Division of Pediatric Infectious Diseases, Department of Pediatrics, Santa Casa School of Medical Sciences, São Paulo, Brazil.
Pediatr Infect Dis J. 2010 Nov;29(11):1019-22. doi: 10.1097/INF.0b013e3181e7886a.
Brazil implemented routine immunization with the human rotavirus vaccine, Rotarix, in 2006 and vaccination coverage reached 81% in 2008 in São Paulo. Our aim was to assess the impact of immunization on the incidence of severe rotavirus acute gastroenteritis (AGE).
We performed a 5-year (2004-2008) prospective surveillance at a sentinel hospital in São Paulo, with routine testing for rotavirus in all children less than 5 years of age hospitalized with AGE. Genotypes of positive samples were determined by reverse transcription polymerase chain reaction.
During the study, 655 children hospitalized with AGE were enrolled; of whom 169 (25.8%) were positive for rotavirus. In the postvaccine period, a 59% reduction in the number of hospitalizations of rotavirus AGE and a 42.2% (95% confidence interval [CI], 18.6%-59.0%; P = 0.001) reduction in the proportion of rotavirus-positive results among children younger than 5 years were observed, with the greatest decline among infants (69.2%; 95% CI, 24.7%-87.4%; P = 0.004). Furthermore, the number of all-cause hospitalizations for AGE was reduced by 29% among children aged <5 years. The onset and peak incidences of rotavirus AGE occurred 3 months later in the 2007 and 2008 seasons compared with previous years. Genotype G2 accounted for 15%, 70%, and 100% of all cases identified, respectively, in 2006, 2007, and 2008.
After vaccine implementation, a marked decline in rotavirus AGE hospitalizations was demonstrated among children younger than 5 years of age, with the greatest reduction in the age groups targeted for vaccination. The predominance of genotype G2P[4] highlights the need of continued postlicensure surveillance studies.
巴西于 2006 年开始对人轮状病毒疫苗（Rotarix）进行常规免疫接种，2008 年圣保罗的疫苗接种覆盖率达到 81%。我们的目的是评估免疫接种对严重轮状病毒急性胃肠炎（AGE）发病率的影响。
我们在圣保罗的一家哨点医院进行了为期 5 年（2004-2008 年）的前瞻性监测，对所有因 AGE 住院的 5 岁以下儿童进行常规轮状病毒检测。通过逆转录聚合酶链反应确定阳性样本的基因型。
在研究期间，共纳入 655 例因 AGE 住院的儿童；其中 169 例（25.8%）轮状病毒检测阳性。在疫苗接种后时期，轮状病毒 AGE 住院人数减少了 59%，5 岁以下儿童中轮状病毒阳性结果的比例减少了 42.2%（95%置信区间[CI]，18.6%-59.0%；P=0.001），婴儿的下降幅度最大（69.2%；95% CI，24.7%-87.4%；P=0.004）。此外，5 岁以下儿童因 AGE 导致的所有原因住院人数减少了 29%。与前几年相比，2007 年和 2008 年的轮状病毒 AGE 发病和高峰期分别推迟了 3 个月。2006 年、2007 年和 2008 年，所有病例中基因型 G2 分别占 15%、70%和 100%。
疫苗接种实施后，5 岁以下儿童的轮状病毒 AGE 住院人数明显下降，接种目标年龄组的降幅最大。基因型 G2P[4]的优势突显了继续进行疫苗上市后监测研究的必要性。
