Bats cannot directly infect humans with Covid-19: Scientists
According to scientists, Sars-Cov-2 may have diverged from the closest coronavirus found in bats called RaTG13, about 40 to 70 years ago, indicating that the bat virus cannot directly infect humans.
Sixty-four scientists have said bats do not spread Covid-19 after reports of people requesting local authorities to clear trees over a fear of the colonies the winged mammals host.
The chiropterologists issuing the statement said they came together after reports of public requesting removal of bats, destroying bat roosts, bursting crackers or smoking them out and sealing crevices where bats and their pups roost came to them from various parts in India.
They argued in their statement on Friday that Sars-Cov-2 may have diverged from the closest coronavirus found in bats called RaTG13, about 40 to 70 years ago indicating that the bat virus cannot directly infect humans.
“The coronavirus found in one species of bat was found to be the closest match to the novel Sars-Cov-2. However, studies show that it cannot bind efficiently to receptors in the human lungs. This suggests that the virus may have evolved in an intermediate host. At the moment, a lot of evidence points towards pangolins as being the intermediate host. However, there is, as yet, no scientific consensus,” Rohit Chakravarty, a research scholar at Berlin’s Leibniz Institute for Zoo and Wildlife Research, said.
“This should not become a reason to demonise pangolins which are currently the world’s most trafficked animals. Instead, we must push for the increased protection of these rare and elusive animals,” Chakravarty said.
A recent study by Indian Council of Medical Research (ICMR) had found coronaviruses in two bat species in Indian but they are not the same as Sars-Cov-2 and cannot cause Covid-19, the scientists said.
The driving factor behind viruses jumping over from animals to humans is encroachment and destruction of wildlife habitats.
“Human activities and encroaching upon wildlife habitats puts us at risk of encountering new viruses. These viruses may come from any wildlife species and not necessarily just bats. Thus, we need to modify human practices to prevent the emergence of new pathogens,” Arinjay Banerjee, a postdoctoral researcher at McMaster University, Canada, who studies bat viruses.
Banerjee was a part of the team that isolated the Covid-19 virus.
Changing human-wildlife interface, global wildlife trade and industrial livestock farming are all suspects in causing zoonotic disease outbreaks like Covid-19, they underlined.
Six myth busters from the team of bat experts:
• The exact origin of Sars-Cov-2 or its precursor is not known yet
• Scientists strongly suggest that it is highly unlikely for Sars-like viruses to jump directly from bats to humans. Also, there is no evidence of humans contracting coronavirus or any such viruses through the excreta of bats.
• ICMR report on the discovery of bat coronaviruses (BtCoV) in two species of South Asian bats poses no known health hazard.
• Information on the current, and past zoonotic disease outbreaks suggest that global wildlife trade and/or large-scale industrial livestock farming play an important role in such events.
• Killing bats and other wild animals, or evicting them from their roosts in retaliation is counterproductive and will not solve any problems.
• Bats pollinate the flowers of some mangroves, and many other commercially and culturally important plants.
• Insect-eating bats are voracious eaters of pest insects in rice, corn, cotton and potentially, tea farms. Therefore, bats benefit ecological and human health and provide intangible economic benefits.
• South Asian countries should strengthen the legal framework to protect bats in view of their ecosystem services and their slow breeding capacity.