Background: Few aspects of the occurrence of infections with multiple HPV types have been described. Since the immunity conferred by vaccines is type-specific, the epidemiology of such coinfections needs to be addressed.
Goal: The goal of the study was to document the prevalence and incidence of infection with multiple HPV types and the distribution of HPV types in coinfections.
Study design: In a prospective cohort of 2075 Brazilian women, cervical specimens were collected for cytology and HPV detection. Information on potential risk factors was obtained by interview.
Results: The prevalence of HPV coinfections was 3% among cytologically normal women, 10% among women with ASCUS, 23% among those with LSIL, and 7% among those with HSIL. The incidence rate of coinfection declined markedly with age (Ptrend<0.001). Some HPV types co-occurred less frequently than expected, namely, HPV 16 and 18 occurring with other oncogenic HPV types and HPV 6/11.
Conclusion: We have observed that occurrence of HPV coinfection was dependent both on age and on the presence of cytologic abnormalities. These results may have implications for vaccine development and for public health decisions about vaccination programs.