Rotavirus genotype distribution during the pre-vaccine period in Bolivia: 2007–2008

Abstract

Summary Objectives Rotavirus is 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[8] (33%), G1P[6] (17%), G2P[4] (13%), G9P[6] (12%), and G1P[8] (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[6] 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.

Burden of Norovirus and Rotavirus in Children After Rotavirus Vaccine Introduction, Cochabamba, Bolivia

“…The literature describing the burden of rotavirus in Bolivia has demonstrated the effectiveness of rotavirus vaccine in the region. 5,6,14,16,17 Seven years before vaccine introduction at this study site, rotavirus was detected by PCR in 24% of 317 children aged < 5 years hospitalized with AGE. 17 Rotavirus prevalence was 36% when children < 2 years were analyzed separately, nearly double the prevalence described here (19%).…”

“…5,[35][36][37] Despite effective vaccination, rotavirus remains a major cause of pediatric diarrheal disease, and prevalence has remained high in Latin American countries that have not included rotavirus vaccine into national vaccine schedules. 38,39 Most children in the study received a full two-dose course of Rotarix before enrollment (78.3%).…”

“…2 Norovirus and rotavirus are the major causes of diarrheal illness in South American children. [3][4][5][6][7][8][9] Recent data suggest that the relative burden of norovirus versus rotavirus in children with AGE may be changing after widespread adoption of rotavirus vaccine. Relatively little is known of viral etiology of pediatric AGE in low income, high mortality settings after vaccine introduction.…”

Genotypic Distribution of Rotavirus in Phnom Penh, Cambodia: An Association of G9 with More Severe Diseases

“…23 However, G9 association with increased severity is debatable as others reported that G1 had greater association with severe dehydration when compared with G9, 24,25 whereas other studies showed no difference of severity with any specific G-genotypes. [26][27][28] Differences in clinical severity associated G-genotypes may rely on the geographical origin of the strain or associated P-genotypes. 23 In addition, a significant difference of genotype distribution of rotavirus between outpatient and hospitalized cases may suggest that surveillance of rotavirus in only hospitalized severe diarrhea cases may not accurately represent distribution of rotavirus strains circulating in the area.…”

Risk Factors for Diarrhea in Children Under Five Years of Age Residing in Peri-urban Communities in Cochabamba, Bolivia

“…54,55 The Bolivian Ministry of Health introduced rotavirus vaccine in 2008. 56 Unfortunately, in this study systematic data on rotavirus vaccination was not collected.…”