BACKGROUND AND PURPOSE:

• Drolet et al. (The Lancet, 2019) have updated and quantified the impact of multiple age-cohort HPV vaccination

METHODS:

• Updated systematic review and meta-analysis
•  Population-level impacts of vaccination on following endpoints
  • Genital HPV infections
  • CIN2+
• Time parameters
  • Publications on the topic between Feb 1, 2014, and Oct 11, 2018
• Inclusion criteria
  • Pre and post vaccination frequency (prevalence or incidence) comparisons of ≥1 HPV-related endpoint
  • Same population sources and recruitment methods before and after vaccination
• Data analysis
  • Relative risk (RR) compared the frequency of HPV-related endpoints between the pre-vaccination and post-vaccination periods
  • Analyses were stratified by: Sex | Age | Years since introduction of HPV vaccination

RESULTS:

• 65 articles in 14 high-income countries
  • 23 for HPV infection | 29 for anogenital warts | 13 for CIN2+
  • >60 million individuals over 8 years (2007-2015)

After 5–8 years of vaccination – among females

• HPV 16 and 18: Prevalence decreased significantly
  • 13-19 years: 83% reduction (RR 0.17, 95% CI, 0.11–0.25)
  • 20-24 years: 66% reduction (RR 0.34, 95% CI, 0.23–0.49)
• HPV 31, 33, and 45: Prevalence decreased significantly
  • 13–19 years: 54% reduction (RR 0.46, 95% CI, 0.33–0.66)
• Anogenital warts: Diagnoses decreased significantly
  • 15–19 years:  67% reduction (RR 0.33, 95% CI, 0.24–0.46)
  • 20–24 years: 54% reduction (RR 0.46, 95% CI, 0.36–0.60)
  • 25–29 years: 31% reduction (RR 0.69, 95% CI, 0.53–0.89)

After 5–8 years of vaccination – among males

• Anogenital warts: Diagnoses decreased significantly
  • 15-19 years: 48% reduction (RR 0.52, 95% CI, 0.37–0.75)
  • 20-24 years: 32% reduction (RR 0.68, 95% CI, 0.47–0.98)
• After 5–9 years of vaccination, CIN2+ decreased significantly
  • 15–19 years: 51% reduction (RR 0.49, 95% CI, 0.42–0.58)
  • 20–24 years: 31% reduction (RR 0.69, 95% CI, 0.57–0.84)
  • For the first 5 years following vaccination, significant decrease in CIN2+ was noted only in the screened girls (15-19 years)
• Multi-cohort programs with high HPV vaccination coverage had a greater direct impact and herd effects

CONCLUSION:

• Evidence shows considerable beneficial impact of HPV vaccination on
  • HPV infections and CIN2+ among girls and women
  • anogenital warts diagnoses among girls, women, boys, and men

Learn More – Primary Sources:

Population-level impact and herd effects following the introduction of human papillomavirus vaccination programmes: updated systematic review and meta-analysis

Related ObG Topics:

HPV Vaccine Recommendations Including 2-Dose Regimen for Younger Adolescents

HPV Vaccines: Cochrane Reviews Looks at the Evidence with Multi-Year Follow-Up

HPV Testing vs PAP Smear: Results of the HPV FOCAL Trial

The HPV Vaccine Leads to a Reduction in Cervical Precancers in Young Women in the U.S.