IVI and Tanzania

 

Ongoing Collaboration

 

Global Burden of Human Papillomavirus (GLOBE HPV)

IVI and its partners are conducting GLOBE HPV, a global disease burden study to generate robust primary data on the prevalence and impact of human papillomavirus (HPV) among girls and women in low- and middle-income countries across South Asia and sub-Saharan Africa. This five-year study aims to estimate the prevalence of high-risk HPV genotype infections among representative samples of girls and women aged 9 to 50 years, as well as specific subpopulations, to better understand the incidence of persistent HPV infection.

 

The study spans three countries in Asia: Bangladesh, Nepal, and Pakistan; and five in sub-Saharan Africa: the Democratic Republic of the Congo, Ghana, Sierra Leone, Tanzania, and Zambia. In Tanzania, IVI works alongside the Mwanza Intervention Trials Unit (MITU) and the National Institute for Medical Research (NIMR).

 

The study consists of cross-sectional surveys in general populations, longitudinal studies, special population studies, and qualitative research. In addition to assessing HPV prevalence, researchers will collect data on girls’ and women’s knowledge, attitudes, and beliefs regarding HPV interventions, perceptions of gender norms and stigma, and gender-related factors that may influence HPV burden or create barriers to accessing and utilizing HPV prevention, screening, and treatment services. 

 

In 2024, large-scale cross-sectoral surveys and longitudinal cohort studies were launched across all eight countries. The findings from this study will provide a more accurate understanding of the HPV disease burden and the obstacles to effective interventions at both national and global levels. These insights will help inform policymakers and health program designers, guiding research and development efforts toward interventions with the greatest potential public health impact. 

 

GLOBE HPV is done in collaboration with the London School of Hygiene and Tropical Medicine, the Karolinska Institutet, and the U.S. CDC and is made possible by $17.2 million USD in funding from the Gates Foundation and the Government of Sweden.

 

Previous Collaboration

 

Typhoid Surveillance in sub-Saharan Africa Program (TSAP)

From 2010 to 2014, IVI’s The Typhoid Fever Surveillance in Africa Program (TSAP) obtained comparable incidence data on typhoid fever and invasive nontyphoidal Salmonella (iNTS) disease in sub-Saharan Africa through standardized surveillance in ten countries (Burkina Faso, Ethiopia, Ghana, Guinea-Bissau, Kenya, Madagascar, Senegal, South Africa, Sudan, and Tanzania).

 

In Tanzania, TSAP ran from 2011 to 2013, conducting surveillance in the cities of Moshi, Muheza, and Tanga in collaboration with Kilimanjaro Christian Medical Centre and Duke University Medical Center of the United States. The studies in Moshi and Tanga were a follow-up to a 2007-2009 IVI study which examined the cost of illness from typhoid and other salmonella infections, and public knowledge and practices regarding these infections.

 

Each TSAP site conducted passive surveillance for bloodstream infections among febrile patients to isolate and identify aerobic bacteria from the patients’ blood. Healthcare utilization surveys were conducted to adjust population denominators in incidence calculations for differing healthcare utilization patterns and improve comparability of incidence rates across sites. The results of TSAP indicated that enteric fever caused by Salmonella Typhi and non-typhoidal Salmonella are significant problems in Africa and that the prevalence of multi-drug resistance may limit appropriate treatment options.

 

Along with its new disease burden discoveries, TSAP and its collaborators strengthened local surveillance capacities at multiple sites across sub-Saharan Africa, creating a system that has improved bacterial disease diagnostics, disease surveillance, reporting, and analysis systems in the region. 

 

Cholera Vaccine Effectiveness Trial

From 2009 to 2010, IVI conducted an oral cholera vaccine (OCV) effectiveness study in Tanzania in collaboration with the WHO, the Zanzibar Ministry of Health, and the Swiss Tropical and Public Health Institute with support from Sweden’s SIDA. 

 

In January and February 2009, approximately 30,000 people aged 2 and over received two doses of the Dukoral OCV at study sites on Zanzibar and Pemba islands. 

 

The result of the effectiveness trial showed the vaccine provided 70% protection during the first year of follow-up. IVI conducted an analysis of herd immunity conferred by the vaccine and found clear evidence of protection in those who were not vaccinated against cholera. This additional and indirect benefit of oral cholera vaccines helped further develop the case for the use of OCV, especially in outbreak situations.