The investigators would like to estimate the prevalence of HPV infections based on cervical samples collected from the Sikkimese women aged 18 to 22 years at baseline (i.e. when the study participants are expected to have no benefit of vaccination) and seven years after the launch of the HPV vaccination programme, by which time the initial vaccinated cohorts will be aged 18 to 22 years and many of them will be sexually active. If the vaccination programme continues with the current high coverage rate, the cohort of women in the second age group are expected to be protected due to herd immunity, irrespective of whether any individual woman receives the vaccine or not. Overall effectiveness to protect women aged 18-22 years against targeted and non-targeted HPV infections will be monitored through repeated cervical sample -based surveys.
This project aims is to monitor the effectiveness of HPV vaccination in real-word conditions, at least 7 years after initiation of HPV vaccination in Sikkim. This study would give an opportunity to provide rapid feedback to the Indian public health authorities about the impact of the HPV vaccine.