Epidemiological features of rotavirus infection in Caracas, Venezuela: Implications for rotavirus immunization programs

Abstract

The epidemiological features of rotavirus infection may be quite relevant for evaluation of the performance of a rotavirus vaccine in different settings, as well as for monitoring its impact during vaccination under routine conditions. This article describes some important issues regarding rotavirus epidemiology in Venezuela, where major field trials of rotavirus vaccine have been carried out. Rotaviruses was significantly more frequently observed in inpatient (43%) than in outpatient (21%) consultations for diarrhea in infants and young children. There was a high prevalence of rotavirus illness, regardless of socioeconomic conditions, but the risk of dehydration was greater among the lower socioeconomic groups. Rotavirus disease occurs year-round, with a slight seasonal pattern. Eighty-five percent of rotavirus-positive diarrheal episodes, as well as 86% of cases of dehydration due to rotavirus, occurred during the first year of life. However, rotavirus illnesses occur less commonly during the first months of life (0-2 months), which may be a result of protection by transplacental antibodies. The pattern of acquisition of rotavirus antibody was consistent with this age distribution of disease and with optimal age for vaccination. Thus, regional epidemiological characteristics of rotavirus infection may affect optimal performance of rotavirus vaccine.

Rotavirus Prevalence in the Primary Care Setting in Nicaragua after Universal Infant Rotavirus Immunization

“…[15][16][17][18] We also confirmed broad coverage of the rotavirus vaccine among the children in the study. By distributing the vaccine through Nicaragua's EPI, 90.7% of the children were up to date on the vaccine.…”

Serological and molecular diversity of human rotavirus in São Paulo, Brazil

“…G5, G6 and G9 were only found in mixtures with other genotypes. Cocirculation of several genotypes was reported by authors in Brazil (7,8), and in other countries as Venezuela (34), Australia (3) and India (23).…”

Detection, Subgroup Specificity, and Genotype Diversity of Rotavirus Strains in Children with Acute Diarrhea in Paraguay

“…In central Brazil as well as in Rio de Janeiro, Brazil, G2 strains were predominant and G4 strains were found in 1.5 and 10.0% of samples, respectively (1,6). In Venezuela, serotype G1 was the most prevalent, followed by serotype G2; the G4 serotype was found in only 6% of samples (28). In Argentina, in 1996 to 1997, G2 was the most common type, and G4 was found in only 5.1% of samples; in 1997 to 1998, G1 was the most prevalent type, followed by G4, found in 31.3% of samples (3).…”

“…A few cases were also found during the summer months, as described previously for Argentina (3) and some regions of Brazil (27,29). This seasonal pattern may be responsible for the age-specific distribution found in Paraguay, since, in countries where a seasonal pattern does occur, children tend to become infected at later ages, due to lack of continuous exposure to rotavirus, as opposed to countries without marked seasonality, where infants tend to become infected at an earlier age (28).…”

“…The VP7 serotype is designated a G serotype (because VP7 is a glycoprotein), and 15 G serotypes are recognized. The VP4 serotype is designated a P serotype (because VP4 is protease sensitive); there are 11 P serotypes, with subtypes in 4 of them, and 21 P genotypes described (14,16,19,23,28,30,32). P genotypes are designated by a number in brackets (19).…”