Laboratory surveillance of cholera in Nyanza province during the outbreak from April to July 2007

Cholera continues to be an important cause of morbidity and mortality in many areas of the world, and there is currently a high frequency of new outbreaks in Africa. Following a confirmed cholera outbreak in Siaya, Kisumu, Bondo and Nyando districts, Nyanza province in western Kenya between April and July 2007, a laboratory surveillance study was conducted at the New Nyanza Provincial General Hospital’s Microbiology Laboratory. The study aimed at isolating and identifying the strain of Vibrio cholerae, Identifying the mean age of the patients and monitoring the susceptibility patterns to major antibiotics. It further aimed at determining effectiveness of empiric management of cholera. A total of 219 samples were processed out of which a total of 85 samples (39%) were found positive for Vibrio cholerae 01 sero‐type Inaba. The mean age recorded was 19 years (1 ≤ 80). The modal ages recorded were 8, 20 and 25. 55% (47) of the recorded cases were females while 45% (38) were males. Generally, V.Cholerae 01 sero‐type Inaba showed antibiotic resistance to trimethoprim‐sulfamethoxazole, nalidixic acid, sulfasoxazole, streptomycin and furazolidone. Tetracycline a commonly used antibiotic for empiric management was 100% effective on all isolates and remains the drug of choice. Samples obtained for case‐control study did not yield any cholera isolate. No prior exposure to any antibiotic was recorded among all the subjects. The study confirmed the effectiveness of empirical therapy on cholera and further identified the need of proper hygiene, water treatment, proper waste management and proper eating habits as means of controlling morbidity and mortality of cholera.Key words: Cholera, morbidity, mortality, empiric management, antibiotic resistanc

Antimicrobial activity of Warbugia ugandensis against gramnegative multi‐drug resistant bacteria

The rise in antibiotic resistance has resulted in decreasing numbers of effective antimicrobial agents available to treat infections caused by multi‐drug resistant (MDR) bacteria. This has necessitated a search for new antimicrobial agents. Herbal remedies may offer alternative treatment options especially because they elicit little or no transferable resistance if used in optimal concentrations. This study evaluated the antimicrobial properties of W. ugandensis against eight multi drug resistant (MDR) Gram‐negative bacterial isolates. The herbal extracts were obtained using methanol as an organic solvent and water as an inorganic solvent. Determination of the Minimum Inhibitory Concentrations (MICs) and the sub‐lethal concentrations of the effective extracts was done using broth inoculation method followed by colony count. The test isolates were habituated in sub‐lethal extract concentrations (SLC) for 72 h to investigate effect on their sensitivity to conventional antibiotics. Methanol extracts from the root and stem‐bark of W. ugandensis were active against the test strains and their inhibitory effect was significantly different (p<0.05) from that of other extracts. We determined that the extracts had an inhibitory rather than a lytic (cidal) mode of action. The extracts from this plant had an effective MIC of 42 μg/ml and exhibited an inhibitory mode of action and did not elicit resistance to conventional antibiotics. Methanol extracts from the root and bark of this plant may provide potential sources for further development of alternative antimicrobial agents for the treatment of MDR infections.Key words: multi‐drug resistant (MDR) bacteria, minimum inhibitory concentrations (MICs), sub‐lethal concentration (SLC

Evaluation of an Antigen-Antibody “Combination” Enzyme Linked Immunosorbent Assay for Diagnosis of Hepatitis C Virus Infections

Background: Development of “combination” assays detecting in parallel, within a single test, Hepatitis C Virus (HCV) antigens and antibodies, not only reduces the window period in HCV-infection but also costs. Reduction of costs is important for developing countries where money and personal resources are limited.Methods: We compared the Monolisa® HCV Antigen-Antibody Ultra (Bio-Rad Laboratories Limited, Marnes La Coquette, France) with the AXSYM HCV version 3.0 (Abbot Diagnostics, Germany)-the latter assay detecting only antibodies to HCV. Seventy three HCV-PCR positive and negative samples were tested.Results: Although the two assays showed comparable results, two samples from a bone marrow transplant (BMT) patient of viral loads 7.8 x 105 and 8.9 x 106 IU/mL could not be detected by the Monolisa® HCV Antigen-Antibody Ultra assay. Failure to detect the two samples with viral loads considered above threshold of detection for antigen proteins suggested a lack of sensitivity by this assay to discover viral capsid protein in patient samples. Genotyping of these samples revealed genotype 1b, a HCV-subtype which is widespread and should thus be easily detected.Conclusion: We conclude that although this assay depicts high sensitivity and specificity in detecting antibodies to HCV, it seems not to add further benefit in our study population to detect HCV infections by enhanced sensitivity due the potential contingency to trace viral capsid antigens.Keywords: Ag-Ab Combination assay, Hepatitis C Virus, ELISA, Monolisa HCV Ag-Ab Ultr

Evaluation of an Antigen-Antibody “Combination” Enzyme Linked Immunosorbent Assay for Diagnosis of Hepatitis C Virus Infections

Background: Development of “combination” assays detecting in parallel, within a single test, Hepatitis C Virus (HCV) antigens and antibodies, not only reduces the window period in HCV-infection but also costs. Reduction of costs is important for developing countries where money and personal resources are limited.Methods: We compared the Monolisa® HCV Antigen-Antibody Ultra (Bio-Rad Laboratories Limited, Marnes La Coquette, France) with the AXSYM HCV version 3.0 (Abbot Diagnostics, Germany)-the latter assay detecting only antibodies to HCV. Seventy three HCV-PCR positive and negative samples were tested.Results: Although the two assays showed comparable results, two samples from a bone marrow transplant (BMT) patient of viral loads 7.8 x 105 and 8.9 x 106 IU/mL could not be detected by the Monolisa® HCV Antigen-Antibody Ultra assay. Failure to detect the two samples with viral loads considered above threshold of detection for antigen proteins suggested a lack of sensitivity by this assay to discover viral capsid protein in patient samples. Genotyping of these samples revealed genotype 1b, a HCV-subtype which is widespread and should thus be easily detected.Conclusion: We conclude that although this assay depicts high sensitivity and specificity in detecting antibodies to HCV, it seems not to add further benefit in our study population to detect HCV infections by enhanced sensitivity due the potential contingency to trace viral capsid antigens.Keywords: Ag-Ab Combination assay, Hepatitis C Virus, ELISA, Monolisa HCV Ag-Ab Ultr