Human Papilloma Virus (HPV) prevalence and genotype distribution among women in Karachi, Pakistan

Human papillomavirus (HPV) epidemiological data from Pakistan remain limited, particularly in unscreened and unvaccinated populations. We performed a cross-sectional study in Karachi, Pakistan, to determine overall type- and age-specific HPV prevalence between May 2022 and November 2023. A total of 3119 women were invited to participate; 497 women gave consent, provided cervical samples and were included in the final analysis. HPV detection and genotyping were done using the highly sensitive INNO-LiPA HPV Genotyping Extra II line probe assay. Overall HPV prevalence was 16.7%. High-risk (HR) HPV types (counted once per genotype within IARC groups 1, 2A and 2B) were detected in 11.8% of women, and low-risk or unclassified types in 5.0%. Single HR-HPV infections occurred in 8.4% and multiple HR-HPV infections in 3.4%. Fourteen HR genotypes were detected as single infections, with HPV31 and HPV53 (1.2% each) being most prevalent, followed by HPV68 (1.0%), HPV16 (0.8%), and HPV33/HPV39/HPV51 (0.6% each). Less frequent types included HPV82 and HPV18 (0.4% each), and HPV35/HPV70/HPV73 (0.2% each). The most prevalent low-risk type was HPV6 (1.2%). HPV prevalence peaked in women aged 25-34 years (21.4%) and remained detectable in women above 54 years (12.5%). These data indicate a substantial and genetically diverse HR-HPV burden in Karachi. They support organized HPV-based cervical cancer screening using high-performance assays that detect the full panel of carcinogenic HPV types, with adequate triage and follow-up. They also support rapid scale-up and monitoring of HPV vaccination in Pakistan, including assessment of broader-valency vaccination strategies where feasible, to reduce cervical cancer, pre-cancerous lesions and other HPV-related cancers.