Impact of catch-up human papillomavirus vaccination on cervical cancer incidence in Kenya: A mathematical modeling evaluation of HPV vaccination strategies in the context of moderate HIV prevalence

Gui Liu; Nelly R Mugo; Cara Bayer; Darcy White Rao; Maricianah Onono; Nyaradzo M Mgodi; Zvavahera M Chirenje; Betty W Njoroge; Nicholas Tan; Elizabeth A Bukusi; Ruanne V Barnabas

doi:10.1016/j.eclinm.2022.101306

Impact of catch-up human papillomavirus vaccination on cervical cancer incidence in Kenya: A mathematical modeling evaluation of HPV vaccination strategies in the context of moderate HIV prevalence

EClinicalMedicine. 2022 Feb 19:45:101306. doi: 10.1016/j.eclinm.2022.101306. eCollection 2022 Mar.

Authors

Gui Liu¹, Nelly R Mugo^{1

2}, Cara Bayer¹, Darcy White Rao³, Maricianah Onono², Nyaradzo M Mgodi⁴, Zvavahera M Chirenje⁵, Betty W Njoroge², Nicholas Tan⁶, Elizabeth A Bukusi^{1

2

7}, Ruanne V Barnabas^{1

3

7

8}

Affiliations

¹ Department of Global Health, University of Washington, Seattle, USA.
² Kenya Medical Research Institute, Nairobi, Kenya.
³ Department of Epidemiology, University of Washington, Seattle, USA.
⁴ University of Zimbabwe Clinical Trials Research Centre, Harare, Zimbabwe.
⁵ Faculty of Medicine and Health Sciences, University of Zimbabwe, Harare, Zimbabwe.
⁶ Creighton University School of Medicine, Phoenix, USA.
⁷ Department of Obstetrics and Gynecology, University of Washington, Seattle, USA.
⁸ Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, USA.

Abstract

Background: Cervical cancer incidence is high in Kenya due to HIV and limited access to cancer prevention services. Human papillomavirus (HPV) has been shown to increase HIV acquisition; however, the potential impact of HPV vaccination on HIV is unknown. We modeled the health impact of HPV vaccination in the context of the HIV epidemiology in Kenya.

Methods: Using a validated compartmental transmission model of HIV and HPV set in Kenya, we evaluated five scenarios of nonavalent HPV vaccination: single-age-vaccination of 10-year-old girls at 90% coverage; multi-age-cohort (MAC) vaccination of 10-14-year-old girls at 90% coverage; MAC plus moderate-coverage (50%) catch-up vaccination of 15-24-year-old women; MAC plus high-coverage (80%) catch-up of 15-24-year-old women; and MAC plus catch-up of 15-44-year-old women at 80% coverage (HPV-FASTER). We compared cervical cancer incidence, HIV prevalence, and cumulative cervical cancer and HIV cases averted after 50 years to a baseline scenario without vaccination. In all scenarios, we assumed the UNAIDS 90-90-90 goal for HIV treatment is attained by 2030.

Findings: In 2021, model-estimated cervical cancer incidence is 44/100,000 and HIV prevalence among women is 6·5%. In 2070, projected cancer incidence declines to 27/100,000 and HIV prevalence reaches 0·3% without vaccination. With single-age-vaccination, cancer incidence in 2070 is reduced by 68%, averting 64,529 cumulative cancer cases. MAC vaccination reduces cancer incidence by 75%, averting 206,115 cancer cases. Moderate and high-coverage catch-up and HPV-FASTER reduce cancer incidence by 80%, 82%, and 84%, averting 254,930, 278,690, and 326,968 cancer cases, respectively. In all scenarios, HIV prevalence in 2070 is reduced by a relative 8-11%, with 15,609-34,981 HIV cases averted after 50 years.

Interpretation: HPV vaccination can substantially reduce cervical cancer incidence in Kenya in the next 50 years, particularly if women up to age 24 are vaccinated. HIV treatment scale-up can also alleviate cervical cancer burden. However, HPV vaccination has modest additional impact on HIV when antiretroviral therapy coverage is high.

Funding: National Institutes of Health, Bill and Melinda Gates Foundation.

Keywords: Cervical cancer; HIV; HPV; HPV vaccination; Mathematical model.

Abstract

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