Isolation, toxin gene profiling, and phylogenetic analysis of Clostridium perfringens in Egyptian fruit bats: public health and epidemiological implications

TL;DR

This study finds that Egyptian fruit bats can carry toxin-producing Clostridium perfringens bacteria, which could pose public health risks due to their potential to spread harmful strains.

Contribution

This is the first study in Egypt to detect and analyze Clostridium perfringens in bats, revealing their potential role as reservoirs for zoonotic pathogens.

Findings

C. perfringens was detected in 31% of bat samples, with toxin gene cpa present in all isolates.

Phylogenetic analysis showed genetic similarity between bat isolates and strains from domestic animals and environmental sources.

Type C strains were predominant, suggesting epidemiological significance and possible horizontal gene transfer.

Abstract

Clostridium perfringens (C. perfringens) is spore forming, toxin producing bacterium causing serious diseases in both animals and man and its presence in bats, especially the Egyptian fruit bat, are ecologically important yet increasingly interact with human environments due to habitat changes which raise the concerns about their role as reservoirs for zoonotic pathogens. This study, the first of its kind in Egypt, investigates the occurrence and characteristics of C. perfringens in bats to evaluate their potential role as reservoirs for this toxin-producing, environmentally persistent foodborne pathogen. Fifty fruit bats were captured using mist nets at foraging and roosting sites. The bats were identified morphologically, and for each bat, fecal swabs and internal organs were collected (n = 100). The samples were examined bacteriologically to investigate the C. perfringens detection then confirmed biochemically and via gram staining. DNA was extracted, and toxin genotyping was conducted using multiplex PCR for main toxin genes “ cpa, cpb, etx, ia, netB, cpe” whereas uniplex PCR for cpb2. Sequencing and phylogenetic analysis of cpb2 gene from four isolates were analyzed to determine genetic relatedness. Out of 100 samples examined, C. perfringens was detected in 31% (31/100) of samples, with similar occurrence in internal organs (30%) and fecal swabs (32%). All isolates carried the cpa gene (100%), while cpb, cpe, and cpb2 were detected in 83.9%, 64.5%, and 64.5% of isolates, respectively; ia, etx, netB genes were not detected. Notably, 35.5% of isolates harbored both cpe and cpb2 genes. Toxinotyping showed type C as predominant (83.9%), followed by type F (12.9%) and type A (3.2%), highlighting the epidemiological significance of type C strains. Phylogenetic analysis of cpb2 sequences indicated high genetic similarity among bat isolates and close relationships with strains from domestic animals and environmental sources, suggesting possible shared habitats and horizontal gene transfer. These findings identify bats as potential reservoirs of toxigenic C. perfringens, reinforcing the importance of integrating wildlife into One Health surveillance strategies. This study reports the first detection of C. perfringens from Egyptian fruit bats. Phylogenetic analysis revealed close genetic links to strains from domestic animals and environmental sources and these findings highlight bats’ potential role as reservoirs of virulent C. perfringens.

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