Question: Is there certain bacteria that can affect both humans and domestic creatures in deadly ways?

Franco Falcone answered on 15 Jun 2016:

@Dr Autismo thanks for the challenging question

A disease which can be transmitted from animals to humans is called a ‘zoonotic disease’. These can be viruses, bacteria, fungi or parasites. And one can add prions to the list as well. I shall limit my answer to bacteria.

Many bacteria are very specialised and only infect a specific host. For example, humans have a bacterium called Helicobacter pylori in their stomachs, cats have Helicobacter felis in their stomach, pigs have Helicobacter suis in their stomach, and so on, but there is little infection across different species of animals (so you cannot get your cat’s stomach bugs for example).

However there are also many examples of bacteria that are more ‘generalists’, in the sense that they can infect more than one animal. Well known examples are Salmonella (in or on chicken), Escherichia coli O157:H7 (in raw milk); Campylobacter (also found in or on raw or undercooked chicken), but also very very dangerous bacteria such as anthrax.

The list is longer but I’ll keep it short. What can you do? Well, you could not eat any chicken for example, or, if you eat chicken, make sure it’s well cooked, same advice goes for fish or any type of meat. Eating of raw meat is always a health hazard, there’s lots of parasites that you can get from this.

This is also one reason why humans are less prone to parasitic infection than other animals: they are the only who cook their meat (or become vegetarian/vegan as in my family).