Viral Etiologies of Childhood Diarrhea in Developing Countries: A Case Study in Ghana

Abstract

Diarrheal diseases cause significant morbidity and mortality worldwide, particularly in children under age 5. Most of the estimated 2.5 million annual diarrhea-related deaths occur in developing countries, where access to treatment is limited. Rotaviruses, the leading cause of childhood diarrhea, cause about 527,000 deaths each year around the world, while noroviruses, the second leading viral etiology of diarrhea, cause about 218,000 child deaths a year. Oral rotavirus vaccines have proven highly effective against rotavirus disease in industrialized settings. However, vaccine efficacy is reduced in developing nations. To explore this efficacy gap, this thesis examines the epidemiology of rotaviruses in Ghana, a developing country in West Africa. Furthermore, while norovirus vaccines are currently still in development, the burden of norovirus disease in most developing nations has yet to be established. Through the molecular analyses of 152 stool specimens collected from sites throughout the country, this study demonstrates that noroviruses, primarily of genogroup II, are a significant contributor to the childhood diarrheal disease burden in Ghana. The results establish the baseline norovirus prevalence in this developing country prior to the recent introduction of a monovalent rotavirus vaccine. Overall, the thesis highlights the potential for future interventions against the viral etiologies of childhood diarrhea.