6 new coronaviruses discovered in bats but no evidence of risk to human health, say experts
Scientists have discovered six new coronaviruses in bats, the same family of viruses as the one that causes COVID-19. However, according to the research team from the Smithsonian's Global Health Program, the newly discovered coronaviruses are not closely related to SARS-CoV-2, the coronavirus that causes COVID-19, or Severe Acute Respiratory Syndrome (SARS), or the Middle East Respiratory Syndrome (MERS).
The coronaviruses were found in bats in Myanmar, the first time these viruses have been detected anywhere in the world, say experts. While there is currently no evidence that these novel coronaviruses pose a risk to human health, the findings take on new relevance as the world grapples with the ongoing pandemic. Future studies will evaluate the potential for transmission across species to better understand the risks to human health, say researchers.
The researchers explain that viral pandemics are a reminder of how closely human health is connected to the health of wildlife and the environment. They emphasize that globally, humans are interacting with wildlife with increasing frequency. Accordingly, the more scientists understand about these viruses in animals - what allows them to mutate and how they spread to other species - the better they can reduce their pandemic potential. Many coronaviruses may not pose a risk to people, but when experts identify these diseases early on in animals, at the source, they have a valuable opportunity to investigate the potential threat. Vigilant surveillance, research, and education are the best tools we have to prevent pandemics before they occur, says the team.
“We have been saying within the medical community, ‘an epidemic is coming, it’s coming soon, it’s likely to be one of these three or four viral families, it has the potential to kill a lot of people.' Until it really touches people, it’s hard to recognize how connected we are. And as long as something’s happening across an ocean and far away, sometimes it’s hard to really feel the relevance of it. People now realize that we’re more connected than we think we are,” says Suzan Murray, director of the Smithsonian's Global Health Program and co-author of the study, in a statement.
Murray adds, “When people look at the COVID-19 response right now they’re saying, ‘Oh my goodness, too bad we weren’t prepared.’ This is what it looks like when we were pretty well prepared.”
Why bats? Coronaviruses have caused widespread disease in humans, and experts estimate that thousands of coronaviruses - many of which have yet to be discovered - are present in bats. “The 2002–2003 SARS epidemic, the emergence of MERS in people in 2012, and the ongoing COVID-19 pandemic has prompted substantial interest in detecting coronaviruses of bat origin due to public health concern and their pandemic potential,” says the team.
Accordingly, the findings will help understand the diversity of coronaviruses in bats and inform global efforts to detect, prevent and respond to infectious diseases that may threaten public health, particularly in light of the ongoing COVID-19 pandemic, say experts.
The study
Researchers detected these new viruses while conducting biosurveillance of animals and people to better understand the circumstances for disease spillover as part of the PREDICT project. PREDICT is an initiative funded by the US. Agency for International Development (USAID). It supports the global discovery and surveillance of pathogens that have the potential to spread from animals to humans.
“Emerging infectious diseases (EIDs) are capable of causing debilitating health effects and financial instability. An estimated 60–75% of EIDs are comprised of zoonotic diseases; of these, more than 70% have purportedly originated in wildlife species,” says the study published in PLOS One.
The team in Myanmar comprised scientists from the Smithsonian; the University of California, Davis; Myanmar's Ministry of Agriculture, Livestock, and Irrigation; Myanmar's Ministry of Health and Sports; and Myanmar's Ministry of Natural Resources and Environmental Conservation.
The researchers focused their research on sites in Myanmar where humans are more likely to come into close contact with local wildlife due to changes in land use and development.
Between May 2016 and August 2018, sample and data collection occurred at three selected sites in Myanmar: Northern District in Yangon Region, near Hlawga National Park, Hpa-An in Kayin state, and Shwebo of Sagaing region. “These sites were targeted as potential high-risk human-animal interfaces due to land-use change increasing human proximity to wildlife and potential human exposures through livelihood, recreational, commercial, and religious or cultural activities. Two of these sites also featured popular cave systems where people were routinely exposed to bats through guano harvesting, religious practices, and ecotourism,” say experts.
From May 2016 to August 2018, they collected over 750 saliva and fecal samples from bats in these areas. Researchers tested and compared the samples to known coronaviruses and identified six new coronaviruses. The team also detected a coronavirus that had been found elsewhere in Southeast Asia, but never before in Myanmar.
“Viral detection, discovery, and surveillance activities were undertaken in Myanmar to identify viruses in animals at high-risk contact interfaces with people. Free-ranging bats were captured, and rectal and oral swabs and guano samples collected for coronaviral screening using broadly reactive consensus conventional polymerase chain reaction,” says the study. It adds, “Sequences from positives were compared to known coronaviruses. Three novel alpha coronaviruses, three novel beta coronaviruses, and one known alphacoronavirus previously identified in other southeast Asian countries were detected for the first time in bats in Myanmar.”
According to the experts, the findings underscore the importance of surveillance for zoonotic diseases as they occur in wildlife. “Given the essential ecosystem services provided by bats, public health efforts should advocate for preventative measures to protect people against disease transmission while enabling human communities and bats to coexist on a shared landscape,” recommends the team.