Acinetobacter calcoaceticus-baumannii complex prevalence, spatial-temporal distribution, and contamination sources in...

Area of Science:

• Environmental microbiology
• Public health microbiology
• Infectious diseases

Background:

• The Acinetobacter calcoaceticus-baumannii (ACB) complex comprises opportunistic pathogens causing nosocomial infections.
• Acinetobacter baumannii is a growing global threat due to increasing antibiotic resistance.
• Understanding ACB complex occurrence in non-nosocomial environments is crucial.

Purpose of the Study:

• To investigate the prevalence, distribution, and diversity of pathogenic ACB complex in diverse aquatic systems.
• To assess the spatial-temporal distribution of ACB complex species within a regional watershed.
• To identify potential health risks associated with ACB complex in various water sources.

Main Methods:

• Isolation, quantification, and confirmation of acinetobacters using genus- and ACB complex-specific PCR assays.
• Sampling across agricultural, raw drinking water intake, recreational beach, and WWTP effluent sites.
• Analysis of seasonal variations and impact of effluent chlorination on ACB prevalence.

Main Results:

• ACB complex species were detected in all sampled aquatic environments.
• Acinetobacter calcoaceticus was most frequent in agricultural waters; A. baumannii predominated in de-chlorinated WWTP effluent.
• Significant seasonal differences were observed in agricultural surface waters; effluent chlorination impacted prevalence in WWTP samples.

Conclusions:

• The widespread presence of ACB complex in diverse water sources indicates potential risks for community-acquired opportunistic infections.
• Wastewater effluent discharged into rivers can serve as a reservoir for ACB complex.
• Findings support the need for monitoring programs for ACB complex in regional waters.