What Dr. Humber said:

"Epidemiology. Non typhoidal salmonellosis is a worldwide disease of humans and animals. Main reservoir: animals; main transmission is via food, right?

"Typhoidal salmonellosis is different, it’s spread mainly from person-to person via the fecal-oral route and has no significant animal reservoirs. Asymptomatic human carriers often implicated."

Dr. Jessie's translation:

"Okay, how does the disease spread and cause epidemics?

"The strains of salmonella that don’t cause enteric fever can be found all over the world. They primarily dwell in animals.

"The strains that do cause enteric fever are different. They don’t hide out in animals - they hide out in humans who often don’t show any symptoms. Both diseases usually get to people through food or drink."