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Genital herpes can be caused by two very similar viruses, herpes simplex virus (HSV)-1 or HSV-2. These two HSV types cannot be distinguished clinically, but genotyping is recommended in the first-episodes of genital herpes to guide counselling and management. Quantitative polymerase chain reaction (qPCR) is the preferred diagnostic method for HSV typing. However, commercial qPCR methods use expensive fluorescent labeled probes for detection. Furthermore, most low-cost methods are not able to differentiate between HSV-1 and -2. The aim of this study was to develop a high resolution melting (HRM) technology-based assay for sensitive HSV-1 and HSV-2 detection and genotyping. Using a panel of 46 clinical specimens, the performance of the HRM assay was compared to two commercial HSV tests: the HRM assay detected HSV in all 23 positive samples, with no false positive results (100% concordance with HSV I/II Real-TM assay). Additionally, the HRM assay correctly genotyped both HSV types in a subset of these clinical samples, as determined by the Realstar HSV PCR Kit. The HSV HRM assay provides a cost-effective alternative method to conventional more expensive assays and can be used in routine clinical specimens, in cases where it is particularly necessary to detect and distinguish HSV-1 from -2.

Cutaneous warts are infectious disorders caused by human papillomavirus (HPV). A recent study revealed that the HPV genotype influences the natural course and response to treatment for plantar warts, suggesting that HPV genotyping could potentially be used to optimize wart treatment schemes. For this purpose, a wart‐associated HPV genotyping assay was developed. The assay was subjected to an intensive validation process including, i.a., empiric determination of the annealing temperature, primer‐probe optimization, evaluation of the analytical specificity and sensitivity, viral load quantification, and qualitative as well as quantitative analysis of intra‐run repeatability and inter‐run reproducibility. The newly developed assay was employed in a small‐scale HPV genotyping study of wart biopsies (n = 50). The assay exhibited an analytical type‐specific sensitivity and specificity of 100% (95% confidence interval [CI]: 83.9%–100%). The limit of quantification of the tested sequences corresponded to less than 17 viral copies/µl, while the limit of detection was less than 5 copies/µl. Very good to excellent agreements were gained between intra‐ and inter‐run measurements (κ = 0.85–1.00) and coefficients of variation of the quantitative agreements were less then 3%. 22.5% (95% CI: 11%–39%) of the analyzed biopsies were negative for the tested HPV types, while 35% (95% CI: 21%–52%) contained multiple infections. The wart‐associated HPV quantitative polymerase chain reaction assay was proven to be highly sensitive and specific. Multiple HPV infections were detected in 35% of lesions, contradicting the current literature claiming that in immunocompetent patients only 4%–16% of warts exhibit multiple HPV infections. This assay is qualified to be implemented in development of future genotype specific wart treatment strategies.

Introduction. Studies on HPV prevalence in the head and neck region of South Africans are sparse. Of the available reports in the literature, there were no studies on the association between HPV-DNA presence in the mouth and oropharynx in relation to high-risk behaviours such as oral sex practice or tobacco and alcohol use. Materials and Methods. Following ethical clearance and informed consent, patients attending a regional HIV-management clinic and patients attending a dental hospital were recruited to this study. The participants completed an interview-based questionnaire obtaining demographic information, data on HIV serostatus, and behavioural data including sexual practices and tobacco and alcohol use, and a rinse-and-gargle specimen was taken. Specimens were analysed for HPV DNA on 3 separate PCR/qPCR platforms. Statistical analyses were performed for associations between the study group and categorical variables, HPV status, and data from the questionnaires. Results. Of 221 participants, 149 were from a general population and 72 from the HIV-management clinic. Smokers comprised 29.4% of the sample, and 45.2% of participants reported to have ever used alcohol. Open mouth kissing during teenage years was confirmed by 64.7% of participants, 40.3% have given oral sex with their mouth, and 44.8% confirmed to have received oral sex from their partner’s mouth. Seven participants (3.2%) had detectable α-HPV DNA, and 1 (0.4%) had detectable β-HPV DNA in their rinse-and-gargle specimens. Two participants were from the HIV-management clinic and 6 from the general dental population (overall 3.6%). Conclusion. Five high-risk HPV, 2 low-risk HPV, and one β-HPV types were detected. The low prevalence of 3.6% compares well to similar studies in different cohorts studied in South Africa and falls within the global oral/oropharyngeal prevalence spectrum. Only 4 participants, all from the HIV-management clinic, had palatine tonsils. No significant relationships were found between HPV presence and demographic data or sexual, oral sexual, tobacco use, or alcohol use, and no associations were seen with numbers of sexual and oral-sex partners.

Background: In previous years, several cutaneous disorders have been associated with human papillomavirus (HPV); however, the exact role of HPV remains largely unknown. The lack of optimization and standardization of the pre-analytical phase forms a major obstacle. The aim of this study was to develop an accurate/patient-friendly sampling method for skin disorders, with cutaneous warts as a case study. Methods: Various sample processing techniques, pre-treatment protocols and DNA extraction methods were evaluated. Several sampling methods were examined, that is, skin scrapings, swabs and a tape-based method. Quantification of DNA yield was achieved by beta-globin real-time polymerase chain reaction (qPCR), and a wart-associated HPV genotyping qPCR was used to determine the HPV prevalence. Results: All samples tested positive for beta-globin. Skin scrapings had significantly higher yield than both swab and tape-based methods ( p < 0.01), the latter two did not significantly differ from each other ( p > 0.05). No significant difference in DNA yield was found between cotton and flocked swabs ( p > 0.05). All swabs were HPV positive, and although there were some discrepancies in HPV prevalence between both swabs, an overall good strength of agreement was found [κ = 0.77, 95% CI (0.71–0.83)]. Conclusion: Although skin scrapings produced the highest DNA yield, patient discomfort was an important limitation of this method. Considering that in combination with our optimized DNA extraction procedure, all samples gave valid results with the less invasive swab methods preferred. Standardization of the pre-analytical phase is the first step in establishing a link between HPV and specific skin disorders and may have significant downstream diagnostic as well as therapeutic implications.