Potential Pandemics: Canine Coronavirus, Influenza D

Two animal-origin viruses – influenza D and canine coronavirus – are receiving increased attention from researchers who warn they pose potential, yet currently underappreciated, threats to human health. A recent review published in Emerging Infectious Diseases highlights the need for greater surveillance and preparedness to prevent possible future outbreaks.

Underrecognized Threats

Influenza D: A Growing Concern

Since its discovery in 2011, influenza D virus has been found in a variety of animals, including pigs, cows, poultry, deer, giraffes, and kangaroos. It’s believed to contribute to bovine respiratory disease, costing the US cattle industry an estimated $1 billion annually. Studies have shown that up to 97% of cattle workers in Colorado and Florida carry antibodies for the virus, indicating exposure, though infections have so far been asymptomatic.

Did You Know? A strain of influenza D virus recently isolated in China has demonstrated the capacity for human-to-human transmission.

Canine Coronavirus: Emerging Evidence of Spread

While canine coronavirus (CCoV) typically causes gastrointestinal illness in dogs, it has been linked to pneumonia hospitalizations in Southeast Asia. Researchers isolated a strain, named HuCCoV_Z19Haiti, from a medical team member after travel to Haiti in 2017, who experienced mild fever and malaise. A similar strain, CCoV-HuPn-2018, was later discovered in a hospitalized child in Malaysia.

Since 2021, CCoV-HuPn-2018 has been identified in people with respiratory illness in Thailand, Vietnam, and Arkansas, demonstrating its circulation across multiple continents. Diagnostic tests for canine coronavirus are not routinely performed, meaning the full extent of its impact on the population remains unknown.

Expert Insight: The limited data available on these viruses underscores the critical need for proactive monitoring and research. Without sufficient understanding of their epidemiology and clinical effects, we risk being unprepared for potential widespread transmission.

What Could Happen Next?

Researchers emphasize that if surveillance and diagnostic capabilities remain limited, both influenza D virus and canine coronavirus could trigger outbreaks. The viruses’ potential to evolve and gain efficient human-to-human transmissibility is a significant concern, particularly given that most people currently lack immunity. Improved virus monitoring, more reliable tests, and the potential development of treatments and vaccines are considered essential preventative measures.

Frequently Asked Questions

What is the difference between canine coronavirus and the virus that causes COVID-19?

Canine coronavirus is distinct from SARS-CoV-2, the virus responsible for COVID-19. While both are coronaviruses, they primarily affect different species and have different characteristics.

Have influenza D viruses caused serious illness in humans?

So far, influenza D virus has not been associated with serious infections in humans, though infections have been documented.

Where have cases of canine coronavirus in humans been identified?

Documented canine coronavirus infections in humans have been linked to pneumonia hospitalizations in Southeast Asia, and the CCoV-HuPn-2018 strain has been found in people with respiratory illness in Thailand, Vietnam, and Arkansas.

Given the potential for these viruses to evolve and spread, what steps do you think are most important for public health officials to prioritize?