Shiga toxin-producing Escherichia coli in Animals related to Cases of Bloody Diarrhea or Hemolytic Uremic Syndrome and Prevalence in Rodents in the City of Buenos Aires

Abstract

INTRODUCTION: Shigatoxigenic Escherichia coli (STEC) is an endemic pathogen in Argentina, which causes bloody diarrhea (BD) and/or hemolytic uremic syndrome (HUS). The co-relation between HUS and contaminated food has been documented, although the source of infection was not always established. Person-to-person route of infection is relevant. Taking into account previous STEC prevalence data in companion animals and the habits of human-animal coexistence in urban centers, it is necessary to evaluate pet-to-person transmission. On the other hand, rodents may also play an epidemiologic role in the endemic transmission. OBJECTIVE: To study potential animal reservoirs related to HUS and BD cases in the City of Buenos Aires and to estimate the prevalence of STEC in rodents. METHODS: An intervention was conducted in 28 cases of HUS and 49 of BD. Screening for STEC was performed by PCR from rectal swabs of linked animals to each case. The prevalence in rodents was estimated by PCR from rectal swabs. RESULTS: STEC strains were isolated in 1/10 dogs and 1/3 cats cohabiting with HUS cases, and in 1/9 cats in contact with DAS cases. Rattus rattus was host of STEC strains in 33% of the animals captured in HUS areas. In rodents, the prevalence was 3.1%. CONCLUSIONS: STEC strains circulate in animals that live with or share at least the same habitat with the population at risk, and could participate in the transmission of the agent. It is necessary to re-evaluate health interventions both in outbreaks and in control programs of HUS/BD.