Concurrent infection with multiple human papillomavirus types among unvaccinated and vaccinated 17-year-old Norwegian girls
Menée en Norvège à partir d'échantillons d'urine collectés auprès de 10 149 filles de 17 ans et testés pour 37 génotypes du papillomavirus humain (HPV), cette étude analyse la présence d'infections concomitantes par différents types de HPV en fonction du statut vaccinal
Whether type-specific human papillomavirus (HPV) infection influences the risk of acquiring infections with other HPV types is unclear. We studied concurrent HPV infections in 17-year-old girls from two birth cohorts; the first vaccine-eligible cohort in Norway and a pre-vaccination cohort.Urine samples were collected and tested for 37 HPV genotypes. This study was restricted to unvaccinated girls from the pre-vaccination cohort (n=5245) and vaccinated girls from the vaccine-eligible cohort (n=4904). Risk of HPV infection was modelled using mixed-effect logistic regression. Expected frequencies of concurrent infection with each pairwise combination of the vaccine types and high-risk types (6/11/16/18/31/33/35/39/45/51/52/56/58/59) were compared to observed frequencies.Infection with multiple HPV types was more common among unvaccinated girls than vaccinated girls (9.2% vs. 3.7%). HPV33 and HPV51 was the only HPV-pair that was detected together more often than expected among both unvaccinated (p=0.002) and vaccinated girls (p<0.001). No HPV-pairs were observed significantly less often than expected.HPV33 and HPV51 tended to be involved in co-infection among both unvaccinated and vaccinated girls. The introduction of HPV vaccination does not seem to have had an effect on the tendency of specific HPV types to cluster together.