Pathogen causing gastritis found not to have originated in pigs, after all

14 Dec 2017 | Back to News, Publications and Annual Reports

A mysterious bacterium's triple jump

One of the pathogens causing gastritis is the Helicobacter suis bacterium. This bacterium often causes stomach issues in pigs, but has also been known to infect humans. You would therefore expect this bacterium to have originated in a pig species living in the wild, such as the wild boar. Yet nothing is further from the truth.  

We have now shown that this bacterium probably does not exist in wild boar at all. Previous studies showed that Helicobacter suis does exist in rhesus and crab-eating macaques. Naturally, this piqued our interest.

Our discovery: from monkeys to pigs

In order to learn more about the origin of this mysterious pig-associated bacterium, a group of scientists, including BPRC-affiliated researchers, followed the traces they had found, and so discovered that Helicobacter suis had been transmitted by primates to pigs. It seems likely that this happened between 15,000 and 100,000 years ago. After that the bacterium spread to domesticated pigs, and from domesticated pigs the bacterium may occasionally spread to humans. It is quite a fascinating triple jump.

Conclusion: keep a close eye on pathogens in animals

Bacteria, viruses and parasites will occasionally spread from animals to humans, in whom they will then provoke a disease. That pathogens causing disease in humans should originate from primates should not surprise us. After all, primates are very similar to humans and are genetically 93% identical to us. What is new, however, is the fact that this bacterium, which until recently was only associated with pigs, actually originated in primates. This confirms and emphasises the importance of keeping a very close eye on which pathogens may occur in primates.

If you wish to learn more about how the researchers made their discovery, please read the article about the study in ISME Journal, an academic journal. You can find it here.