Precision of the Kalon Herpes Simplex Virus Type 2 IgG ELISA : an international inter-laboratory assessment

CITATION: Patel, Eshan U., et al. 2015. Precision of the Kalon Herpes Simplex Virus Type 2 IgG ELISA : an international inter-laboratory assessment. BMC Infectious Diseases, 15:398, doi:10.1186/s12879-015-1130-6.The original publication is available at http://bmcinfectdis.biomedcentral.comBackground: The commercial Kalon HSV-2 IgG ELISA is currently recommended for research use in sub-Saharan Africa because of its superior accuracy compared to other serologic assays. However, there are no data on key precision parameters of Kalon such as inter-operator variation, repeatability, and reproducibility, thus contributing to a barrier for its acceptance and use in clinical trials in sub-Saharan Africa. We evaluated the analytical and field precision of the Kalon HSV-2 IgG ELISA. Methods: A total of 600 HIV-infected and uninfected serum samples from South Africa and Zambia, previously tested by the gold standard University of Washington HSV western blot (UW-WB), were tested using Kalon by two technologists in an United States reference laboratory. Aliquots of 183 samples were retested using Kalon by an on-site technologist in a South African laboratory and a Zambian laboratory. Results: Intra-assay variation was below 10 %. Intra-assay, intra-laboratory, and inter-laboratory correlation and agreement were significantly high (p < 0.01). In comparison to the UW-WB, accurate performance of Kalon was reproducible by each operator and laboratory. Receiver operating characteristic curve analysis indicated high selectivity of Kalon in the overall study population (area under the curve = 0.95, 95%CI = 0.92–0.97). Discussion: Kalon is a robust assay with high precision and reproducibility. Accordingly, operator errorlikely does not contribute to the variability observed in Kalon’s specificity throughout sera from sub-Saharan Africa. Conclusions: In populations with optimal diagnostic accuracy, Kalon is a reliable stand-alone method for on-site HSV-2 IgG antibody detection.http://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-015-1130-6Publisher's versio

HIV shedding from male circumcision wounds in HIV-infected men: a prospective cohort study.

BackgroundA randomized trial of voluntary medical male circumcision (MC) of HIV-infected men reported increased HIV transmission to female partners among men who resumed sexual intercourse prior to wound healing. We conducted a prospective observational study to assess penile HIV shedding after MC.Methods and findingsHIV shedding was evaluated among 223 HIV-infected men (183 self-reported not receiving antiretroviral therapy [ART], 11 self-reported receiving ART and had a detectable plasma viral load [VL], and 29 self-reported receiving ART and had an undetectable plasma VL [ 50,000 copies/ml than among those with an HIV plasma VL ConclusionPenile HIV shedding is significantly reduced after healing of MC wounds. Lower plasma VL is associated with decreased frequency and quantity of HIV shedding from MC wounds. Starting ART prior to MC should be considered to reduce male-to-female HIV transmission risk. Research is needed to assess the time on ART required to decrease shedding, and the acceptability and feasibility of initiating ART at the time of MC

Study flow diagram.

<p>The retention (asterisk) indicates the number (percent) of men at each follow-up visit.</p

Associations with the detection of penile HIV shedding.

<p>*Adjusted analysis included the following variables: treatment with co-trimoxazole, certified healed wound, HIV shedding prior to MC, baseline CD4 count, and plasma VL. Resumption of sexual intercourse and self-reported ART status were not included in the adjusted analysis because of co-linearity with certified wound healing and plasma VL, respectively.</p><p>^†There were 18 visits (1.4%) with missing wound-healing information, 31 visits with missing information on resumption of sexual intercourse, and 56 visits (4.7%) with missing plasma VL data. The adjusted analysis was a complete case analysis and included 98.5% of observed visits after MC (1,178/1,196).</p><p>Associations with the detection of penile HIV shedding.</p

Enrollment characteristics.

<p>Data are given as number (percent) or median (IQR).</p><p>^{^}<i>p</i>-Values compare self-reported not on ART, self-reported on ART with detectable VL, and self-reported on ART with undetectable VL.</p><p>*Assessed only among sexually active men. Data were also missing for five individuals in the no ART group.</p><p>Enrollment characteristics.</p