High-risk human papillomavirus cervical infection prevalence in France, 2020-2023: a nationwide, large-scale, and spatially resolved study comparing opportunistic and organised screening

Background: Since 2020, in France, cervical cancer screening among females aged 30 to 65 years has focused on the detection of high-risk human papillomaviruses (HR HPVs) cervical infection. All females within this age range who do not follow current screening recommendations are actively invited to perform an HPV test through an organised screening program. This represents a novel opportunity to study the prevalence of HR HPV cervical infection at a national level with high spatial resolution. Methods: The analytic sample contained 362,963 results of HPV tests performed on cervical samples collected on females aged 30 to 66 years, between 2020 and 2023, in Metropolitan France. These tests were performed through either the organised screening program or following spontaneous, i.e. 'opportunistic', screening. A full Bayesian bivariate model involving multiple Gaussian Markov random fields was used to get spatially resolved prevalence maps of HPV cervical infection caused by HPV16 and/or HPV18 (HPV16/HPV18) or caused by at least one of 12 other carcinogenic genotypes (31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68), correcting from the possible systematic inflation associated with opportunistic screening. Results: A raw description of the data found that 3.7% of tests were positive for HPV16/18 while 9.2% were positive for other high risk genotypes. Among samples collected through organised screening, 2.9% were positive for HPV16/18 and 6.9% for the other group of genotypes, against 3.8% and 9.4%, respectively, for samples collected through opportunistic screening. As of November 2023, among females aged 30 years, a very likely (probability > 0.95) systematic upward inflation in expected prevalence for opportunistic screening, with respect to organised screening, was found in 89.5% and 100.0% of postcodes for HPV16/18 and other genotypes, respectively. For Paris, France's capital city, this systematic upward inflation went from a posterior average [equal-tailed interval at 95%] of 1.9 [0.4,3.3] percentage points (pp), at 30 years old, to 1.0 [-0.1,1.9] pp at 66 years old for HPV16/18 and from 9.2 [5.7,12.7] pp to 2.7 [0.4,4.8] pp for other genotypes. The expected prevalence in the analytic sample, corrected for the systematic upward inflation associated with opportunistic screening, were 3.2 [2.9,3.6]% for HPV16/18 and 7.3 [6.7,7.9]% for other genotypes. Limits: Screening uptake within the organised screening program is subject to selection. Implication: The study provides the first spatially resolved picture of HR HPV cervical infection prevalence in France. The analysis highlights that opportunistic screening might be associated with a substantial systematic upward inflation in HPV cervical infection prevalence, compared with organised screening, which should be accounted for in prospective modelling studies.