Efficacies of prophylactic HPV vaccination for cervical abnormalities and each type of HPV infection in J-HERS 2021
None of the vaccinated patients had ASCH+ or HSIL+. Comparison with unvaccinated patients suggested that the prevalences of ASCH+ and HSIL+ (CIN2 or 3) had both decreased by 100% (Table 1). There was no significant difference in LSIL (CIN1), although a marginally decreased prevalence was observed for LSIL/ASCH+ (CIN1, 2) among vaccinated patients versus unvaccinated patients.
Regarding cervical HPV infection, the prevalences of HPV16 and HPV18 were 0.33% and 0.0%, respectively, among vaccinated patients, while those in unvaccinated were 6.6% and 2.7%, respectively (Fig. 2). This finding suggests that HPV vaccination reduced the prevalence of HPV16 by 95% (OR, 0.05; 95% CI, 0.0047–0.273; P < 0.0001) and HPV18 by 100% (OR, 0.00; 95% CI, 0.000–0.458; P = 0.0013) among vaccinated patients, compared with unvaccinated patients. The reduction rate of either HPV16 or HPV18 (i.e., HPV16/18) was 97% (OR, 0.03; 95% CI, 0.0034–0.191, P<0.0001). In contrast, the prevalences increased for HPV51 (OR, 2.14; 95% CI, 1.23–3.64; P = 0.0086) and HPV59 (OR, 3.73; 95% CI, 1.77–7.54; P = 0.0006) (Fig. 2A). However, there were no differences in other high-risk, probable high-risk, and low-risk HPV types (Fig.2B), including HPV6 and HPV11 (Fig.2A), which are the target types of the quadrivalent vaccine.
Among the different age groups, the prevalence of HPV16 significantly decreased in the 22- to 27-year and 28- to 33-year age groups after vaccination, whereas the prevalence of HPV18 infection decreased, but not significant in any age group (Fig. 3). The prevalence of HPV58 increased in the vaccinated 22- to 27-year age group (P = 0.0189), and the prevalence of HPV59 increased in the 28- to 33-year age group (P = 0.0025). No difference in the prevalences of HPV51 were observed in any age group.