Bartonella bacilliformis is a pathogen that is endemic in some areas of the Andean region of Peru, southern Ecuador and southern Colombia. This pathogen causes so-called Carrion's disease, a biphasic disease with acute and chronic phases (called Oroya fever and "Peruvian wart" respectively1-3). In the absence or delay of antibiotic treatment, the mortality rate in the acute phase is up to 88%1. The acute phase is characterised by fever and severe anaemia and may be followed, several weeks or months later, by the chronic eruptive phase due to endothelial cell proliferation2. No animal reservoir has been identified to date and it is considered that healthy carriers act as a pathogen reservoir in endemic areas

Objective: To determine the variations in the composition of the intestinal microbiota in asymptomatic children infected with Helicobacter pylori in comparison with children without the infection. Results: Children infected with H. pylori doubled their probability of presenting 3 of 9 genera of bacteria from the gut microbiota, including: Proteobacteria (p = 0.008), Clostridium (p = 0.040), Firmicutes (p = 0.001) and Prevotella (p = 0.006) in comparison to patients without the infection. We performed a nutritional assessment and found that growth stunting was statistically significantly higher in patients infected with H. pylori (p = 0.046).

Background: Human fascioliasis is considered an endemic and hyper-endemic disease in the Peruvian Andean valleys. Our objective was to determine variations in the composition of the gut microbiota among children with Fasciola hepatica and children who do not have this parasitosis. (2) Method: A secondary analysis was performed using fecal samples stored in our biobank. The samples were collected as part of an epidemiological Fasciola hepatica cross-sectional study in children from 4 through 14 years old from a community in Cajamarca, Peru. (3) Results: In a comparison of the bacterial genera that make up the intestinal microbiota between the F. hepatica positive and negative groups, it was found that there are significant differences in the determination of Lactobacillus (p = 0.010, CI: 8.5–61.4), Bacteroides (p = 0.020, CI: 18.5–61.4), Clostridium (p < 0.001, CI: 3.5–36.0), and Bi...