Changes in Cervical Cytology Results and Human Papillomavirus Types Among Persons Screened for Cervical Cancer, 2007 and 2015-2017.

OBJECTIVES: Since 2006, the US human papillomavirus (HPV) vaccination program has led to decreases in HPV infections caused by high-risk vaccine-targeted HPV types (HPV 16/18). We assessed differences in high-risk HPV prevalence by cervical cytology result among 20- to 24-year-old persons participating in routine cervical cancer screening in 2015-2017 compared with 2007. MATERIALS AND METHODS: Residual routine cervical cancer screening specimens were collected from 20- to 24-year-old members of 2 integrated healthcare delivery systems as part of a cross-sectional study and were tested for 37 HPV types. Cytology results and vaccination status (≥1 dose) were extracted from medical records. Cytology categories were normal, atypical squamous cells of undefined significance, low-grade squamous intraepithelial lesions (SIL), or high-grade SIL/atypical squamous cells cannot exclude high-grade SIL. Prevalences of HPV categories (HPV 16/18, HPV 31/33/45/52/58, HPV 35/39/51/56/59/66/68) were estimated by cytology result for 2007 and 2015-2017. RESULTS: Specimens from 2007 (n = 4046) were from unvaccinated participants; 4574 of 8442 specimens (54.2%) from 2015-2017 were from vaccinated participants. Overall, HPV 16/18 positivity was lower in 2015-2017 compared with 2007 in all groups: high-grade SIL/atypical squamous cells cannot exclude high-grade SIL, 16.0% vs 69.2%; low-grade SIL, 5.4% vs 40.1%; atypical squamous cells of undefined significance, 5.0% vs 25.6%; and normal, 1.3% vs 8.1%. Human papillomavirus 31/33/45/52/58 prevalence was stable for all cytology groups; HPV 35/39/51/56/59/66/68 prevalence increased among low-grade SIL specimens (53.9% to 65.2%) but remained stable in other groups. CONCLUSIONS: Prevalence of vaccine-targeted high-risk HPV types 16/18 was dramatically lower in 2015-2017 than 2007 across all cytology result groups while prevalence of other high-risk HPV types was mainly stable, supporting vaccine impact with no evidence of type replacement.

Reduction in Human Papillomavirus Vaccine Type Prevalence Among Young Women Screened for Cervical Cancer in an Integrated US Healthcare Delivery System in 2007 and 2012-2013.

BACKGROUND: In the United States, human papillomavirus (HPV) vaccine is recommended for 11- or 12-year-olds, and for young adults not previously vaccinated. Early vaccine impact can be measured by reductions in vaccine-type (VT) HPV prevalence. METHODS: Consecutive residual cervical specimens were retained from women aged 20-29 years at Kaiser Permanente Northwest in 2007, 2012, and 2013. HPV genotypes were determined using L1 consensus polymerase chain reaction with type-specific hybridization to detect 37 types, including VT HPV (HPV type 6, 11, 16, and 18). We compared HPV prevalence in 2007 and 2012-2013, and we evaluated predictors of VT HPV and any-HPV prevalence in 2012-2013. RESULTS: In 2012-2013, 31.9% of 4181 women had initiated HPV vaccination. VT HPV prevalence decreased from 10.6% in 2007 to 6.2% in 2012-2013 (P < .001). In 2012-2013, VT HPV prevalence was significantly lower among those who initiated vaccination <19 years (adjusted prevalence ratio, 0.1; 95% confidence interval, .1-.3) than among those who were not vaccinated, and higher among those who had chlamydia, human immunodeficiency virus, or pregnancy testing in the past year than among those who did not (adjusted prevalence ratio, 1.4; 95% confidence interval, 1.1-1.8). CONCLUSIONS: Reduction in VT HPV was found in young women in an integrated healthcare delivery system within 6 years of vaccine introduction, indicating early HPV vaccine impact.

Prevalence of HPV types in cervical specimens from an integrated healthcare delivery system: baseline assessment to measure HPV vaccine impact.

PURPOSE: Two human papillomavirus (HPV) vaccines are available to prevent cervical cancer. One early measure of HPV vaccine impact would be a reduction in vaccine-related HPV types (HPV 6, 11, 16, or 18, or HPV 16, 18) in cervical samples from young women. We aimed to assess feasibility of specimen collection and baseline HPV prevalence in an integrated healthcare delivery system. METHODS: Residual cervical specimens collected during routine cervical cancer screening (2006-2008) were retained consecutively from eligible females aged 11-29 years, stratified by age group. Specimens were evaluated for 37 HPV genotypes using the Roche Linear Array assay. RESULTS: Of 10,124 specimens submitted, 10,103 (99 %) were adequate for HPV testing. Prevalence of HPV 6, 11, 16, or 18 genotype was 11.4 % overall and was the highest in the youngest age group (18.1 % in the 11-19-year-olds, 12.5 % in the 20-24-year-olds, and 7.0 % in the 25-29-year-olds). CONCLUSIONS: HPV types 6, 11, 16, or 18 prevalence could be measured over time to assess early HPV vaccine impact using residual specimens from an integrated healthcare delivery system, particularly if sampling focused on young women.