A Meat Link to UTIs, Sepsis
Using a novel approach to identify E coli, investigators find approximately 8% of the bacterium’s isolates were foodborne zoonotic strains.
Photo courtest of Claudio Schwarz/ Unsplash
A new study estimates meat causes more than 480,000 urinary tract infections (UTIs) in the United States annually. The study’s investigators developed a novel approach for predicting the origins of clinical E coli infections caused by foodborne zoonotic E coli (FZEC) strains of the bacterium.
“Our findings also implies that, collectively, FZEC strains could cause more UTIs annually than any non-E coli uropathogenic species (e.g., Klebsiella pneumoniae) or any of the major human-associated extraintestinal pathogenic E. coli lineage,” the study’s authors wrote.
The study was published in One Health.
The investigators pointed out there was a long history of evidence of E coli infections stemming from foodborne zoonotic transmission. The study’s authors set out to find origins of the clinical E coli isolates and whether they came from human or zoonotic sources.
This study’s authors identified 17 source-associated mobile genetic elements (MGEs) and utilized a Bayesian latent class model to predict the origin of E coli isolates. They approximated that 8% of human extraintestinal E coli infections in the studied community (Flagstaff, AZ) were caused by FZEC strains.
They identified E coli strains in individuals looking at chicken, turkey, and pork. All the meat was produced in the US, and the studied population were from Flagstaff, the local suburbs, and visitors both from the US and internationally.
In trying to identify the source-associated mobile genetic elements, the investigators constructed a pan-genome using their isolate collection. Their pan-genome was made up of 60,648 genes, including 2940 core genes and 57,474 accessory genes.
Next, they performed a genome-wide association study to identify accessory genes that were associated with specific sample types. This revealed 366 non-redundant source-associated accessory genes.
"Most of these accessory genes (96%) were part of multigene clusters (n = 46), of which 17 (37%) bore hallmarks of MGEs," the investigators wrote.
As another significant finding, the investigators pointed out that foodborne E coli strains were just as likely to cause sepsis, cystitis, and asymptomatic bacteriuria as were human-origin E coli.
“The clinical syndromes described among the 1162 clinical cases included asymptomatic bacteriuria (41.2%), cystitis (25.2%), pyelonephritis (9.2%) and sepsis/urosepsis (8.6%). Diagnoses were unavailable for 183 (15.7%) cases,” the investigators wrote. “The only difference in clinical syndrome distribution between FZEC-associated cases and human-origin cases was that pyelonephritis was more common among human-origin cases (9.9%, vs. 2.0%: P = 0.01). Notably, FZEC-associated cases were as likely to qualify as sepsis or cystitis as putative human-origin cases,” the investigators wrote.
The investigators believe their novel approach can be replicated more broadly to determine the highest-risk FZEC, the sources, and develop strategies around extraintestinal E coli infections.
