Certain flu virus strains in dogs are developing mutations that could make them more likely to spread to humans, new research suggests.
Scientists in China and at the University of China studied H3N2 avian influenza viruses that were transmitted to dogs around 2006. They found that since then, H3N2 canine influenza viruses have:
- Become able to recognize the human-like SAα2,6-Gal receptor.
- Showed gradually increased hemagglutination (HA) acid stability and replication ability in human airway epithelial cells.
- Acquired a 100% transmission rate via respiratory droplets in a ferret model.
“We also found that human populations lack immunity to H3N2 CIVs, and even preexisting immunity derived from the present human seasonal influenza viruses cannot provide protection against H3N2 CIVs.” the researchers wrote. “Our results showed that canines may serve as intermediates for the adaptation of avian influenza viruses to humans.”
The study involved dogs in nine provinces or municipalities of China from 2012 to 2019. The findings were published in the journal Epidemiology and Global Health, Microbiology and Infectious Disease.