Multiple-type human papillomavirus (HPV) infections: A cross-sectional analysis of the prevalence of specific types in 309,000 women referred for HPV testing at the time of cervical cytology

Objectives: To determine the frequency of multiple-type cervical human papillomavirus (HPV) infections, and whether any types are involved in multiple-type infections more or less frequently than might be expected if these infections occur randomly. Methods: In this retrospective analysis of type-specific HPV testing, results from women 18 to 65 years old with samples collected between July 2007 and May 2011 were considered. Multivariate logistic regression analysis was used to model the presence of each of the 24 most prevalent HPV types, adjusting for one other HPV type, age, laboratory region, and age-by-region interactions. Results: Human papillomavirus infection was present in 74,543 (24.1%) of 309,471 women and 65,492 (21.1%) were positive for one of the top 24 most prevalent HPV types. The most common HPV type was type 16, occurring in 4.1% of the entire sample. A total of 14,181 women were positive for 2 or more HPV types (4.6% of entire sample and 19.0% of HPV-positive sample). Two-way HPV type comparisons were analyzed. Types 52, 53, 81, and 83 were more likely to occur in multiple infections with other types; and types 16, 58, and 66 were less likely to occur in multiple infections with other types. Human papillomavirus types 72 and 81 have the strongest positive relationship (odds ratio, 5.2; 95% confidence interval, 3.6Y7.4). Human papillomavirus types 33 and 66 have the strongest negative relationship (odds ratio, 0.4; 95% confidence interval, 0.2Y0.6). Conclusions: In this population, multiple-type HPV infections were present in 4.6% of all women. Our findings suggest that there may be both competitive and cooperative interactions between HPV types.