My guess would be that these people had some condition to make them susceptible to bacterial infections, and if it hadn't been the dog kisses, it would have been something else. When I worked in a medical floor of a hospital, I learned there are many types of bacteria or fungi that most of us are able to ward off, but someone who's immunocompromised or otherwise susceptible might die from it. Sadly, I witnessed many such cases.

It's truly tragic what these people experienced, and sadly capitalism dictates that we must find a way to monetize their loss. That's one reason I call it irresponsible, along with the use of FUD to gain clicks, causing people to fear things they should not.

You or I could probably let a dog lick a gaping wound and be just fine (not that I'd recommend it lol)