Abstract Coastal regions are frequently affected by natural hazards, making them vulnerable to the spread of antibiotic-resistant pathogens. This study assessed microbial contamination by examining the prevalence of multidrug resistance and the presence of virulence genes in various water sources in the coastal regions of Kochi, Kerala. Among 265 isolates, the most prevalent multidrug-resistant pathogens belonged to the genera Escherichia, Vibrio, Enterobacter, Klebsiella, Pseudomonas, Proteus, Citrobacter, Aeromonas, and Acinetobacter. All isolates exhibited varying levels of antibiotic resistance, ranging from 3% to 68.7%. Significantly higher resistance (p < 0.05) was observed towards beta-lactams and ceftriaxone, followed by colistin. Overall, 72.5% of isolates were multidrug resistant and 53.2% were classified as high risk based on their resistance profiles. Escherichia coli (0.83) and Proteus mirabilis (0.77) demonstrated the highest multiple antibiotic resistance (MAR) indices. A strong positive correlation existed between the MAR index and biofilm formation (p < 0.0001). Genotypically, blaTEM was the most prevalent ESBL encoding gene, detected in 42% of the isolates. Isolates often carried a range of resistance genes, including blaTEM, blaSHV, blaOXA, alongside virulence genes such as toxR, hlyA, aer, act, magA. Notably, 42% of the Klebsiella pneumoniae strains were hypermucoviscous, harbouring magA genes associated with increased hypervirulence. This study provides crucial baseline data for public health interventions, highlighting the urgent need for enhanced water management strategies in flood-impacted coastal regions to mitigate the spread of these resistant and virulent pathogens. Research highlights <UnorderedList Mark="Bullet"> <ItemContent> Recurring inundations are linked to microbial contamination of domestic water sources by polluted coastal waters. </ItemContent> <ItemContent> High prevalence of multidrug-resistant and hypervirulent bacterial pathogens are encountered in Coastal Kochi. </ItemContent> <ItemContent> High-risk strains, including ESKAPE pathogens, pose substantial healthcare and community infection risks. </ItemContent> <ItemContent> Biofilms enhance bacterial survival in drinking water systems, complicating eradication. </ItemContent> <ItemContent> Co-occurrence of multidrug resistance and, hypervirulence among the bacterial pathogens in water indicates high potential for difficult-to-treat infections in densely populated, flood-prone areas. </ItemContent> </UnorderedList>

Inundation-driven microbial contamination of water sources with multidrug-resistant pathogens: A case study from a densely populated coastal island, India

期刊论文
发表日期：

2025年10月29日

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Jesmi Yousuf,
Reshma Silvester,
P A Aneesa,
Jasna Vijayan,
K Hafza,
K M Mujeeb Rahiman,
A A Mohamed Hatha

摘要

Abstract

Coastal regions are frequently affected by natural hazards, making them vulnerable to the spread of antibiotic-resistant pathogens. This study assessed microbial contamination by examining the prevalence of multidrug resistance and the presence of virulence genes in various water sources in the coastal regions of Kochi, Kerala. Among 265 isolates, the most prevalent multidrug-resistant pathogens belonged to the genera Escherichia, Vibrio, Enterobacter, Klebsiella, Pseudomonas, Proteus, Citrobacter, Aeromonas, and Acinetobacter. All isolates exhibited varying levels of antibiotic resistance, ranging from 3% to 68.7%. Significantly higher resistance (p < 0.05) was observed towards beta-lactams and ceftriaxone, followed by colistin. Overall, 72.5% of isolates were multidrug resistant and 53.2% were classified as high risk based on their resistance profiles. Escherichia coli (0.83) and Proteus mirabilis (0.77) demonstrated the highest multiple antibiotic resistance (MAR) indices. A strong positive correlation existed between the MAR index and biofilm formation (p < 0.0001). Genotypically, bla_TEM was the most prevalent ESBL encoding gene, detected in 42% of the isolates. Isolates often carried a range of resistance genes, including bla_TEM, bla_SHV, bla_OXA, alongside virulence genes such as toxR, hlyA, aer, act, magA. Notably, 42% of the Klebsiella pneumoniae strains were hypermucoviscous, harbouring magA genes associated with increased hypervirulence. This study provides crucial baseline data for public health interventions, highlighting the urgent need for enhanced water management strategies in flood-impacted coastal regions to mitigate the spread of these resistant and virulent pathogens.

Research highlights

Recurring inundations are linked to microbial contamination of domestic water sources by polluted coastal waters.

High prevalence of multidrug-resistant and hypervirulent bacterial pathogens are encountered in Coastal Kochi.

High-risk strains, including ESKAPE pathogens, pose substantial healthcare and community infection risks.

Biofilms enhance bacterial survival in drinking water systems, complicating eradication.

Co-occurrence of multidrug resistance and, hypervirulence among the bacterial pathogens in water indicates high potential for difficult-to-treat infections in densely populated, flood-prone areas.