Helicobacter pylori virulence genotypes in Bogota River and wastewater treatment plants in Colombia

Background: Helicobacter pylori is a bacterium that infects 70%-80% of the population in Colombia, causing chronic gastritis in all those infected and gastric cancer in 1%-2% of those infected. In Colombia, some studies have identified the presence of vacA and cagA genes in environmental samples such as treated, surface, and wastewater, but they have not been evaluated in the Bogota River. For this, the aim of this study was to identify the virulence genotypes of H. pylori present in samples from the Bogota River and domestic wastewater treatment plants (WWTPs).Materials and Methods: A total of 75 water samples (51 from the Bogota River and 24 from wastewater treatment plants) were collected. The presence of H. pylori DNA and its virulence genotypes was determined by polymerase chain reaction (PCR).Results: The presence of H. pylori DNA was demonstrated in 44% (33/75) of the samples, obtaining 63.6% (21/33) from the Bogota River and 36.4% (12/33) from the WWTPs. The most prevalent H. pylori genotype was cagA (-) and vacAm1/s1/i1 being the most virulent of the vacA gene.Conclusions: This is the first study in Colombia that determines the cagA and vacA genotypes in surface water and WWTPs, indicating the circulation of virulent genotypes in the population. The presence of this pathogen in the waters can be represent a risk to the health of the surrounding population since these waters are reused by the communities for different purposes.

Automated summary

This study identified the presence of H. pylori DNA in the Bogota River and wastewater treatment plants, demonstrating the potential risk of this pathogen in water sources.