A molecular and epidemiological study of Vibrio cholerae isolates from cholera outbreaks in southern Ghana.

Cholera remains a major global public health threat and continuous emergence of new Vibrio cholerae strains is of major concern. We conducted a molecular epidemiological study to detect virulence markers and antimicrobial resistance patterns of V. cholerae isolates obtained from the 2012-2015 cholera outbreaks in Ghana. Archived clinical isolates obtained from the 2012, 2014 and 2015 cholera outbreaks in Ghana were revived by culture and subjected to microscopy, biochemical identification, serotyping, antibiotic susceptibility testing, molecular detection of distinct virulence factors and Multi-Locus Variable-Number of Tandem-Repeat Analysis (MLVA). Of 277 isolates analysed, 168 (60.6%) were confirmed to be V. cholerae and 109 (39.4%) isolates constituted other bacteria (Escherichia coli, Aeromonas sobria, Pseudomonas aeruginosa, Enterobacter cloacae and Enterococci faecalis). Serotyping the V. cholerae isolates identified 151 (89.9%) as Ogawa, 3 (1.8%) as Inaba and 14 (8.3%) as non-O1/O139 serogroup. The O1 serogroup isolates (154/168, 91.7%) carried the cholera toxin ctxB gene as detected by PCR. Additional virulence genes detected include zot, tcpA, ace, rtxC, toxR, rtxA, tcpP, hlyA and tagA. The most common and rare virulence factors detected among the isolates were rtxC (165 isolates) and tcpP (50 isolates) respectively. All isolates from 2014 and 2015 were multidrug resistant against the selected antibiotics. MLVA differentiated the isolates into 2 large unique clones A and B, with each predominating in a particular year. Spatial analysis showed clustering of most isolates at Ablekuma sub-district. Identification of several virulence genes among the two different genotypes of V. cholerae isolates and resistance to first- and second-line antibiotics, calls for scaleup of preventive strategies to reduce transmission, and strengthening of public health laboratories for rapid antimicrobial susceptibility testing to guide accurate treatment. Our findings support the current WHO licensed cholera vaccines which include both O1 Inaba and Ogawa serotypes.

Chlamydia Trachomatis and Neisseria Gonorrhoeae prevalence among women of reproductive age living in urogenital schistosomiasis endemic area in Ghana.

BACKGROUND: Many studies have shown an overlap in the epidemiology of sexually transmitted infections (STIs) and urogenital schistosomiasis among young women living in schistosomiasis endemic areas. Yet we found no study assessing the prevalence of STI infections in urogenital schistosomiasis endemic areas in Ghana. As part of an epidemiological study on urogenital schistosomiasis and HIV, we sought to assess the prevalence of both Chlamydia trachomatis (CT) and Neisseria gonorhoeae (NG) infections among women living in schistosomiasis endemic communities and explore the relationship between the sexually transmitted infections (STIs) and demographic characteristics, sexual behaviour and self-reported symptoms. METHODS: This was a cross-sectional study in which endocervical samples were collected from 191 women aged 15-49 years from October 2005 to March 2006. Samples were examined for CT and NG using Polymerase Chain Reaction (PCR). A structured questionnaire was also used to elicit information on study participant's gynaecological and obstetric history and symptoms for genital infection. Chi-square test and binary logistic regression were used to assess association between CT and NG and other variables such as age, sexual behaviour and self-reported symptoms. RESULTS: The overall prevalence of CT and NG were 6.3% and 2.6% respectively.The highest prevalence rates of CT were in the 15 to 19 year group while only individuals between 15 and 39 years were positive for NG. There was no association between CT and age, contraceptive use and the other variables assessed. NG on the other hand was found to be associated with age, number of births and number of sexual partners only by chi-square test. CONCLUSIONS: Our research revealed higher prevalence of CT and NG infections when compared to previous studies conducted among higher risk groups in non-urogenital schistosomiasis areas in Ghana. We therefore recommend further studies of these STIs in urogenital schistosomiasis endemic areas in the country.