Laboratorio de Gastroenteritis Virales, INEI-ANLIS "Dr. Carlos G. Malbrán", Av. Vélez Sársfield 563, Buenos Aires, Argentina.
Laboratorio de Gastroenteritis Virales, INEI-ANLIS "Dr. Carlos G. Malbrán", Av. Vélez Sársfield 563, Buenos Aires, Argentina.
Infect Genet Evol. 2021 Sep;93:104940. doi: 10.1016/j.meegid.2021.104940. Epub 2021 May 24.
In 2015, Argentina included Rotarix™ monovalent vaccine for universal administration and it showed a sharp decline in all-cause and rotavirus-confirmed cases as well as an immediate predominance of the G2P[4] genotype. The aim of this study was to analyze the impact of rotavirus vaccination on laboratory-confirmed cases and genotype distribution in Argentina following its introduction.
Prevalence and seasonality of laboratory-confirmed rotavirus cases data were assessed. Analyses of circulating genotypes were performed by conventional binary characterization (G and P typing). Phylogenetic study of VP7 gene was performed from emergent unusual strains.
During 2017-2018, 1183 rotavirus cases (13.2%) were detected, and prevalence was uniform among different age subgroups. Weekly distribution showed a raise of confirmed cases around late July and early August. In 2017 the most frequently detected genotypes were G2P[4] and G3P[8]. However, in 2018 G12P[8] genotype increased and it was detected at a high rate. Noteworthy, the detection of uncommon G9P[4] and G8P[8] strains (bearing DS-1-like genetic backbones) was observed at moderate rates.
Following four years of universal vaccination, the prevalence of rotavirus remained low in children under 5 years of age with a shift of the seasonal peak in early spring. The emergence of uncommon genotypes was due to introduction of new strains rather than to reassortment of local strains. Continuous monitoring of rotavirus burden of disease and genotype distribution provides useful evidence to evaluate existing immunization strategies and to contribute in the development of new vaccines as well.
2015 年，阿根廷将 Rotarix™单价疫苗纳入全民免疫计划，这使得轮状病毒所有病例和确诊病例数量迅速下降，同时 G2P[4]基因型立即占据主导地位。本研究旨在分析轮状病毒疫苗接种在阿根廷引入后的实验室确诊病例和基因型分布的影响。
评估了实验室确诊轮状病毒病例的流行率和季节性。通过常规二元特征（G 和 P 型）分析了循环基因型。对新兴的异常株进行了 VP7 基因的系统进化研究。
2017-2018 年期间，检测到 1183 例轮状病毒病例（13.2%），不同年龄亚组的流行率一致。每周分布显示 7 月底和 8 月初确诊病例增加。2017 年最常检测到的基因型是 G2P[4]和 G3P[8]。然而，2018 年 G12P[8]基因型增加，其检出率很高。值得注意的是，还以中等频率检测到罕见的 G9P[4]和 G8P[8]株（携带 DS-1 样遗传骨架）。
在实施全民免疫计划四年后，5 岁以下儿童的轮状病毒流行率仍然较低，且季节性高峰提前到早春。罕见基因型的出现是由于新毒株的引入，而不是本地毒株的重组。对轮状病毒疾病负担和基因型分布的持续监测为评估现有免疫策略提供了有用的证据，并有助于开发新疫苗。
