Prevalence and genotype distribution of high risk human papillomavirus among HIV infected and uninfected women in Harare, Zimbabwe

Abstract

Introduction: High-risk Human Papilloma viruses (hr-HPVs) are one of the most important causative agents of cervical cancer. Genotype testing for hr-HPV DNA is a valuable cervical cancer screening tool.  It is used for the determination of HPV prevalence and subtype distribution, which are useful in evaluating the impact of HPV vaccines and possibly policy formulation for national cervical cancer vaccination programs.

Objective: This study aimed to determine the prevalence and distribution of hr-HPV genotypes and their association with cytology amongst HIV-positive and negative women in Harare, Zimbabwe.

Design and Setting: A cross-sectional study was conducted between 2017 and 2019 among HIV-infected and uninfected Zimbabwean women who presented for cervical cancer screening at the Family Planning Clinic at Parirenyatwa Hospital, Harare. Nurses obtained the cervical samples and Liquid-Based Cytology and hr-HPV DNA testing were performed using automated BD SurePathTM liquid based Pap test and Cepheid GeneXpert (Sunnyvale, California) respectively.

Subjects:  Two hundred and twenty-eight (228) women were enrolled in to the study and47.8% were HIV-infected. The participants were selected randomly as they walked into the clinic and were not necessarily indisposed. The median age was 40 years and 39 years for HIV-infected and HIV-uninfected participants, respectively.

Results:  The overall prevalence of hr-HPV was 41.1% with higher prevalence observed in HIV-infected (57.9%) when compared to HIV-uninfected women (25.6%), p=<0.001. Multiple hr-HPV infections were higher in HIV-infected (16.0%) than HIV-uninfected (4.3%) women, p=<0.001. The most common types were hr-HPV 16 and hr-HPV 18/45, with each exclusively observed in 12.0.9% and 15.2% of infections respectively. About48.9% of women infected by hr-HPV “other” had at least one type of hr-HPV type not covered by the bivalent vaccine. This category included 64.4% of HIV-infected and 35.5% of HIV-uninfected women. The prevalence of hr-HPV increased with the severity of the cytological lesions. In HIV-infected women, the hr-HPV prevalence was 44.8% in ASCUS, 74.1% in LSIL and 84.6% in HSIL/ASC-H, while in HIV-uninfected women it was 15.4% in ASCUS, 37.9 % in LSIL and 55.0% in HSIL/ASC-H (p=<0.001).

Conclusion:  In both HIV infected and uninfected groups, HPV infection peaked in middle-aged women (30 to 40 years). However, hr-HPV infection increased with age in HIV-infectedwomen and decreased with age in HIV-uninfected women. The hr-HPV prevalence was two times higher among HIV-infected than uninfected women with the prevalence increasing with severity of cytological lesions in both HIV-infected and uninfected women.  Infection with multiple hr-HPV types and a strong association between abnormal cytology and HIV infection was observed.  Other hr-HPV types besides types 16 and 18/45 were also prevalent in significant proportions. Further investigation is recommended to ascertain the cross protection of the cervical cancer vaccine available in Zimbabwe against the high-risk types other than 16 and 18/45. We also recommend a more systematic approach to hr-HPV data collection for a successful cervical cancer prevention program.