Scientists say these two viruses may become the next public health threats

Small mixed-breed dog with tan, white and gray fur looks alertly upward while sitting in green grass.
Researchers warn that canine coronavirus, which has been linked to human respiratory illness in Southeast Asia, and influenza D, commonly found in cows, deserve closer monitoring to prevent future human outbreaks. Credit: Adobe Stock.

By Jill Pease

Dr. Lednicky
John Lednicky, Ph.D.

Two emerging pathogens with animal origins — influenza D virus and canine coronavirus — have so far been quietly flying under the radar, but researchers warn conditions are ripe for the viruses to spread more widely among humans.

If surveillance and diagnostics continue to lag, influenza D virus and canine coronavirus have real potential to trigger outbreaks, a team of infectious disease experts and authors write in an article in the January issue of Emerging Infectious Diseases, a journal of the Centers for Disease Control and Prevention.

“Our review of the literature indicates these two viruses pose respiratory disease threats to humans, yet little has been done to respond to or prevent infection from these viruses,” said co-author John Lednicky, Ph.D., a research professor in the Department of Environmental and Global Health at the University of Florida’s College of Public Health and Health Professions. “If these viruses evolve the capacity to easily transmit person to person, they may be able to cause epidemics or pandemics since most people won’t have immunity to them.”

Since its discovery in 2011, influenza D virus has been associated with infections in pigs and cows, but it has also been found in many other livestock and wildlife species, including poultry, deer, giraffes and kangaroos. Influenza D virus is believed to contribute to bovine respiratory disease, estimated to cost the U.S. cattle industry $1 billion a year.

The authors’ previous studies of cattle workers in Colorado and Florida found that up to 97% of people working with herds carry influenza D virus antibodies, suggesting the workers had been exposed to the virus. So far, these infections are known to be subclinical, meaning they have not caused symptoms of illness. However, scientists say influenza D virus bears the hallmarks of a virus primed to rapidly evolve. Indeed, a strain of influenza D recently isolated in China has developed the capacity for human-to-human transmission.

“So far, influenza D virus has not been associated with serious infections in humans,” said Lednicky, a member of UF’s Emerging Pathogens Institute. “However, canine coronavirus has, but diagnostic tests are not routinely performed for the virus so the extent at which the virus affects the population at large is not known.”

Read the full story in the UF Health newsroom.