Molecular epidemiology of sexually transmitted human papillomavirus in a self referred group of women in Ireland.

BACKGROUND: Human papillomavirus (HPV) causes cervical cancer and external genital warts. The purpose of this study is to document the genotype distribution of HPV in females aged between 18 and 34 who self-referred to an STI clinic with visible external genital warts (EGW). Scrapings were taken from visible external genital warts (EGW). These scrapings were analysed by PCR for the presence of HPV DNA. Positive samples were then genotyped by means of a commercially available assay (LiPA). A comparison of genotyping results determined by the LiPA assay and direct amplicon DNA sequencing was also performed. RESULTS: Ninety-two patients out of 105 samples (88%) had detectable levels of HPV DNA. The majority of individuals with EGW (66%) showed the presence of two or more genotypes. The most common HPV genotypes present in the study population were HPV-6, HPV-11, HPV-16, HPV-18, HPV-33 and HPV-53. Potential effects of vaccination on HPV molecular epidemiology indicate that 40% of the patients could have been protected from the high risk genotypes HPV-16 and HPV-18. CONCLUSION: This is the first report of the molecular epidemiology of external genital warts in women aged between 18 and 34 from Ireland based on results from a LiPA assay. The study shows that most individuals are infected with multiple genotypes including those with high oncogenic potential and that the newly available HPV vaccines could have a significant impact on prevalence of the most common HPV genotypes in this study population.

Development of a real-time RT-PCR and Reverse Line probe Hybridisation assay for the routine detection and genotyping of Noroviruses in Ireland.

BACKGROUND: Noroviruses are the most common cause of non-bacterial gastroenteritis. Improved detection methods have seen a large increase in the number of human NoV genotypes in the last ten years. The objective of this study was to develop a fast method to detect, quantify and genotype positive NoV samples from Irish hospitals. RESULTS: A real-time RT-PCR assay and a Reverse Line Blot Hybridisation assay were developed based on the ORF1-ORF2 region. The sensitivity and reactivity of the two assays used was validated using a reference stool panel containing 14 NoV genotypes. The assays were then used to investigate two outbreaks of gastroenteritis in two Irish hospitals. 56 samples were screened for NoV using a real-time RT-PCR assay and 26 samples were found to be positive. Genotyping of these positive samples found that all positives belonged to the GII/4 variant of NoV. CONCLUSION: The combination of the Real-time assay and the reverse line blot hybridisation assay provided a fast and accurate method to investigate a NoV associated outbreak. It was concluded that the predominant genotype circulating in these Irish hospitals was GII/4 which has been associated with the majority of NoV outbreaks worldwide. The assays developed in this study are useful tools for investigating NoV infection.

The prevalence and genotype of human papillomavirus on cervical samples from an Irish female population with external genital warts.

The aim of this study was to determine the cervical genotype profile of females who presented to an STI Clinic with external genital warts (EGW); and to determine the potential vaccine coverage prior to the uptake of the HPV vaccines. Sixty-one cervical scrapings were taken from females aged 18-35 y who had external genital warts or a history of external genital warts. The resulting 50 samples that were positive for HPV-DNA were subjected to genotype identification. Forty-six of these samples had detectable genotypes by LIPA analysis and most (78%, 36/46) had multiple low risk (LR) and high risk (HR) genotypes on the cervix. Twenty-five of these samples (54%) had more than 1 HR genotype. Of the 36 patients who had any HR genotypes, 18 (50%) were identified to have the most oncogenic HPV genotypes, namely 16 and 18. Three of these samples had both 16 and 18 on the cervix. The presence of multiple HR genotypes on the majority of cervical samples from a self-referred population of females with EGW is presented. This study is of importance since persistent HR-HPV is the necessary risk factor in the development of precancerous and cancerous lesions of the cervix. Gardisil, the quadrivalent HPV vaccine would have been useful in the prevention of 28% (13/46) of these infections.