Monitoring Hpv Vaccination Program Impact In Bhutan And Rwanda
Gary CLIFFORD, International Agency for Research on Cancer, France
UMULISA C. 2
, TSHOMO U. 3
, TENET V. 1
, LAZZARATO F. 1
, TOMMASINO M. 1
, GHEIT T. 1
, BAUSSANO I. 1
, FRANCESCHI S. 1
1 Section of Infections, International Agency for Research on Cancer, Lyon, France
2 Rwanda Ministry of Health, Rwanda
3 Jigme Dorji Wangchuck National Referral Hospital (JDW/NR) Hospital, Thimphu, Bhutan
Human papillomavirus (HPV) vaccination is expected to reduce the high number of cervical cancer deaths in low- and middle-income countries (LMIC), but not within 20 years. Hence, reliable early evidence of effectiveness is crucial to encourage national planners to implement and sustain programs. Bhutan (2010) and Rwanda (2011) were the first countries in Asia and Africa to introduce national, primarily school-based, vaccination (HPV6/11/16/18) programs. These target 12 year-old girls and included catch-up campaigns up to 18 years. Approval of long-term protocols to monitor HPV prevalence in both settings, offers an opportunity to demonstrate HPV vaccine effectiveness in LMIC.
Methods and Results
Firstly, baseline HPV prevalence was characterized among unvaccinated population-based female cohorts, by collecting cervicovaginal samples from ~2,500 women aged 18-69 years in both Bhutan [Tshomo, BMC Infect Dis, 2014] and Rwanda [Ngabo, submitted], of whom 18% and 22%, respectively, were infected with high-risk HPV. Women under 25 years (22% and 32% HR HPV prevalence, respectively), were oversampled to establish a robust sample with which to compare future vaccinated cohorts.
Secondly, to obtain earliest indicators of vaccine impact, we piloted school-based surveys of HPV testing from urine. 973 and 912 female students in Bhutan and Rwanda, respectively (mean age=19 years), self-collected first-void urine samples [Franceschi, Int J Cancer, 2016]. 92% and 43% reported vaccination, respectively, and HPV6/11/16/18 prevalence was lower in vaccinated than in unvaccinated (vaccine effectiveness = 68% and 88% respectively).
We also monitor HPV types in CIN2/3 and cervical cancer, and are evaluating HPV testing as a primary screening test, both to anticipate reductions in cervical cancer mortality in older women, and to facilitate long-term monitoring of HPV prevalence.
Recent findings mark the beginning of demonstrating HPV vaccine impact in Bhutan and Rwanda, and support the feasibility of urine HPV surveys for this purpose.