Abstract and Introduction
Abstract
Background We performed a systematic review and meta-analysis to summarise the available data on the prevalence of human papillomavirus (HPV) among men in sub-Saharan Africa.
Methods PubMed and Embase were searched up to 10 March 2014. Random effects meta-analyses were used to calculate a pooled prevalence of any HPV and high-risk (HR) HPV.
Results A total of 11 studies comprising 9342 men were identified. We found that HPV is very common among men in sub-Saharan Africa, the prevalence of any HPV ranging between 19.1% and 100%. Using random effects meta-analysis, the pooled prevalence of any HPV was 78.2% (95% CI 54.2 to 91.6) among HIV-positive and 49.4% (95% CI 30.4 to 68.6) among HIV-negative men (p=0.0632). When restricting the analyses to PCR-based studies, the pooled prevalence of any HPV was 84.5% (95% CI 74.2 to 91.2) among HIV-positive and 56.4% (95% CI 49.7 to 62.9) among HIV-negative men (p<0.0001). Of the HPV types included in the nine-valent HPV vaccine, the most common HR HPV types were HPV16 and HPV52, and HPV6 was the most common low-risk HPV type. When examining the prevalence of HPV in relation to age no clear trend was observed.
Conclusions The prevalence of HPV is high among men in sub-Saharan Africa, which could contribute to the high rates of penile and cervical cancer in this part of the world. Implementation of the prophylactic HPV vaccines could potentially help prevent this large burden of HPV and HPV-associated disease in sub-Saharan Africa.
Introduction
Human papillomavirus (HPV) is the most common sexually transmitted infection. HPV is associated with cervical cancer in women, though it is increasingly recognised that HPV causes a substantial disease burden in men also, including genital warts, penile cancer, anal cancer and head-and-neck cancer. The prevalence of HPV and the burden of HPV-related cancers vary across populations. In sub-Saharan Africa, the rates of penile and cervical cancer are among the highest worldwide, which is possibly related to the high prevalence of both HPV and HIV, and also to the lack of effective screening programmes.
More than 120 types of HPV exist and these are divided into high-risk (HR) and low-risk (LR) types depending on their oncogenic potential. HPV16 and HPV18 are the most important HR HPV types accounting for the largest numbers of HPV-related cancers worldwide: HPV16 and HPV18 are the most common HPV types in penile cancer and cervical cancer and, furthermore, HPV16 is the most common HR HPV type detected in head-and-neck cancer. Two prophylactic vaccines against HPV have been developed: the quadrivalent HPV vaccine targeting HPV6/11/16/18 and the bivalent targeting HPV16/18. Furthermore, a nine-valent HPV vaccine targeting HPV6/11/16/18/31/33/45/52/58 is currently under development. The quadrivalent HPV vaccine has been shown to prevent HPV infection in men and to be highly immunogenic in HIV-positive men.
The large burden of HPV-related disease in sub-Saharan Africa underlines the importance of estimating the HPV prevalence in this region. Furthermore, this will increase the understanding of the natural history of HPV across populations. Previous reviews of HPV prevalence among men included only three studies or fewer from sub-Saharan Africa. We performed a systematic review and meta-analysis to summarise the available data on the overall, type-specific and age-specific prevalence of genital HPV DNA among men in sub-Saharan Africa.