title: Severity and age of rotavirus diarrhea, but not socioeconomic conditions, are associated with rotavirus seasonality in Venezuela.
abstract: Rotavirus (RV) epidemiology presents differences between developing and developed countries among which are seasonality, age at first infection, variability of strain in circulation and severity of disease. Since, in Venezuela, we have distinct seasonal patterns of RV occurrence, we examined the epidemiological profile of RV disease associated to these differences by analyzing data from previous studies conducted in Venezuela. Data were collected from children <5 years of age with diarrhea seen in six hospitals located in five cities. Socio-demographic and clinical characteristics of RV illness were analyzed according to RV identification by ELISA assay and the seasonal patterns of RV circulation (marked versus minimal seasonality). A total of 6,742 episodes of diarrhea (1,820 rotavirus positive and 4,922 rotavirus negative) were evaluated: 1,951 in Caracas, Cumaná and Pto. Ordaz (minimal seasonality) and 4,791 in Mérida and Valencia (marked seasonality). Mean age (months) of children with RV was 8.14 +/- 6.74 and 12.21 +/- 9.62 (P < 0.0001) in areas with minimal and marked seasonality, respectively. RV disease was more frequent (33% vs. 24%; OR = 1.536; 95% CI: 1.36-1.73), more severe (dehydration: 64% vs. 29%; OR = 4.436; 95% CI: 3.61-5.44) and more common in infants than in older children (79% vs. 60%; OR = 2.521; 95% CI: 2.01-3.14) in cities with minimal seasonality than in those with marked seasonality. Socioeconomic conditions were not associated with seasonality. In environments with minimal seasonality, children are infected with RV at younger ages and the disease is more severe regardless of malnutrition and poverty.
authors.affiliation: Instituto de Biomedicina, Ministerio de Salud, Universidad Central de Venezuela, Fuvesin, Caracas, Venezuela.
authors.forename: Irene Pérez
authors.initials: IP
authors.lastname: Schael
authors.forename: Rosabel
authors.initials: R
authors.lastname: González
authors.forename: Belén
authors.initials: B
authors.lastname: Salinas
mesh_terms: D000367:Age Factors; D000818:Animals; D002675:Child, Preschool; D002947:Cities; D003967:Diarrhea / Q000453:epidemiology* / Q000821:virology*; D005260:Female; D006761:Hospitals; D006801:Humans; D007223:Infant; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D012401:Rotavirus / Q000302:isolation & purification*; D012400:Rotavirus Infections / Q000453:epidemiology*; D012621:Seasons; D012720:Severity of Illness Index; D012959:Socioeconomic Factors; D014505:Urban Population; D014687:Venezuela / Q000453:epidemiology