Influenza D & Canine Coronavirus: Next Pandemic Threats?

Infectious disease experts are raising concerns about two animal-borne viruses – influenza D and canine coronavirus – that have the potential to become significant public health threats. While currently circulating largely undetected, these pathogens are exhibiting characteristics that suggest they could adapt to more easily spread among humans, potentially triggering outbreaks or even pandemics.

The warning comes from a research collaboration involving scientists from the universities of Texas, Florida, Kentucky, and Ohio State University. Their review of existing literature, published in the January issue of Emerging Infectious Diseases, highlights a critical gap in surveillance and diagnostics for these viruses. This lack of preparedness, they argue, creates a dangerous blind spot as both viruses demonstrate an ability to evolve.

“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,” explained Dr. John Lednicky, a research professor at the University of Florida in Gainesville, in a news release. “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.”

Influenza D: A Threat Emerging from Livestock

Influenza D virus was first discovered in 2011 and has since been identified in a wide range of livestock and wildlife, including pigs, cows, poultry, deer, giraffes, and even kangaroos. It is currently believed to contribute to bovine respiratory disease, a condition that costs the U.S. Cattle industry approximately $1 billion annually.

However, the virus is no longer confined to animal populations. Studies conducted in Colorado and Florida have revealed that up to 97% of workers who regularly interact with cattle herds carry antibodies for influenza D, indicating prior exposure. Importantly, these human infections have, to date, been subclinical – meaning they haven’t caused noticeable symptoms of illness. Despite this, scientists emphasize that influenza D possesses the hallmarks of a virus capable of rapid evolution.

Recent developments are particularly concerning. A specific strain of influenza D identified in China has already demonstrated the ability to move from person to person, raising the stakes for potential widespread transmission.

Canine Coronavirus: A Respiratory Risk Beyond Dogs

Canine coronavirus (CCoV) presents a different, yet equally concerning, scenario. While traditionally associated with gastrointestinal issues in dogs, new strains are emerging that appear to target the human respiratory system.

Cases of CCoV have been documented in several countries, including Malaysia, Thailand, Vietnam, and even Arkansas. In some instances in Southeast Asia, the virus has been linked to patients hospitalized with pneumonia. The true extent of human infection remains unknown, however, as hospitals do not routinely test for canine coronavirus.

Unlike SARS-CoV-2, the virus responsible for COVID-19, canine coronavirus typically causes stomach issues in dogs. The emergence of strains affecting the human respiratory system represents a significant shift in the virus’s behavior and potential impact.

The Need for Enhanced Surveillance and Preparedness

Researchers are united in their call for increased surveillance, improved diagnostics, and proactive countermeasures to address these emerging threats. The lack of readily available diagnostic tests and vaccines is a major concern, hindering efforts to track the spread of these viruses and develop effective prevention strategies.

Shahbaz Salehi, MD, MPH, MSHIA, director of infection prevention and control—employee health at Foothill Regional Medical Center in Tustin, California, suggests a key step forward would be a unified, real-time information exchange platform involving hospitals and clinics. “This platform would allow health care facilities to share critical operational data such as respiratory patient census, ICU capacity, staffing constraints, PPE and supply availability, and testing capability,” he stated.

Salehi emphasizes that voluntary participation in such systems has proven insufficient, leading to fragmented data and delayed situational awareness. He advocates for a mandate requiring hospitals to participate, similar to existing reporting obligations, to enable earlier detection of emerging respiratory threats and improve resource coordination.

The limited data currently available are enough to warrant serious attention, researchers conclude. Investing in better surveillance systems, developing more accurate diagnostic tests, and preparing for potential outbreaks are crucial steps in mitigating the risk posed by influenza D and canine coronavirus. The lessons learned from recent pandemics underscore the importance of proactive preparation in the face of emerging infectious diseases.