Prevalence and genotype distribution of HPV infection among 214,715 women from Southern China, 2012-2018: baseline surveys prior to mass HPV vaccination

Background : The epidemiology on the human papillomavirus (HPV) among females in Southern China is not well-established. Baseline data on the prevalence of HPV infection in China prior to mass prophylactic HPV vaccination would be useful. Thus, this study aimed to determine the type-specific HPV prevalence and distribution among females from Southern China prior to mass HPV vaccination.Methods : A retrospective cross-sectional study employing 214,715 women attending ChenZhou NO.1 People’s Hospital for cervical screening during 2012-2018 was conducted prior to widespread HPV vaccination. HPV genotype was detected using nucleic acid molecular diversion hybridization tests. The overall prevalence, age-specific prevalence, type distribution，and annual trend was analyzed.Results : The overall HPV prevalence was 18.71% (95% confidence interval [CI], 18.55%-18.88%) among Southern China females. During 2012–2018, the prevalence of HPV infection showed a downward tendency, from 21.63% (95% CI, 21.07%-22.20%) in 2012 to 18.75% (95% CI, 18.35%-19.16%) in 2018. Age-specific HPV distribution displayed a peak at young women aged less than 21 years (33.11%, 95% CI, 31.13%-35.15%), 20.07% ( 95% CI, 19.70%-20.44% ) among women aged 21-30 years, 17.29% (95% CI, 17.01%-17.57%) among women aged 31-40 years, 17.23% (95% CI, 16.95%-17.51%) among women aged 41-50 years, 21.65% (95% CI, 21.11%-22.20%) among women aged 51-60 years, and 25.95% (95% CI, 24.86%-27.07%) among women aged over 60 years. Of the 21 subtypes identified, the most three prevalent high-risk HPV (HR-HPV) genotypes were HPV52 (5.12%; 95% CI, 21.11%-22.20%), -16 (2.96%; 95% CI, 2.89%-3.03%), and -58 (2.51%; 95% CI, 2.44%-2.58%); the predominant low-risk HPV (LR-HPV) genotypes were HPV81 (1.86%; 95%CI, 1.80%-1.92%) and -6 (0.69%; 95% CI, 0.66%-0.73%) respectively. Incidence of HR-HPV only, LR-HPV only and mixed LR- and HR-HPV were 15.17%, 2.07% and 1.47% respectively. Besides, single HPV infection accounted for 77.30% of all positive cases in this study.Conclusions: This study highlights 1) a high prevalence of HPV infection among females with a decreasing tendency towards 2012-2018, especially for young women under the age of 21 prior to mass HPV vaccination; 2) HPV52, -16 and -58 were the predominant HPV genotypes, suggesting potential use of HPV vaccine covering these HPV genotypes in Southern China.