Schistosoma mansoni (Sm) and hepatitis B virus (HBV) are both endemic infections in sub-Saharan Africa with
substantial prevalence, morbidity and mortality. In Uganda, prevalence estimates for Sm and HBV are 25% and
10%, respectively. Sm infection biases immunological responses towards Th2 and regulatory patterns which
could potentially result in significant immune interactions at various stages of HBV infection. However, limited
data address the clinical or immunological impact of Sm and HBV coinfection. Proposed is a clinical and
mechanistic investigation to characterize the nature and magnitude of impact from Sm infection on the course of
chronic HBV. Led by Ugandan investigators proficient in leading high-level research on viral hepatitis and
Schistosomiases epidemiology and immunology, this study builds on long-standing collaborative work between
Ugandan, US, and UK investigators and leverages substantive in-country research infrastructure and expertise.
In Aim 1, we characterize the course of Sm infection in chronic HBV patients utilizing both novel and standard
assays for diagnosing Sm, while concurrently establishing a cohort of individuals for longer-term investigation.
In Aim 2, we systematically evaluate HBV serology, virology and clinical measures of disease (e.g., Fibroscan,
ultrasound) at study entry compared to six months post praziquantel treatment, and then over up to three years
of follow-up. In Aim 3, we explore focused immunological studies comparing liver biopsy to peripheral blood
samples to evaluate potential mechanisms by which Sm and HBV interaction may occur. These studies support
technology transfer of a novel, highly sensitive Sm assay as well as directly support the career development of
several early-stage Ugandan investigators. Findings from the proposed studies will provide novel insight for
improving the clinical management and mechanistic understanding of Sm and HBV coinfection, with implications
for many regions of Africa with co-occurring endemics of these two infections.