Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brasil 4365 Pavilhão Hélio e Peggy Pereira, Manguinhos, Rio de Janeiro, Rio de Janeiro, Brazil.
Laboratory of Epidemiology and Molecular Systematics, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Av. Brasil 4365 Pavilhão Leonidas Deane, Manguinhos, Rio de Janeiro, Rio de Janeiro, Brazil.
BMC Pediatr. 2019 Jan 31;19(1):42. doi: 10.1186/s12887-019-1415-9.
Brazil introduced the monovalent rotavirus vaccine (Rotarix®) in 2006. This study aimed to assess the epidemiology and genotype distribution of species-A rotavirus (RVA) in Brazil, comparing the pre- and post-vaccination periods.
Laboratory-based RVA surveillance included 866 municipalities in 22 Brazilian states, over a 21-year period. A total of 16,185 children with diarrheal diseases (DD) aged up to 12 years between 1996 and 2005 (pre-vaccination period, n = 7030) and from 2006 to 2017 (post-vaccination period, n = 9155) were enrolled. RVA was detected using ELISA immune assay and/or polyacrylamide gel electrophoresis and genotyped using nested PCR and/or nucleotide sequencing. RVA-positivity and genotypes detection rates were compared in distinct periods and age groups and Rotarix vaccination status.
RVA-positivity in pre- and post-vaccination periods was, respectively: 4-11 months bracket, 33.3% (668/2006) and 16.3% (415/2547) (p < 0.001); 12-24 months, 28.2% (607/2154) and 22.2% (680/3068) (p < 0.001); 25-48 months, 17.4% (215/1235) and 29.4% (505/1720) (p < 0.001). Genotypes distribution in the pre- and post-vaccination periods was, respectively: G1P [8]/G1P[Not Typed], 417/855 (48.8%) and 118/1835 (6.4%) (p < 0.001); G2P [4]/G2P[NT], 47/855 (5.5%) and 838/1835 (45.7%) (p < 0.001); G3P [8]/G3P[NT], 55/855 (6.4%) and 253/1835 (13.8%) (p < 0.001); G9P [8]/G9P[NT], 238/855 (27.8%) and 152/1835 (8.3%) (p < 0.001); G12P [8]/G129P[NT], 0/871 (0%) and 249/1835(13.6%) (p < 0.001). Concerning infants aged 4-11 months, RVA frequency in fully vaccinated and non-vaccinated individuals was 11.9% (125/1052) and 24.5% (58/237) (p < 0.001), respectively. In children aged 12-24 months, RVA detection rate was 18.1% (253/1395) and 29.6% (77/260) (p < 0.001), for the vaccinated and non-vaccinated individuals, respectively (p < 0.001).
RVA infection was significantly less frequent in children aged ≤2 years with DD after implementing vaccination, mainly among vaccinated children. It was also observed a decrease of P [8] circulation and emergence of G2P[4] in 2005, and afterwards in the post-vaccine era, with spreading of G12P[8] in 2014-2015 and of G3P[8] in 2017. Continuous RVA surveillance must be carried out in this scenario.
巴西于 2006 年引入单价轮状病毒疫苗（Rotarix®）。本研究旨在评估巴西 A 型轮状病毒（RVA）的流行病学和基因型分布，并比较疫苗接种前后的情况。
实验室轮状病毒监测包括巴西 22 个州的 866 个城市，时间跨度为 21 年。1996 年至 2005 年（疫苗接种前时期，n=7030）和 2006 年至 2017 年（疫苗接种后时期，n=9155）期间，共有 16185 名年龄在 12 岁以下患有腹泻病（DD）的儿童入组。采用酶联免疫吸附试验（ELISA）和/或聚丙烯酰胺凝胶电泳检测 RVA，采用巢式 PCR 和/或核苷酸测序进行基因分型。比较了不同时期和年龄组的 RVA 阳性率和基因型检出率，以及 Rotarix 疫苗接种状况。
疫苗接种前和后时期的 RVA 阳性率分别为：4-11 个月组，33.3%（668/2006）和 16.3%（415/2547）（p<0.001）；12-24 个月组，28.2%（607/2154）和 22.2%（680/3068）（p<0.001）；25-48 个月组，17.4%（215/1235）和 29.4%（505/1720）（p<0.001）。疫苗接种前和后时期的基因型分布分别为：G1P[8]/G1P[未定型]，417/855（48.8%）和 118/1835（6.4%）（p<0.001）；G2P[4]/G2P[未定型]，47/855（5.5%）和 838/1835（45.7%）（p<0.001）；G3P[8]/G3P[未定型]，55/855（6.4%）和 253/1835（13.8%）（p<0.001）；G9P[8]/G9P[未定型]，238/855（27.8%）和 152/1835（8.3%）（p<0.001）；G12P[8]/G129P[未定型]，0/871（0%）和 249/1835（13.6%）（p<0.001）。对于 4-11 个月大的婴儿，完全接种和未接种疫苗的个体中 RVA 的频率分别为 11.9%（125/1052）和 24.5%（58/237）（p<0.001）。对于 12-24 个月大的儿童，RVA 检出率分别为 18.1%（253/1395）和 29.6%（77/260）（p<0.001），这是完全接种和未接种疫苗的个体。
接种疫苗后，≤2 岁患有 DD 的儿童中 RVA 感染的频率显著降低，主要是在接种疫苗的儿童中。此外，还观察到 2005 年 P[8]的流行减少，G2P[4]的出现，随后在疫苗接种后时期，G12P[8]于 2014-2015 年传播，G3P[8]于 2017 年传播。在此情况下，必须继续进行轮状病毒的持续监测。
