Hospital liquid waste contaminated with multidrug-resistant bacteria raises a public health hazard alert in Brazil

The spread of multidrug-resistant bacteria (MDR) is a global concern because it poses a serious threat to public health. The inadequate handling of Health Services Waste (HSW) and, therefore, the incorrect disposal of infected liquids can cause contamination of the environment, the emergence of diseases caused by MDR bacteria, and the loss of the population's quality of life. The present study aimed to survey the bacteria and their antimicrobial resistance profiles, present in the liquid residues from infected surgeries performed in five years, often discharged into the sewage network of a large tertiary hospital located in the city of Uberlândia, which is considered one of the main economic and demographic centers of Brazil. A systematic and retrospective survey of the medical records of patients who underwent infected surgeries from January 2015 to December 2019 was carried out at the referred hospital. The bacterial species were previously identified and characterized for the antimicrobial susceptibility profile by the VITEK 2 automated system (bioMérieux, Brazil). In the evaluated period, 1658 infected surgeries were performed and the results showed 661 bacterial strains distributed in 48 different species, being Staphylococcus aureus the most prevalent species. The vast majority (85.6%) showed some type of antimicrobial resistance among these strains, with more than half (54.6%) being MDR. The results of this work raise an alert and concern for the risks to the environment and public health by dumping these infected liquid wastes directly into the sewage system without proper prior decontamination.