Mystery Dog Illness 2025. In 2023, hundreds of dogs across as many as 16 states contracted a mysterious respiratory illness that started spreading in the u.s. Mysterious and fatal dog respiratory illness now reported in 14 states:

Canine respiratory infections, especially dog flu, are common, often causing outbreaks in shelters and doggy day cares. The technology and science might exist to fight a dog pandemic, but any response would depend on what kind of illness we found ourselves dealing with—and whether it could.