Pathogenic potential of Aeromonas hydrophila isolated from surface waters in Kolkata, India

Abstract

Members of the genus Aeromonas (family Aeromonadaceae) are medically important, Gramnegative, rod-shaped micro-organisms and are ubiquitous in aquatic environments. Aeromonas species are increasingly recognized as enteric pathogens; they possess several virulence factors associated with human disease, and represent a serious public health concern. In the present study, putative virulence traits of Aeromonas hydrophila isolates collected from different natural surface waters of Kolkata, India, were compared with a group of clinical isolates from the same geographical area using tissue culture and PCR assays. Enteropathogenic potential was investigated in the mouse model. Of the 21 environmental isolates tested, the majority showed cytotoxicity to HeLa cells (81 %), haemolysin production (71 %) and serum resistance properties (90 %), and they all exhibited multi-drug resistance. Some of the isolates induced fluid accumulation (FA ratio¢100), damage to the gut and an inflammatory reaction in the mouse intestine; these effects were comparable to those of clinical strains of A. hydrophila and toxigenic Vibrio cholerae. Interestingly, two of the isolates evoked a cell vacuolation effect in HeLa cells, and were also able to induce FA. These findings demonstrate the presence of potentially pathogenic and multi-drug-resistant A. hydrophila in the surface waters, thereby indicating a significant risk to public health. Continuous monitoring of surface waters is important to identify potential waterborne pathogens and to reduce the health risk caused by the genus Aeromonas.

Influence of different dietary carbohydrate sources on the growth and intestinal microbiota of Litopenaeus vannamei at low salinity

“…Furthermore, opportunistic pathogens, such as Desulfovibrio and Aeromonas, increased in the corn starch‐fed group (Bhowmik et al . ; Lu et al . ).…”

“…A number of glycolytic genes harboured in Bacteroidetes help the host to degrade the dietary fibre that is resistant to digestion by human enzymes, but the abundance of Bacteroidetes decreased in the corn starchfed group in the present work. Furthermore, opportunistic pathogens, such as Desulfovibrio and Aeromonas, increased in the corn starch-fed group (Bhowmik et al 2009;Lu et al 2014).…”

PHENOTYPING, VIRULENCE CHARACTERISTICS OF <i>AEROMONAS</i> SPECIES AND THE EFFECTS OF ESSENTIAL PLANT OILS AS ANTIMICROBIAL AGENTS AGAINST PATHOGENIC ISOLATES FROM DIFFERENT SOURCES

“…Trypticase Soy Broth (TSB; Hi Media) was used for assessing production of various toxins and the cell-free filtrate was used for the tissue culture (Bhowmik et al, 2009) • Tissue culture assay. The tissue culture assay was performed using HEp-2 cells as described previously (Bag et al, 2008).…”

“…These proteins are known as virulence factors that cause disease in fish and humans. Aerolysin is a representative virulence factor of Aeromonas and was reported to function as hemolysins and cytolytic enterotoxins (Bhowmik et al, 2009).…”

Prevalence of antimicrobial resistant Aeromonas in chicken and fish washings

“…Literatures from other part of the world revealed widespread distribution of Aeromonas species in meat, fish and fresh water environment (Hanninen and Sitonen, 1995;Akan et al, 1998;Neyts et al, 2000;Villari et al, 2000;Dallal et al, 2012). Presence of Aeromonas species in foods of animal origin, water environment and retail foods as evident from the available literatures may indicate that these products can act as possible source of vehicles for dissemination of food-borne Aeromonas gastroenteritis (Neyts et al, 2000;Bhowmik et al, 2009). Present findings emphasize the need of more intensive study on distribution of aeromonads in soil, water environment and foods of animal origin considering its public health implications.…”