Prevalence, incidence and persistence of genital HPV infections in a large cohort of sexually active young women in the Netherlands

Vaccine
Volume 31, Issue 2, Pages 279-438 (2 January 2013)
http://www.sciencedirect.com/science/journal/0264410X

Prevalence, incidence and persistence of genital HPV infections in a large cohort of sexually active young women in the Netherlands
Original Research Article
Pages 394-401
M. Mollers, J. Boot Hein, J. Vriend Henrike, J. King Audrey, V.F. van den Broek Ingrid, E.A.M. van Bergen Jan, A.T.P. Brink Antoinette, F.G. Wolffs Petra, J.P.A. Hoebe Christian, J.L.M. Meijer Chris, A.B. van der Sande Marianne, E. de Melker Hester

Abstract
Background
We assessed age- and type-specific HPV prevalence, incidence and persistence and their associated risk factors in young women prior to vaccination, to enable monitoring of the impact of introduction of HPV vaccination in the years before participation in the cervical screening program.

Methods
The HPV status was assessed in 3282 women aged 16–29 who participated in a Chlamydia trachomatis screening implementation program, of which 2014 women (61%) participated in two rounds (one year apart). Self-collected vaginal swab were analyzed by SPF10 LiPA on the presence of HPV DNA. Risk factors for prevalent, incident and persistent HPV infections were calculated using generalized estimating equation.

Results
The prevalence of any HPV in the first round amounted to 54%, while 34% of the women who participated in the second round had a persistent infection and 45% an incident infection. The five most common HPV types found in this study were HPV16, −51, −52, −31 and −53. HPV16 and/or HPV18 prevalence, incidence and persistence in the second round were 15%, 8% and 9%, respectively and for HPV6 and/or HPV11 6%, 4% and 2%, respectively. Relatively to other HPV genotypes, hrHPV types were found more often as a persistent infection than as an incident infection. Furthermore, there is an age-dependent increase within this age range for persistent infections but not for incident infections.

Conclusion
The HPV prevalence (54%), incidence (45%) and persistence (34%) is high among sexually active young women in the Netherlands. The different HPV type distribution and risk factors for prevalent, incident and persistent infections, as well as the observed age-trends should be taken into account in interpreting data obtained after vaccine introduction. Repeating measurements post-immunization are particularly relevant until the age when screening starts (i.e. 30 years in the Netherlands).