Microbial source tracking and antimicrobial resistance in one river system of a rural community in Bahia, Brazil

Abstract

Use of antibiotics inevitably leads to antimicrobial resistance. Selection for resistance occurs primarily within the gut of humans and animals as well as in the environment through natural resistance and residual antibiotics in streams and soil. We evaluated antimicrobial resistance in Gram negative bacteria from a river system in a rural community in Bahia, Brazil. Water was collected from the Jiquiriçá and Brejões rivers and the piped water supply. Additionally, stools were collected from a random sample of residents, cows, pigs and horses near the river. The samples were screened for bacteria resistant to ciprofloxacin, cefotaxime, and meropenem and identified biochemically at the genus and species levels. Microbial source tracking demonstrated that ruminant and human fecal contamination increased as the rivers neared the village center and decreased after the last residence. Antibiotic bacteria were identified from all samples (n = 32). No bacteria were resistant to carbapenems, but the majority of the enterobacteria were resistant to ciprofloxacin, even though this class of antibiotics is not commonly used in food animals in this region. Considering these facts, together with the pattern of human fecal contamination, a human source was considered most likely for these resistant isolates.

Human Colonization with Antibiotic-Resistant Bacteria from Nonoccupational Exposure to Domesticated Animals in Low- and Middle-Income Countries: A Critical Review

“…coli or bla CTX‑M‑1 genes were detected in humans, animals, and drinking water in India, though the prevalence was highest in humans. , Carbapenem-resistant Pseudomonas aeruginosa isolates clonally related to the hospital-associated lineage ST233 were isolated from dog owners, dogs, and a sofa, balcony surface, and water cooler in a Brazilian household. Additionally, humans, livestock, and water (drinking water or river) harbored Enterobacteriaceae resistant to imipenem and ciprofloxacin in India and rural Brazil, respectively, despite imipenem and ciprofloxacin not being widely used in agriculture in the respective regions. − …”

Processos fermentativos direcionados a produção de antibióticos: uma alternativa a resistência de bactérias

“…De acordo com Moretto et al (2021) novas bactérias resistentes a antimicrobianos podem se originar em países de baixa renda, e este fato pode ser explicado em parte pela falta de saneamento que contribui para a mistura de bactérias fecais e transmissão de resistência via plasmídeos conjugativos ou a presença de concentrações subletais de antibióticos.Destaca-se que nos países em desenvolvimento, 80% dos antimicrobianos são consumidos fora do ambiente hospitalar.…”

Antibiotic Resistance and Sewage-Associated Marker Genes in Untreated Sewage and a River Characterized During Baseflow and Stormflow

“…Patterns of increased human fecal pollution and ARGs were previously identified in environmental waters (Ahmed et al, 2018;Reynolds et al, 2020;Stange and Tiehm, 2020;Moretto et al, 2022). Abundances of 47 ARGs in several storm drain outfalls during dry and wet weather in Tampa Bay, FL, United States along with sewage-associated Bacteroides HF183 and crAssphage markers were monitored (Ahmed et al, 2018).…”