Objectives: Rotavirusis the most important etiology of severe diarrhea in Bolivia. The monovalent attenuated human oral rotavirus vaccine Rotarix® was introduced in Bolivia in 2008. We describe the molecular epidemiology of circulating rotavirus strains before vaccine introduction. Methods: Two thousand one hundred thirty-five diarrheal samples were collected from hospitals in four Bolivian cities during 2007-2008. Forty-three percent (445 of 1030 rotavirus-positive samples) were analyzed for G and P genotypes. Among those, 331 were electropherotyped by polyacrylamide gel electrophoresis. Disease severity was quantified using a modified Vesikari scale. Results: Among the 445 samples, five genotypes were found to be prevalent: G9P (33%), G1P (17%), G2P (13%), G9P (12%), and G1P (4%). Co-infections with two or more strains accounted for 14% of samples. The most prevalent strain, G9, showed greater electropherotype diversity compared to other serogroups. Strain G1P generally infected younger children and peaked later in the year than other strains. No particular genotype was associated with a higher severity score, though there was a significant difference in the duration of diarrhea between genotypes. Conclusions: During the 2-year pre-vaccine period, substantial diversity of rotavirus co-circulating strains was observed. These data constitute a baseline against which changes in circulating strains post-vaccine introduction can be monitored.
Nota bibliográficaFunding Information:
This work is part of the UMSA-IBMB “Diarrheal Disease Program” supported by the Swedish International Development Cooperation Agency (SIDA). Support was also obtained from the Pan American Health Organization (PAHO), Ministerio de Salud y Deportes: Programa Ampliado de Inmunización (PAI), and partly by The Eugene J. Gangarosa Fund, the Anne E. and William A. Foege Global Health Fund, the O.C. Hubert Charitable Trust, the RSPH Student Initiative Fund, the NIH Global Frameworks Grant (2007–2010), and the Emory University Global Health Institute. JSL was supported in part by funds from the Emory University Global Health Institute, NIH-NIAID (1K01AI087724 - 01) and USDA-NIFA (2010-85212-20608) grants. PAR was supported by Award Number T32AI074492 from the National Institute of Allergy and Infectious Diseases. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Allergy and Infectious Diseases or the National Institutes of Health. We are grateful for the support of SEDES La Paz, El Alto, Cochabamba and Santa Cruz, the hospitals and the hospital staff participating in this study.