Trends in the Epidemiology of Pandemic and Non-pandemic Strains of Vibrio parahaemolyticus Isolated from Diarrheal Patients in Kolkata, India

Abstract

A total of 178 strains of V. parahaemolyticus isolated from 13,607 acute diarrheal patients admitted in the Infectious Diseases Hospital, Kolkata has been examined for serovar prevalence, antimicrobial susceptibility and genetic traits with reference to virulence, and clonal lineages. Clinical symptoms and stool characteristics of V. parahaemolyticus infected patients were analyzed for their specific traits. The frequency of pandemic strains was 68%, as confirmed by group-specific PCR (GS-PCR). However, the prevalence of non-pandemic strains was comparatively low (32%). Serovars O3:K6 (19.7%), O1:K25 (18.5%), O1:KUT (11.2%) were more commonly found and other serovars such as O3:KUT (6.7%), O4:K8 (6.7%), and O2:K3 (4.5%) were newly detected in this region. The virulence gene tdh was most frequently detected in GS-PCR positive strains. There was no association between strain features and stool characteristics or clinical outcomes with reference to serovar, pandemic/non-pandemic or virulence profiles. Ampicillin and streptomycin resistance was constant throughout the study period and the MIC of ampicillin among selected strains ranged from 24 to >256 µg/ml. Susceptibility of these strains to ampicillin increased several fold in the presence of carbonyl cyanide-m-chlorophenyldrazone. The newly reported ESBL encoding gene from VPA0477 was found in all the strains, including the susceptible ones for ampicillin. However, none of the strains exhibited the β-lactamase as a phenotypic marker. In the analysis of pulsed-field gel electrophoresis (PFGE), the pandemic strains formed two different clades, with one containing the newly emerged pandemic strains in this region.

Mice with Streptozotocin-Induced Hyperglycemia are Susceptible to Invasive Enteric Bacterial Infection

“…Globally, the primary causative agents of gastroenteritis in both developed and developing countries are Shigella flexneri, Vibrio parahaemolyticus, and various strains of the Salmonella enterica serovar Typhimurium (9)(10)(11). While the resulting disease is usually mild and self-limiting, it can be fatal, particularly in immunocompromised individuals (11).…”

The First Report of <i>Vibrio parahaemolyticus</i> Strain O10:K60 in Japan, a New Combination of O and K Serotypes Isolated from a Patient with Gastroenteritis

“…Although we could not find any reports about this O10:K60 serotype at the time that our experiments were performed, a study of the emergence of this serotype from 2011 to 2012 in India was recently published (37). Thus, it is plausible that this serotype spread among other countries and was imported to Japan.…”

Combination of Multilocus Sequence Typing and GS‐PCR Reveals an Association of Pandemic Vibrio parahaemolyticus Clone with Clinical and Seafood Isolates

“…We found about 50% of the clinical isolates and 43% of the seafood isolates carried the GS‐PCR marker. The pandemic group included the most frequent serotype O3:K6 as well as new members, including O1:K25, O1:KUT, and O4:K68 (Chao et al., ; Nair et al., ; Pazhani et al., ). In our study, the major serotypes among the clinical pandemic isolates were O3:K6, O1:K25, O1:KUT, O3:K68, and O4:K68.…”