It has been shown that vaccination of HPV naive women against HPV 6/11 protects sufficiently from genital warts and may even lead to protection of non-vaccinated men and women in the same population. However it is uncertain what level of vaccine coverage is needed for such cohort effects
WOLVES (Wolfsburg HPV epidemiological study) invited all women born 1983/84 and 1988/89 with a first residency in Wolfsburg to participate in 2009/10. Participants born 1988/89 with a first residency in Wolfsburg to participate in 2009/10. Participants born 1988/89 were followed with annual examinations from 2009/10 till 2014/15. Women born 1993/94 were first invited 2014/15 and are followed with annual visits.HPV-testing is based on LR and HR-HC2 followed by HPV genotyping with SPF-10 PCR of all HC2 positive and 10% of HC2 negative samples.
Between Oct 2009 and Dec 2015 , 2,360 women were recruited. The HPV vaccination coverage rate rose from 6.1% among 26 years old women in 2010 to 18.4% in 2015 while the corresponding rates for 21 years old women increased from 23.7 to 48.2%. Simultaneously the life risk to suffer from at least one episode of genital warts before age 27 dropped from 4.7% in 2010 to 2.5% in 2015 while the life risk before age 22 declined from 1.8% to 0.4%. This trend of disapperance of genital warts was underlined by a decline in the prevalence of HPV 6 from 2.1% to 0.2% among 26 years old women between 2010 and 2015 and from 2.0% to 0.0% among 21 years old women.
The unexpected significant drop in genital warts and HPV 6 prevalence in a population with suboptimal HPV vaccine coverage is reassuring . Obviously the transmission of HPV as the causal agent of most genital warts is strongly inhibited even in populations with low vaccination covrage.