{"entity":{"id":"paper-machalek-hpv-vaccine-impact-south-africa-lancet-glob-health-2026","kind":"paper","name":"Population impact of South Africa's human papillomavirus (HPV) vaccination programme on HPV prevalence in adolescent girls with and without HIV: a repeat cross-sectional study","aka":[],"tldr":"Infection with the two virus types that cause most cervical cancer fell by 83 per cent among 17 and 18 year old South African girls after the school vaccination programme, and by a similar proportion among girls living with HIV.","summary":"South Africa began vaccinating Grade 4 girls aged 9 and over at school against HPV types 16 and 18 in 2014, reaching 87 per cent of learners with at least one of two doses. The authors invited girls aged 17 to 18 from 15 primary care clinics in Free State, Gauteng, Mpumalanga and North West to give a self-collected vaginal sample: 819 in 2019, before the vaccinated cohorts reached that age, and 1,538 in 2023, from cohorts eligible for the programme.","asOf":"2026-11-04","links":[{"label":"Lancet Glob Health 2026","url":"https://doi.org/10.1016/S2214-109X(25)00525-X"},{"label":"PubMed","url":"https://pubmed.ncbi.nlm.nih.gov/41856140/"}],"tags":[],"related":[],"cancers":["cervical"],"sections":[],"technologies":["hpv-vaccine"],"targets":[],"drugs":[],"companies":[],"institutions":["south-africa-national-department-of-health"],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"journal":"Lancet Global Health","year":2026,"doi":"10.1016/S2214-109X(25)00525-X","pmid":"41856140","authors":"Machalek DA, Nyemba DC, Travill D, Petoumenos K, Mbulawa ZZA, Naidoo I, Motshwane FMM, Bamford L, Rees H, Kaldor JM, Delany-Moretlwe S, HOPE study group","paperType":"observational","findings":["HPV 16 or 18 prevalence fell from 21.6% (177 of 819) before to 3.2% (49 of 1,538) after, an adjusted prevalence ratio of 0.17 (95% CI 0.12 to 0.24).","Among girls living with HIV it fell from 29.4% (73 of 248) to 4.4% (13 of 295), adjusted prevalence ratio 0.18 (0.10 to 0.32).","Other HPV types did not fall significantly, except types 31 and 45, consistent with cross-protection."],"whatItMeans":"A two-dose school programme in a country with high HIV prevalence produced reductions in infection similar to three-dose programmes in high-income countries, including in girls living with HIV, who are at higher risk of cervical cancer.","caveats":["It measures infection, not cancer; the effect on cervical cancer will take years to appear.","Two cross-sectional surveys in four provinces; vaccination status came from registers and self-report."],"participants":2357},"route":"/key-papers/paper-machalek-hpv-vaccine-impact-south-africa-lancet-glob-health-2026/","neighbours":{"cancer":[{"id":"cervical","kind":"cancer","name":"Cervical cancer","route":"/cancers/cervical/"}],"technology":[{"id":"hpv-vaccine","kind":"technology","name":"HPV & HBV vaccination","route":"/technologies/hpv-vaccine/"}],"institution":[{"id":"south-africa-national-department-of-health","kind":"institution","name":"National Department of Health, South Africa","route":"/institutions/south-africa-national-department-of-health/"}]}}