Phenotypic and genotypic characteristics of Vibrio cholerae O1 isolated from the Sierra Leone cholera outbreak in 2012.

BACKGROUND: This study describes phenotypic, genotypic and antibiotic susceptibility patterns of the strains isolated from the 2012 Sierra Leone cholera outbreak. Rectal swabs were collected from patients and cultured for Vibrio cholerae O1. METHODS: The isolates were subjected to multiplex PCR, mismatch amplification mutation assay (MAMA) PCR, pulsed field gel electrophoresis (PFGE), and antibiotic sensitivity tests using disk diffusion and minimum inhibitory concentration (MIC) E-test following standard procedures. RESULTS: Out of 17 rectal swabs tested, 15 yielded V. cholerae O1 biotype El Tor, serotype Ogawa. All the strains belonged to 'altered' variants as MAMA PCR result showed the presence of classical cholera toxin B. PFGE result revealed four pulse types. Using antibiotic disk diffusion, all the isolates were resistant to erythromycin, chloramphenicol, furazolidone, and trimethoprim/sulfamethoxazole (SXT) except SL1 which was sensitive to chloramphenicol and SXT. All the isolates were sensitive to nalidixic acid, tetracycline, doxycycline, azithromycin, and ciprofloxacin except SL2 which was resistant to nalidixic acid. However, variable sensitivity patterns were observed for kanamycin. The ranges of MIC were 0.125-0.50 mg/l, 0.003-0.023 mg/l and 0.38-0.75 mg/l for azithromycin, ciprofloxacin and tetracycline, respectively. CONCLUSIONS: This study demonstrates that altered variants of V. cholerae O1 of four clonal types were responsible for the 2012 outbreak of cholera in Sierra Leone.

Phenotypic, genotypic, and antibiotic sensitivity patterns of strains isolated from the cholera epidemic in Zimbabwe.

This paper details the phenotypic, genotypic, and antibiotic sensitivity patterns of 88 Vibrio cholerae strains from Zimbabwe. Of the 88 strains, 83 were classified as "altered El Tor" and 5 as "hybrid El Tor" strains. All of the strains were susceptible to tetracycline, doxycycline, ciprofloxacin, and azithromycin by disc diffusion, but susceptibility to tetracycline and azithromycin diminished when observed using the MIC method.

Programmatic aspects of dropouts in child vaccination in Bangladesh: findings from a prospective study.

The present study investigated prospectively programmatic factors relating to dropouts in child vaccination in 6 subdistricts of Bangladesh. A cross-sectional survey (n = 2700) was conducted estimating overall coverage of immunization using cluster sampling. The eligible subsample of children (n = 1064) was followed up prospectively to understand reasons for dropouts. In-depth interviews (n = 73) with mothers/caregivers and service providers were done and EPI (Expanded Programme on Immunization) sessions were observed (n = 131). Irregular EPI sessions were the prime cause of dropouts particularly in low-performing subdistricts. The other programmatic factors linked with dropouts were (a) no reminder about subsequent session/doses, (b) unfriendly behavior or absence of vaccinator, ( c) refusal due to lost card or vaccine exhausted, and (d) short duration of sessions. Providers highlighted constraints such as financial problems for transportation, particularly in the hard-to-reach areas and vacancies of the posts of health assistants. The barriers to completing full schedules of vaccination can be removed to a large extent through programmatic adjustments.