Racial disparities in the prevalence of vaccine and non-vaccine HPV types and multiple HPV infection between Asia and Africa: A systematic review

Abstract

Background: Cervical Cancer is the 6th most common and 3rd most deadly cancer among women. Despite the fact that majority of the countries in Asia and Africa have similar economy and low life expectancy, the mean age standardized incidence rate (ASIR) of cervical cancer is substantially higher in Africa than Asia. Thus, this study aimed to identify the correlates of the higher ASIR rates in Africa relative to Asia. Methods: Peer-reviewed articles published between 2004 and 2017 were selected using the PRISMA standard. Sources of articles include Google Scholar, Scopus, PubMed Central, and EMBASE. Search keywords included: HPV genotypes, cervical cancer, HPV vaccine, and multiple infection in Africa and Asia. Result: A total of 29 and 17 full-length articles were selected from Africa and Asia respectively. Based on estimates in the general population, the incidence of high-risk HPV (hrHPV) types in Africa and Asia was 3.5 and 1.0 respectively. The prevalence of HPV infection was higher in Africa than in Asia (p< 0.001). The prevalence of HPV infection between 2004-2009 and 2010-2017 decreased in Africa but increased in Asia. More so, the prevalence of multiple HPV and non-vaccine HPV infection were higher in Africa than Asia (p< 0.001). The prevalent HPV types in Africa were HPV16, HPV18, and HPV52, while that of Asia were HPV16, HPV52, and HPV58, in descending order of prevalence. This study revealed that nonavalent HPV vaccine could prevent the development of 69.3% and 83.2% of HPV associated cervical abnormalities in Africa and Asia, respectively. Conclusion: This study revealed higher prevalence of HPV infection and multiple HPV infection in Africa compared with Asia, which could be responsible for the higher ASIR in Africa. It suggests that nonavalent vaccination including cervical screening using Pap smear could prevent over 90% of the cervical abnormalities in Africa.