Effectiveness of mRNA-1273, BNT162b2, and BBIBP-CorV vaccines against infection and mortality in children in Argentina, during predominance of delta and omicron covid-19 variants: test negative, case-control study

Abstract

Objective To estimate the effectiveness of a two dose vaccine schedule (mRNA-1273, BNT162b2, and BBIBP-CorV) against SARS-CoV-2 infection and covid-19 related death and short term waning of immunity in children (3-11 years old) and adolescents (12-17 years old) during periods of delta and omicron variant predominance in Argentina. Design Test negative, case-control study. Setting Database of the National Surveillance System and the Nominalized Federal Vaccination Registry of Argentina. Participants 844 460 c hildren and adolescents without previous SARS-CoV-2 infection eligible to receive primary vaccination schedule who were tested for SARS-CoV-2 by polymerase chain reaction or rapid antigen test from September 2021 to April 2022. After matching with their corresponding controls, 139 321 (60.3%) of 231 181 cases remained for analysis. Exposures Two dose mRNA-1273, BNT162b2, and BBIBP-CorV vaccination schedule. Main outcome measures SARS-CoV-2 infection and covid-19 related death. Conditional logistic regression was used to estimate the odds of SARS-CoV-2 infection among two dose vaccinated and unvaccinated participants. Vaccine effectiveness was estimated as (1–odds ratio)×100%. Results Estimated vaccine effectiveness against SARS-CoV-2 infection was 61.2% (95% confidence interval 56.4% to 65.5%) in children and 66.8% (63.9% to 69.5%) in adolescents during the delta dominant period and 15.9% (13.2% to 18.6%) and 26.0% (23.2% to 28.8%), respectively, when omicron was dominant. Vaccine effectiveness declined over time, especially during the omicron period, from 37.6% (34.2% to 40.8%) at 15-30 days after vaccination to 2.0% (1.8% to 5.6%) after ≥60 days in children and from 55.8% (52.4% to 59.0%) to 12.4% (8.6% to 16.1%) in adolescents. Vaccine effectiveness against death related to SARS-CoV-2 infection during omicron predominance was 66.9% (6.4% to 89.8%) in children and 97.6% (81.0% to 99.7%) in adolescents. Conclusions Vaccine effectiveness in preventing mortality remained high in children and adolescents regardless of the circulating variant. Vaccine effectiveness in preventing SARS-CoV-2 infection in the short term after vaccination was lower during omicron predominance and decreasing sharply over time. Trial registration National Registry of Health Research IS003720.

A Review of the Data Supporting Use of COVID-19 Vaccinations in the Pediatric Population

“… 10 Data showing similar results have also been reported from multiple countries such as Argentina, Denmark, France, and Qatar, with some studies estimating 10-fold reductions in MIS-C with vaccination. 42 , 44 , 45 , 50 , 51 Although infection-based outcomes showed decreased effectiveness during Omicron, a decreased rate of MIS-C with vaccination has been described during Alpha, Delta, and Omicron predominance. 10 , 50 Most studies did not report many, if any fatalities; however, data from Argentina suggest a mortality benefit from vaccinations (66.9%-97% protection depending on age).…”

“… 10 , 50 Most studies did not report many, if any fatalities; however, data from Argentina suggest a mortality benefit from vaccinations (66.9%-97% protection depending on age). 51 …”

Association of Prior COVID-19 Vaccination With SARS-CoV-2 Infection and Death in Children and Young Persons During the Omicron Variant Period in Brazil

“…4 The protection against COVID-19-related death in our study was similar to data reported for children aged 5 to 11 years in other populational studies. 5,6 A limitation of our study is a possible underestimated VE against Omicron infection due to omitted vaccination time for most participants. Regardless of vaccine schedule, we observed low effectiveness in preventing Omicron infection in young people.…”

A peer says the government is “in deep shit,” and it couldn’t be more real

“…Study after study in The BMJ and other major journals has indicated the effectiveness of this vaccine technology (doi:10.1136/bmj.o2865 doi:10.1136/bmj-2022-073070 doi:10.1136/bmj-2022-072065). 567 Now, a new study in The BMJ shows that maternal mRNA covid-19 vaccination during pregnancy protects infants against SARS-CoV-2 infection and hospital admission (doi:10.1136/bmj-2022-074035). 8…”