Pesquisadores of Universidade Federal of Rio Grande of Sul identified the presence of Acinetobacter baumannii in water samples collected at four points in Porto Alegre. One of the samples, obtained close to Estação of Bombeamento of Água Pluvial Menino Deus, showed resistance to all 14 antimicrobials tested, including ceftazidime, imipenem, meropenem and ciprofloxacin. The finding results from analyzes of the ClimaRes WaSH and CLIMASANO projects, which monitor antimicrobial resistance in aquatic environments.
The bacteria was located in four different locations: Lami beach, Ipanema beach at Zona Sul, Guaíba near the mouth of the Dilúvio stream and near EBAP Menino Deus. Nos other three collection points, the isolates also exhibited resistance to multiple antibiotics, such as cefotaxime, ceftriaxone and cefepime.
Bactéria classified as one of the most dangerous globally
Acinetobacter baumannii was listed by Organização Mundial of Saúde in 2024 among the most dangerous bacteria in the world. The WHO uses specific criteria for this classification:
- Taxas of high mortality in infections
- Número increasing number of confirmed cases
- Impacto significant in public health
- Desenvolvimento accelerated antimicrobial resistance
- Transmissibilidade between hosts
- Limitação in available therapeutic options
- Ausência of new drugs in development
The bacterium has great clinical relevance, especially when it develops multidrug-resistant profiles such as the one identified in Porto Alegre.
Análise in depth and next steps
The researchers announced that they will carry out genomic sequencing of the isolated bacteria to investigate the resistance profile in detail. The intention is to evaluate a possible genetic relationship with strains responsible for an outbreak of A. baumannii that occurred in April in the neonatal ICU of Hospital Fêmina, which resulted in the death of a premature baby.
The team believes that transmission to the hospital did not occur through water from Guaíba. Segundo researchers, the most likely hypothesis is that hospital waste is released into the sewage system without adequate treatment, allowing the bacteria to spread into aquatic environments. The next step involves testing the susceptibility of the isolates to polymyxin B, one of the last therapeutic resources available for infections with extremely resistant strains.
Esclarecimento about drinking water
Departamento Municipal of Água and Esgoto stated that the find refers exclusively to natural environments and is not related to the treated water distributed through Porto Alegre’s taps. Monitoring antimicrobial resistance in environmental waters remains a priority for researchers and health agencies, given the potential for the spread of resistant strains.