First assessment of all-cause acute diarrhoea and rotavirus-confirmed cases following massive vaccination in Argentina

Abstract

Argentina incorporated rotavirus massive vaccination in 2015. No specific strategy has been designed to accurately measure the impact of this recent introduction on the diarrhoeal disease burden in our country. We assessed post-vaccine introduction data (all-cause acute diarrhoea and rotavirus laboratory-confirmed cases, and genotype distribution), compared with pre-vaccination period in children under 5 years of age in Argentina. Cross-sectional ecologic analysis was conducted with data from the Argentine Surveillance Health System. Endemic channel and global and seasonal incidence rates of pre- and post-vaccination periods were calculated and further compared. Conventional binary genotypification on rotavirus-positive samples was also performed. In post-vaccination period, a global decrease of 20.8% in the rate of all-cause acute diarrhoea cases was found. The endemic channel showed that declination was more significant in the autumn/winter season. Rotavirus laboratory-confirmed cases showed 61.7% of reduction and the weekly distribution analyses indicated a significant flattening of the expected seasonal peak. G2P[4] was the most prevalent circulating genotype (57.2%). This study represents the first assessment of diarrhoeal disease burden since rotavirus massive vaccination strategy was implemented in Argentina. This introduction represented a successful intervention due to the significant decrease in all-cause acute diarrhoea cases and rotavirus laboratory-confirmed cases.

Rotavirus A in Brazil: Molecular Epidemiology and Surveillance during 2018–2019

“…However, it is worth mentioning that both studies involved children hospitalized for severe AGE. In Argentina, RVA positivity decreased from 26.8% to 13.6% comparing the pre- and post-vaccination periods [ 37 ]. Other studies performed elsewhere have described RVA detection rates varying from 8.4% to 23.2% [ 38 , 39 , 40 , 41 , 42 ].…”

Emergence of Unusual Rotavirus G9p[4] and G8p[8] Strains During Post Vaccination Surveillance in Argentina, 2017-2018 

“…However, rapid and successful results were observed regarding burden of diarrheal disease [14]. Following four years of this strategy, the prevalence of rotavirus remained low in children under 5 years of age in comparison with the previous study [14]. These ndings oppose to other experiences that had described an increase in the laboratory con rmed cases every two years [21].…”

“…Argentina was one of the latest countries to adopt universal rotavirus vaccination in the Americas. However, rapid and successful results were observed regarding burden of diarrheal disease [14]. Following four years of this strategy, the prevalence of rotavirus remained low in children under 5 years of age in comparison with the previous study [14].…”

“…In general, it has been highly prevalent in different countries in Africa but recently has also been detected in South Asia and Europe [33][34][35][36]. In Latin America, it has been sporadically detected in humans in association with P [4] and P [6] in Brazil, P [6] in Argentina, P [14] in Venezuela, and P [1] in Paraguay, these latter two related with interspecies transmission [37][38][39]. As G8P [8], it was identi ed in several countries of Central America and recently in Chile during a community diarrheal surveillance [40,41].…”

“…Also, genotype distribution has been extensively described with co-circulation and interannual uctuation mostly among common strains [10][11][12][13]. In 2015, Rotarix ™ monovalent vaccine (human G1P [8]) was included for universal administration and its rst impact study showed a sharp decrease on all-cause and rotaviruscon rmed cases and an immediate predominance of the G2P [4] genotype [14]. To assess the continuity of this intervention over time, the aim of this study is to analyze the impact of rotavirus vaccination on the burden of disease and genotype distribution in our country during the 2017-2018 period.…”