Nucleotide differences were quantified using the MegaAlignTM software (DNASTAR®, Inc – USA). All molecular analysis and sequencing reactions were performed at the virology laboratory of HC/UFPR. Statistical analysis was performed using the chi-squared test or Fisher’s exact test, as appropriate. The tests were performed using GraphPad Prism version 5.0 for Windows (GraphPad Software – San Diego, California, USA). Only two-tailed tests were

used. A p-value of < 0.05 was considered statistically significant. During the study period, see more 179 (179/1,140 – 15.7%) samples were positive for RVA; of these, 80 (80/179 – 44.7%) had enough samples for further analysis, and were selected for the performance of multiplex hemi-nested RT-PCR for genotypes determination and nucleotide sequence, when necessary. 72 samples (72/80 – 90%) were RT-PCR positive for RVA; of these, 78% (56/72) were from hospitalized patients. Fig. 1 shows the distribution of RVA during the eight-year study and its relation to monthly average temperature (°C) and rainfall (mm). Sixty-six (66/72 – 91.6%) samples were genotyped. The genotypes found were G4 P [8] (28/72 – 38.9%), G1 P [8] (22/72 – 30.5%), G9 P [8] (10/72 – 13.9%), G2 P [4] (5/72 – 6.9%), and G3 P[8] (1/72 – 1.4%). Six samples could not be sequenced, probably because the primers used did not correspond

to genotype investigated; also, these samples presented a weak find more band in the agarose gel, undermining the quality of sequencing reactions performed. Differences in G and P genotype distribution were detected in distinct years, reflecting the yearly change in epidemiology of human rotavirus, with an alternation between genotypes every one or two years (fig. 2). No mixed RVA infections were detected. After the implementation of the vaccination program, only G2 P [4] and GNT P [8] genotypes were found. A total of 69 (69/80 – 86.2%) medical records were reviewed. 65% of the patients were male. The median age of patients

was nine months (IQR, Phosphoprotein phosphatase 6 – 16.5 months), and most cases occurred in patients aged < 12 months. Despite the broad frequency of patients with underlying diseases, a total of 51% (37/72) of the patients were admitted primarily due to severity of diarrhea. Regarding the vaccination status of patients admitted after 2006, only two patients reported previous RVA immunization: one received the complete scheme and the other only the first dose; both were non-immunosuppressed patients. For clinical and laboratory data analysis, the patients were divided into two groups according to age: children ≤ 12 months (65%, 45/69) and children > 12 months (35%, 24/69). Comparison of the clinical ward showed a greater frequency of patients < 12 months in the intensive care unit (ICU) (p = 0.008). A total of 64% of children presented dehydration, of which 78.3% were ≤ 12 months (p = 0.01) (Table 1). Three (3.7%) children evolved to death, one related to gastroenteritis.