. Reproductive and nutritional stress are potential role players in Nipah and Hendra (Nipah equivalent in Australia) viruses spillover. Nutritional stress is mainly due to loss of food resources which is direct consequence of habitat loss and climate change brings bats closer to urban areas.
Forest fragmentation and hunting bats for food also bring them closer to humans and is often an important cause of disease transmission. It can be seen from rapid urbanisation of bat-rich rainforests contributed to the emergence of Nipah virus in Malaysia.
Nipah virus (NiV) infection is zoonotic disease (disease transmitted to humans from animals) that causes severe disease in both animals and humans. The organism which causes Nipah Virus encephalitis is RNA or Ribonucleic acid virus of family Paramyxoviridae, genus Henipavirus, and is closely related to Hendra virus.
Fruit bats or flying foxes of Pteropodidae Family, Pteropus genus are natural host of Nipah virus. The virus is present in bat urine and potentially, bat faeces, saliva, and birthing fluids. It was first identified in 1999 during outbreak among pig farmers in Malaysia and Singapore. It gets its name from Sungai Nipah, a Malaysian village, where pig farmers became ill with encephalitis.