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.

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 children 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.

Retorno social de la inversión tras eliminar la transmisión vertical de chagas, VIH/sida, HB y sífilis: caso de un municipio de la Provincia de Buenos Aires / Social Return on the investment of the elimination of the vertical transmission of Chagas, HIV / AIDS, HB and Syphilis: Case of a Municipality of the Province of Buenos Aires

Resumen Introducción: se busca cuantificar los retornos de la inversión asociados a una intervención en el sistema público de salud de un municipio de la Provincia de Buenos Aires, Argentina, consistente en el fortalecimiento de la estrategia denominada Eliminación de la Transmisión Maternoinfantil de la Infección por VIH, Sífilis, enfermedad de Chagas Congénita e Infección Perinatal por Hepatitis B (ETMI-PLUS). Metodología: el estudio (cuantitativo) se basa en la metodología de Retorno Social de la Inversión (RSI). Se establecieron definiciones ad-hoc para la medición de los retornos sobre la base de los datos disponibles provenientes de diversas fuentes: información primaria de la Secretaría de Salud del MAB; tasas de transmisión congénita de cada enfermedad notificados al Sistema Nacional de Vigilancia de Salud; presupuestos detallados de los recursos asignados al proyecto por parte de la Fundación Mundo Sano y costos de tratamientos e insumos de nomencladores oficiales. Resultados: por cada peso invertido para reforzar la ETMI-PLUS en el MAB, se obtuvo un retorno de casi 4 pesos, gracias a las mejoras en la eliminación vertical de las cuatro enfermedades y al descenso de las complicaciones cardiacas en las mujeres embarazadas diagnosticadas con chagas y tratadas oportunamente. Conclusiones: estos resultados sugieren la existencia de una relación retorno-inversión favorable, analizada bajo una perspectiva conservadora, ya que, se incluyen exclusivamente los ahorros para el sistema de salud y se excluyen otras dimensiones de los retornos vinculadas con las mejoras en los resultados alcanzados.

Abstract Introduction: we seek to quantify the returns on investment associated with an intervention in the public health system of a Municipality of the Province of Buenos Aires, Argentina. This intervention consists of strengthening the strategy for the Elimination of Mother-to-Child Transmission of HIV Infection, Syphilis, Congenital Chagas Disease and Perinatal Hepatitis B Infection, a strategy called ETMI-PLUS. Methodology: the study (quantitative) is based on the Social Return on Investment (RSI) methodology. Ad-hoc definitions are established for the measurement of returns based on the information available from various sources: primary information from the Ministry of Health of the MAB; rates of congenital transmission of each disease reported to the National Health Surveillance System; detailed budgets of the resources assigned to the project by Fundación Mundo Sano and costs of treatments and supplies from official nomenclators. Results: for each argentinean peso invested in strengthening the ETMI-PLUS in the MAB, a return of almost 4 pesos would have been obtained thanks to the improvements in the vertical elimination of the 4 diseases and the reduction of cardiac complications in pregnant women.Conclusions: these results suggest the existence of a return / investment relationship favorable to the intervention, analyzed under a conservative analysis since savings for the health system are exclusively included and other dimensions of returns associated with improvements in results are excluded.

Innovation and immunization program management: traceability and quality in Latin America and the Caribbean, laying the groundwork for a regional action plan.

INTRODUCTION: The Latin American Society of Pediatric Infectious Diseases (SLIPE by its Spanish acronyms) is working to understand the current situation, gaps, and opportunities for traceability of the quality vaccination process in Latin America and the Caribbean. AREAS COVERED: On September 24th and 25th, a Latin American forum of experts in immunization programs was held through the Zoom platform; the topics discussed included: computerized systems for recording immunizations, vaccination programs traceability, challenges, and information systems for the integrated management of vaccination. EXPERT OPINION: Latin American countries have transitioned from having a nominal registration system to a nominal tracking system, with many of them not migrating their platforms to new technologies; therefore, the low-quality data, fragmented databases, and slow information traffic present a challenge that must be taken on.

Effectiveness of rAd26-rAd5, ChAdOx1 nCoV-19, and BBIBP-CorV vaccines for risk of infection with SARS-CoV-2 and death due to COVID-19 in people older than 60 years in Argentina: a test-negative, case-control, and retrospective longitudinal study.

BACKGROUND: In January, 2021, a vaccination campaign against COVID-19 was initiated with the rAd26-rAd5, ChAdOx1 nCoV-19, and BBIBP-CorV vaccines in Argentina. The objective of this study was to estimate vaccine effectiveness at reducing risk of SARS-CoV-2 infection and COVID-19 deaths in people older than 60 years. METHODS: In this test-negative, case-control, and retrospective longitudinal study done in Argentina, we evaluated the effectiveness of three vaccines (rAd26-rAd5, ChAdOx1 nCoV-19, and BBIBP-CorV) on SARS-CoV-2 infection and risk of death in people with RT-PCR confirmed COVID-19, using data from the National Surveillance System (SNVS 2.0). All individuals aged 60 years or older reported to SNVS 2.0 as being suspected to have COVID-19 who had disease status confirmed with RT-PCR were included in the study. Unvaccinated individuals could participate in any of the analyses. People with suspected COVID-19 who developed symptoms before the start of the implementation of the vaccination programme for their age group or district were excluded from the study. The odds ratio of SARS-CoV-2 infection was evaluated by logistic regression and the risk of death in individuals with RT-PCR confirmed COVID-19 was evaluated by proportional hazard regression models, adjusted for possible confounders: age at the time of the symptom onset date, sex, district of residence, epidemiological week corresponding to the symptom onset date, and history of COVID-19. The estimation of vaccine effectiveness to prevent death due to COVID-19 was done indirectly by combining infection and death estimates. In addition, we evaluated the effect of the first dose of viral vector vaccines across time. FINDINGS: From Jan 31, to Sept 14, 2021, 1 282 928 individuals were included, of whom 687 167 (53·6%) were in the rAd26-rAd5 analysis, 358 431 (27·6%) in the ChAdOx1 nCoV-19 analysis, and 237 330 (18·5%) in the BBIBP-CorV analysis. Vaccine effectiveness after two doses was high for all three vaccines, adjusted odds ratio 0·36 (95% CI 0·35-0·37) for rAd26-rAd5, 0·32 (0·31-0·33) for ChAdOx1 nCoV-19, and 0·56 (0·55-0·58) for BBIBP-CorV. After two doses, the effect on deaths was higher than that on risk of infection: adjusted hazard ratio 0·19 (95% CI 0·18-0·21) for rAd26-rAd5, 0·20 (0·18-0·22) for ChAdOx1 nCoV-19, and 0·27 (0·25-0·29) for BBIBP-CorV. The indirectly estimated effectiveness on deaths was 93·1% (95% CI 92·6-93·5) for rAd26-rAd5, 93·7% (93·2-94·3) for ChAdOx1 nCoV-19, and 85·0% (84·0-86·0) for BBIBP-CorV following two doses. First dose effect of viral vector vaccines remained stable over time. INTERPRETATION: The vaccines used in Argentina showed effectiveness in reducing infection and death by SARS-CoV-2 and COVID-19. FUNDING: None.

Seroepidemiologicalmonitoring of SARS-CoV-2 IgG in main railway stations in the city of Buenos Aires, Argentina / Monitoreo seroepidemiológico de igg contra el sars-cov-2 en estaciones ferroviarias cabeceras de la ciudad autónoma de buenos aires, argentina

RESUMEN INTRODUCCIÓN : Los estudios de seroprevalencia permiten monitorear la circulación del SARS-CoV-2 y dan información para evaluar medidas sanitarias. El objetivo fue conocer la proporción y evolución de la seropositividad en puntos de gran circulación de la Ciudad Autónoma de Buenos Aires (CABA) y las características clínico-epidemiológicas de los seropositivos, de abril a octubre de 2020. MÉTODOS : Se realizó un estudio descriptivo transversal de seis rondas de testeos rápidos serológicos y una encuesta de datos epidemiológicos. Se realizó un muestreo por conveniencia en tres estaciones ferroviarias cabeceras de CABA consideradas puntos de alto tránsito bidireccional del Área Metropolitana de Buenos Aires. RESULTADOS : Participaron 7339 personas. La proporción de seropositivos fue 0,6% (IC95%: 0,2-0,9) en la primera ronda y aumentó a 5,6% en la última (IC95%: 4,3-7). Al inicio aumentó la seropositividad en residentes de CABA y de la zona sur de la Región Metropolitana de Buenos Aires. El antecedente de haber presentado síntomas y el de contacto con personas con COVID-19 fueron las únicas variables relacionadas con el resultado de inmunoglobulina G positivo (p <0,05). El 56,1% (n = 97) de los seropositivos no tuvo síntomas. El 78,4% (n = 134) no fue diagnosticado en la etapa aguda. DISCUSIÓN : La seropositividad fue en ascenso en cada ronda, en coincidencia con la situación epidemiológica de la zona de residencia. Las características epidemiológicas como la proporción de seropositivos sin antecedentes de síntomas, reafirman la importancia de las medidas sanitarias poblacionales.

ABSTRACT INTRODUCTION : Seroprevalence studies allow monitoring the circulation of SARS-CoV-2, providing information to evalúate public health measures. The aim of this study was to determine the proportion and evolution of seropositivity in high circulation points in the Ciudad Autónoma de Buenos Aires (CABA) and clinical and epidemiological characteristics of seropositive individuals from April to October 2020. METHODS : A descriptive cross-sectional study was conducted during six rounds, using rapid serological testing together with an epidemiological data survey. A convenience sample was selected in three CABA railway stations considered as high bi-directional traffic points in the Buenos Aires Metropolitan Area (AMBA). RESULTS : 7,339 people participated. The seropositive proportion was 0.6% (95%CI: 0.2-0.9) in the first round, and rose to 5.6% in the last one (95%CI: 4.3-7). Initially, seropositivity increased in CABA residents and those living in the southern part of the Buenos Aires Metropolitan Region. Having presented symptoms and history of contact with COVID-19 cases were the only variables found to be related to positive IgG results (p<0.05). Among seropositive participantes, 56.1% (n=97) had no symptoms and 78.4% (n=134) didn't receive a COVID-19 diagnosis in the acute stage. DISCUSSION : Seropositivity increased between rounds, according to the epidemiological situation in the area of residence. Epidemiological characteristics, such as the proportion of seropositive individuals with no history of symptoms, reaffirm the importance of public health and social measures.

Monitoreo seroepidemiológico de IGG contra el SARS-COV-2 en estaciones ferroviarias cabeceras de la Ciudad Autónoma de Buenos Aires / Seroepidemiological monitoring of SARS-CoV-2 IgG in main railway stations in the city of Buenos Aires, Argentina

INTRODUCCIÓN: Los estudios de seroprevalencia permiten monitorear la circulación del SARS-CoV-2 y dan información para evaluar medidas sanitarias. El objetivo fue conocer la proporción y evolución de la seropositividad en puntos de gran circulación de la Ciudad Autónoma de Buenos Aires (CABA) y las características clínico-epidemiológicas de los seropositivos, de abril a octubre de 2020. MÉTODOS: Se realizó un estudio descriptivo transversal de seis rondas de testeos rápidos serológicos y una encuesta de datos epidemiológicos. Se realizó un muestreo por conveniencia en tres estaciones ferroviarias cabeceras de CABA consideradas puntos de alto tránsito bidireccional del Área Metropolitana de Buenos Aires. RESULTADOS: Participaron 7339 personas. La proporción de seropositivos fue 0,6% (IC95%: 0,2-0,9) en la primera ronda y aumentó a 5,6% en la última (IC95%: 4,3-7). Al inicio aumentó la seropositividad en residentes de CABA y de la zona sur de la Región Metropolitana de Buenos Aires. El antecedente de haber presentado síntomas y el de contacto con personas con COVID-19 fueron las únicas variables relacionadas con el resultado de inmunoglobulina G positivo (p <0,05). El 56,1% (n = 97) de los seropositivos no tuvo síntomas. El 78,4% (n = 134) no fue diagnosticado en la etapa aguda. DISCUSIÓN: La seropositividad fue en ascenso en cada ronda, en coincidencia con la situación epidemiológica de la zona de residencia. Las características epidemiológicas como la proporción de seropositivos sin antecedentes de síntomas, reafirman la importancia de las medidas sanitarias poblacionales.