Human papillomavirus genotype distribution patterns in Zimbabwe; is the bivalent vaccine sufficient?

BACKGROUND: Vaccination against Human papillomavirus (HPV) is the primary preventative strategy that has been shown to reduce the burden of HPV related diseases. Zimbabwe introduced the bivalent vaccine (HPV 16/18) in the vaccination program targeting prepubescent girls in 2018. This review is an analysis of the distribution of HPV genotypes from various studies conducted in Zimbabwe to ascertain the effectiveness of the bivalent vaccine and make recommendations for future HPV vaccine choices.

SUMMARY: Zimbabwean studies have mostly reported on cervical HPV in the urban areas. The most frequent HPV genotypes from cervical sites were 16, 18, 33, 35, 45, 56 and 58. These were identified from samples with normal cytology, pre-cancer and invasive cervical cancer. The few studies that have been done in rural areas reported HPV 35 as the most frequent cervicovaginal genotype. From the anal region of individuals reporting for routine screening, HPV 16, 18, 35 52 and 58 were the most frequent. A study on genital warts identified HPV 6, 11, 16, 40, 51and 54. In a study on children with recurrent respiratory papillomatosis (RRP), HPV 6 and 11 were the most common and HPV 35 was also identified in these children. There is no available published data on HPV distribution in head and neck cancers in Zimbabwe.

KEY MESSAGES: Given that 83% of cervical cancers in Zimbabwe are caused by HPV 16/18, the bivalent vaccine could cover a significant proportion of HPV related cervical cancer. The current limitation of the bivalent vaccine is its failure to prevent benign lesions such as genital warts and RRP or all cervical cancer cases in Zimbabwe. For the prevention of most HPV related conditions, the nonavalent vaccine would be the most appropriate option for the Zimbabwean population. Currently there is no vaccine that includes HPV 35, yet this genotype was frequently identified in HPV related diseases. Vaccine developers may need to consider HPV 35 when manufacturing the next generation HPV vaccines. Furthermore, boys should also be included in HPV vaccination programs to improve herd immunity, as well as prevent RRP and HPV-related head and neck cancers.