Multidrug resistant Vibrio cholerae O1 from clinical and environmental samples in Kathmandu city

Abstract

BackgroundCholera, an infectious disease caused by Vibrio cholerae, is a major public health problem and is a particularly burden in developing countries including Nepal. Although the recent worldwide outbreaks of cholera have been due to V. cholerae El Tor, the classical biotypes are still predominant in Nepal. Serogroup O1 of the V. cholerae classical biotype was the primary cause of a cholera outbreak in Kathmandu in 2012. Thus, this study was designed to know serotypes and biotypes of V. cholerae strains causing recent outbreak with reference to drug resistant patterns. Moreover, we also report the toxigenic strains of V. cholerae from both environmental and clinical specimens by detecting the ctx gene.MethodsTwenty four V. cholerae (n = 22 from stool samples and n = 2 from water samples) isolated in this study were subjected to Serotyping and biotyping following the standard protocols as described previously. All of the isolates were tested for antimicrobial susceptibility patterns using the modified Kirby-Bauer disk diffusion method as recommended by CLSI guidelines. The screening of the ctx genes (ctxA2-B gene) were performed by PCR method using a pair of primers; C2F (5′-AGGTGTAAAATTCCTTGACGA-3′) and C2R (5′-TCCTCAGGGTATCCTTCATC-3′) to identify the toxigenic strains of V. cholerae.ResultsAmong twenty four V. cholerae isolates, 91.7% were clinical and 8.3% were from water samples. Higher rate of V. cholerae infection was found among adults of aged group 20–30 years. All isolates were serogroups O1 of the V. cholerae classical biotype and sub serotype, Ogawa. All isolates were resistant to ampicillin, nalidixic acid and cotrimoxazole. 90.9% were resistant to erythromycin however, tetracycline was found to be the most effective drug for the isolates. All isolates were multidrug resistant (MDR) and possessed a ctx gene of approximately 400 base pairs indicating the toxigenic strains.ConclusionHundred percent strains of V. cholerae were MDR possessing a ctx gene. It suggests that toxigenic strains be identified and proper antibiotic susceptibility testing be conducted. This will allow effective empirical therapy to be used to treat and control cholera.

Phenotypic and antibiogram pattern ofV. choleraeisolates from a tertiary care hospital in Mumbai during 2004–2013: a retrospective cross-sectional study

“…A similar finding has been reported globally 3738 The probable cause could be either due to spontaneous mutations or horizontal transfer of resistant genes within the gut flora and Vibrio species 37. The changing trend in antibiotic resistance over time may indicate the variability of treatment in the community.…”

Estimation of Vibrio Species Incidences and Antibiotic Resistance in Diarrhea Patients.

“…Incidences of Vibrio were found to be higher among adolescent and adult population, and similar observations were found in other report [38]. However, children <5 years age group (0-2 and 3-5 years) also suffered with similar infection rates as that of adult.…”

“…was seen throughout the years; however, slight peaks were observed during rainy, winter, and summer seasons. Similar seasonal trends have been observed from coastal area, but frequency is much higher as compared to current study [27,[37][38][39][40][41]. This may be due to lack of stagnant water reservoirs in the region and direct drainage of rain water into major river systems.…”

Correlation of the Native Inaba Strain With the Dominant Isolated Strains Obtained From Outbreaks in 2013 in Iran

“…2,24 On the other hand, the emergence of multidrug resistant V. cholera isolates has been reported frequently that is a major problem in developing coun-tries, particularly in Iran which is surrounded by several neighboring countries engaging with cholera problem. 25 The number of male cholera patients, their nationality, and the mean age all obviously confirmed the emergence of cholera from abroad. Regarding above mentioned issue, performing an active surveillance program at least during summer for all passengers from Afghanistan and Pakistan is recommended.…”