Determining the Scope of Campylobacter Infection and Its Post-Infectious Symptoms

Abstract

Campylobacter species are the most common bacterial cause of diarrheal illness in the United States and are estimated to cause up to 1.5 million cases of illness per year in the U.S. alone. There has been increasing evidence that after an acute infection by Campylobacter spp., some symptoms may persist and develop further comorbidities such as post-infectious irritable bowel syndrome (PI-IBS). This prospective cohort study aims to determine the relationship between acute symptoms and the incidence of PI-IBS after a diagnosis of campylobacteriosis. Within 6-months of follow-up, of 119 patients with laboratory confirmed Campylobacter infection, there were 19 cases with symptoms fitting the criteria of PI-IBS leading to an incidence of 16% in this population. No acute symptoms were shown to be significant except the presence of chronic conditions before acute infection, which showed a positive association with developing PI-IBS (RR: 2.37, 95% CI: 1.00, 5.58). Further characterization of acute symptoms of campylobacteriosis as risk factors for PI-IBS is an important step to understanding the next steps of preventing its occurrence. The sporadic nature of Campylobacter infections leads to an underreporting to our public health agencies and thus an under-estimate of their true burden. The analysis of epidemiological interview data with genomic data will increase the likelihood of finding clusters of cases that were not detected through public health surveillance alone. 2018-2019 data from the FoodNet catchment area in the Denver, Colorado area was analyzed via whole genome sequencing (WGS) for clusters of Campylobacter cases, where six clusters were identified that were not originally linked to each other through the epidemiologic data alone. Three clusters had strains with the same gene sequence type (ST) and core genome multi-locus sequence type (cgMLST). WGS may prove critical in accurately identifying previously unidentified Campylobacter clusters when supported by epidemiological data.