Immunogenicity induced by the use of alternative vaccine platforms to deal with vaccine shortages in a low- to middle-income country: Results of two randomized clinical trials.

BACKGROUND: Shortages of component two of Sputnik V vaccine (rAd5) are delaying the possibility of achieving full immunisation. The immunogenic response associated with the use of alternative schemes to complete the scheme was not explored. METHODS: We did two non-inferiority randomized clinical trials with outcomes measures blinded to investigators on adults aged 21-65 years, vaccinated with a single dose of rAd26 ≥ 30 days before screening and no history of SARS-CoV-2. Participants were assigned (1:1:1:1:1) to receive either rAd5; ChAdOx1; rAd26; mRNA-1273 or BBIBP-CorV. The primary endpoint was the geometric mean ratio (GMR) of SARS-CoV-2 anti-spike IgG concentration at 28 days after the second dose, when comparing rAd26/rAd5 with rAd26/ChAdOx1, rAd26/rAd26, rAd26/mRNAmRNA-1273 and rAd26/BBIBP-CorV. Serum neutralizing capacity was evaluated using wild type SARS-CoV-2 reference strain 2019 B.1. The safety outcome was 28-day rate of serious adverse. The primary analysis included all participants who received ≥ 1 dose. The studies were registered with NCT04962906 and NCT05027672. Both trials were conducted in Buenos Aires, Argentina. FINDINGS: Between July 6 and August 3, 2021, 540 individuals (age 56·7 [SD 7·3]; 243 (45%) women) were randomly assigned to received rAd5 (n=150); ChAdOx1 (n=150); rAd26 (N=87); mRNAmRNA-1273 (n=87) or BBIBP-CorV (n=65). 524 participants completed the study. As compared with rAd26/rAd5 (1·00), the GMR (95%CI) at day 28 was 0·65 (0·51-0·84) among those who received ChAdOx1; 0·47 (0·34-0·66) in rAd5; 3·53 (2·68-4·65) in mRNA-1273 and 0·23 (0·16-0·33) in BBIBP-CorV. The geometric mean (IU/ml) from baseline to day 28 within each group increased significantly with ChAdOx1 (4·08 (3·07-5·43)); rAd26 (2·69 (1·76-4·11)); mRNA-1273 (21·98 (15·45-31·08)) but not in BBIBP-CorV (1·22 (0·80-1·87)). INTERPRETATION: Except for mRNA-1273 which proved superior, in all other alternatives non-inferiority was rejected. Antibody concentration increased in all non-replicating viral vector and RNA platforms. FUNDING: The trials were supported (including funding, material support in the form of vaccines and testing supplies) by the Buenos Aires City Government.

Antimicrobial stewardship programs in adult intensive care units in Latin America: Implementation, assessments, and impact on outcomes.

OBJECTIVE: To assess the impact of antimicrobial stewardship programs (ASPs) in adult medical-surgical intensive care units (MS-ICUs) in Latin America. DESIGN: Quasi-experimental prospective with continuous time series. SETTING: The study included 77 MS-ICUs in 9 Latin American countries. PATIENTS: Adult patients admitted to an MS-ICU for at least 24 hours were included in the study. METHODS: This multicenter study was conducted over 12 months. To evaluate the ASPs, representatives from all MS-ICUs performed a self-assessment survey (0-100 scale) at the beginning and end of the study. The impact of each ASP was evaluated monthly using the following measures: antimicrobial consumption, appropriateness of antimicrobial treatments, crude mortality, and multidrug-resistant microorganisms in healthcare-associated infections (MDRO-HAIs). Using final stewardship program quality self-assessment scores, MS-ICUs were stratified and compared among 3 groups: ≤25th percentile, >25th to <75th percentile, and ≥75th percentile. RESULTS: In total, 77 MS-ICU from 9 Latin American countries completed the study. Twenty MS-ICUs reached at least the 75th percentile at the end of the study in comparison with the same number who remain within the 25th percentile (score, 76.1 ± 7.5 vs 28.0 ± 7.3; P < .0001). Several indicators performed better in the MS-ICUs in the 75th versus 25th percentiles: antimicrobial consumption (143.4 vs 159.4 DDD per 100 patient days; P < .0001), adherence to clinical guidelines (92.5% vs 59.3%; P < .0001), validation of prescription by pharmacist (72.0% vs 58.0%; P < .0001), crude mortality (15.9% vs 17.7%; P < .0001), and MDRO-HAIs (9.45 vs 10.96 cases per 1,000 patient days; P = .004). CONCLUSION: MS-ICUs with more comprehensive ASPs showed significant improvement in antimicrobial utilization.

Evaluation of a COVID-19 Vaccine Campaign and SARS-CoV-2 Infection and Mortality Among Adults Aged 60 Years And Older in a Middle-Income Country.

Importance: Although there are reports of COVID-19 vaccine implementation in real-world populations, these come from high-income countries or from experience with messenger RNA technology vaccines. Data on outcomes of vaccine deployment in low- or middle-income countries are lacking. Objective: To assess whether the pragmatic application of the 3 COVID-19 vaccines available in Argentina, 2 of which have no reports of evaluation in real-world settings to date, were associated with a reduction in morbidity, all-cause mortality, and mortality due to COVID-19. Design, Setting, and Participants: This cohort study used individual and ecological data to explore outcomes following vaccination with rAd26-rAd5, ChAdOx1, and BBIBP-CorV. To correct for differences in exposure times, results are shown using incidence density per 100 000 person-days from the start of the vaccination campaign (December 29, 2020) to the occurrence of an event or the end of follow-up (May 15, 2021). Participants included 663 602 people aged at least 60 years residing in the city of Buenos Aires, Argentina. Statistical analysis was performed from June 1 to June 15, 2021. Main Outcomes and Measures: Diagnosis of COVID-19 confirmed by reverse transcription-polymerase chain reaction, death from all causes, and death within 30 days of a diagnosis of COVID-19. Poisson regression models were fitted to estimate associations with all 3 outcomes. Results: Among 663 602 residents of the city of Buenos Aires included in the study, 540 792 (81.4%) were vaccinated with at least 1 dose, with 457 066 receiving 1 dose (mean [SD] age, 74.5 (8.9) years; 61.5% were female [n = 281 284]; 68.0% [n = 310 987] received the rAd26-rAd5 vaccine; 29.5% [n = 135 036] received ChAdOx1; 2.4% [n = 11 043] received BBIBP-CorV) and 83 726 receiving 2 doses (mean [SD] age, 73.4 [6.8] years; 63.5% were female [n = 53 204]). The incidence density of confirmed COVID-19 was 36.25 cases/100 000 person-days (95% CI, 35.80-36.70 cases/100 000 person-days) among those who did not receive a vaccine, 19.13 cases/100 000 person-days (95% CI, 18.63-19.62 cases/100 000 person-days) among those who received 1 dose, and 4.33 cases/100 000 person-days (95% CI, 3.85-4.81 cases/100 000 person-days) among those who received 2 doses. All-cause mortality was 11.74 cases/100 000 person-days (95% CI, 11.51-11.96 cases/100 000 person-days), 4.01 cases/100 000 person-days (95% CI, 3.78-4.24 cases/100 000 person-days) and 0.40 cases/100 000 person-days (95% CI, 0.26-0.55 cases/100 000 person-days). COVID-19-related-death rate was 2.31 cases/100 000 person-days (95% CI, 2.19-2.42 cases/100 000 person-days), 0.59 cases/100 000 person-days (95% CI, 0.50-0.67 cases/100 000 person-days), and 0.04 cases/100 000 person-days (95% CI, 0.0-0.09 cases/100 000 person-days) among the same groups. A 2-dose vaccination schedule was associated with an 88.1% (95% CI, 86.8%-89.2%) reduction in documented infection, 96.6% (95% CI, 95.3%-97.5%) reduction in all-cause death, and 98.3% (95% CI, 95.3%-99.4%) reduction in COVID-19-related death. A single dose was associated with a 47.2% (95% CI, 44.2%-50.1%) reduction in documented infection, 65.8% (95% CI, 61.7%-69.5%) reduction in all-cause death, and 74.5% (95% CI, 66%-80.8%) reduction in COVID-19-related death. Conclusions and Relevance: This study found that within the first 5 months after the start of the vaccination campaign, vaccination was associated with a significant reduction in COVID-19 infection as well as a reduction in mortality.

Use of alternative care sites during the COVID-19 pandemic in the city of Buenos Aires, Argentina.

OBJECTIVES: In large cities, where a large proportion of the population live in poverty and overcrowding, orders to stay home to comply with isolation requirements are difficult to fulfil. In this article, the use of alternative care sites (ACSs) for the isolation of patients with confirmed COVID-19 or persons under investigation (PUI) in the City of Buenos Aires during the first wave of COVID-19 are described. STUDY DESIGN: This is a cross-sectional study. METHODS: All patients with COVID-19 and PUI with insufficient housing resources who could not comply with orders to stay home and who were considered at low clinical risk in the initial triage were referred to refurbished hotels in the City of Buenos Aires (Ciudad Autónoma de Buenos Aires [CABA]). ACSs were divided into those for confirmed COVID-19 patients and those for PUI. RESULTS: From March to August 2020, there were 58,143 reported cases of COVID-19 (13,829 of whom lived in slums) in the CABA. For COVID-19 positive cases, 62.1% (n = 8587) of those living in slums and 21.4% (n = 9498) of those living outside the slums were housed in an ACS. In total, 31.1% (n = 18,085) of confirmed COVID-19 cases were housed in ACSs. In addition, 7728 PUI were housed (3178 from the slums) in an ACS. The average length of stay was 9.0 ± 2.5 days for patients with COVID-19 and 1.6 ± 0.7 days for PUI. For the individuals who were housed in an ACS, 1314 (5.1%) had to be hospitalised, 56 were in critical care units (0.22%) and there were 27 deaths (0.1%), none during their stay in an ACS. CONCLUSIONS: Overall, about one-third of all people with COVID-19 were referred to an ACS in the CABA. For slum dwellers, the proportion was >60%. The need for hospitalisation was low and severe clinical events were rare. This strategy reduced the pressure on hospitals so their efforts could be directed to patients with moderate-to-severe disease.

[Multicenter study of adherence to guidelines on surgical prophylaxis and the determinants of non-adherence in ArgentinaEstudo multicêntrico sobre a adesão a diretrizes de profilaxia cirúrgica e seus determinantes na Argentina]. / Estudio multicéntrico de adherencia a guías de profilaxis quirúrgica y sus determinantes en Argentina.

OBJECTIVE: Evaluate the level of adherence to guidelines on surgical prophylaxis in health facilities in Argentina and the determinants of non-adherence. METHODS: Cross-sectional multicenter study in 35 centers in Argentina. The level of adherence to guidelines and the forms of non-adherence were determined and these were compared based on the characteristics of the indicated antibiotic, anesthesiologist, surgery, and facility, as well as patient age. An adjusted logistic regression model was used. RESULTS: A total of 1,083 surgical procedures were reviewed. Adherence to guidelines was 67%. The most frequent forms of non-adherence were: incorrect antibiotic (28.9%), unnecessary prophylaxis (25.5%), and prolonged prophylaxis (24.4%). Adherence to guidelines was higher in persons under 18 years of age (84.9% compared to 65.5%, p < 0.001). According to the type of health coverage (social welfare, private insurance, public coverage, or community coverage), adherence was 33.3%, 64.4%, 78.8%, and 83.3%, respectively; p < 0.001. According to population (maternal and child, pediatric, specific pathologies, and general pathologies), adherence was 97.9%, 97.2%, 89.4%, and 63.2%, respectively; p < 0.001. Adherence was highest in neurosurgery (91.1%), obstetrics (82.4%), and cardiovascular surgery (72.9%), and lowest in otorhinolaryngology (47.8%), ophthalmology (50%), and urology (55.9%) (p < 0.001). The adjusted analysis showed the highest adherence to guidelines in persons under 18 (odds ratio [OR]: 4.97; 95% confidence interval [CI 95]: 1.13-21.80); emergency surgery (OR: 2.18; CI 95: 1.11-4.26); and public, private, and community facilities (OR: 9.35; CI 95: 3.85-22.70). Adherence was also higher in facilities for maternal and child care and specific pathologies (OR: 10.52; CI 95, 1.30-85.12), cardiovascular surgery, neurosurgery, obstetrics (OR: 2.73; CI 95: 1.55-4.78), and facilities with programs to optimize the use of antimicrobial drugs (OR 1.95; CI 95, 1.10-3.45). CONCLUSIONS: Adherence to guidelines was 67%. Incorrect, unnecessary, and prolonged use of antibiotics were the most frequent forms of non-adherence. Adherence was higher with younger patients, where programs exist to optimize the use of antimicrobial drugs, where there is private or public health coverage, with the pediatric population, for specific pathologies, in emergency surgery, and in certain specialties.

OBJETIVO: Avaliar o nível de adesão às diretrizes (AD) de profilaxia cirúrgica em instituições de saúde da Argentina e os determinantes da não adesão (NA). MÉTODOS: Estudo multicêntrico transversal realizado em 35 centros na Argentina. Determinamos o nível de AD e as formas de NA, comparados segundo as características das seguintes variáveis: indicação antibiótica, anestesista, cirurgia, instituição e idade do paciente. Aplicamos um modelo de regressão logística ajustado. RESULTADOS: Revisamos um total de 1083 procedimentos cirúrgicos. A taxa de AD foi de 67%. As formas mais frequentes de NA foram: antibiótico incorreto (28,9%), profilaxia desnecessária (25,5%) e profilaxia prolongada (24,4%). A AD foi mais elevada em pacientes com menos de 18 anos (84,9% vs. 65,5%, p<0,001); também houve variações segundo o tipo de instituição (instituição de seguridade social, privada, pública ou comunitária, com adesão de 33,3%, 64,4%, 78,8% e 83,3%, respectivamente; p<0,001) e segundo a população (materno-infantil, pediátrica, com patologia específica ou geral, com adesão de 97,9%, 97,2%, 89,4% e 63,2%, respectivamente; p<0,001). A AD foi maior em neurocirurgia (91,1%), obstetrícia (82,4%) e cirurgia cardiovascular (72,9%) e menor em otorrinolaringologia (47,8%), oftalmologia (50%) e urologia (55,9%) (p<0,001). A análise ajustada mostrou uma AD mais elevada em pacientes com menos de 18 anos (odds ratio [OR]: 4,97, intervalo de confiança de 95% [IC95%]: 1,13-21,80), em cirurgias de emergência (OR: 2,18, IC95%: 1,11-4,26) e em instituições públicas, privadas ou comunitárias (OR: 9,35, IC95%: 3,85-22,70). A AD também foi superior em instituições para população materno-infantil ou para populações específicas (OR: 10,52; IC95%: 1,30-85,12), cirurgia cardiovascular, neurocirurgia, obstetrícia (OR: 2,73; IC95%: 1,55-4,78) e em instituições com programas para a otimização do uso de antimicrobianos (OR: 1,95; IC95%: 1,10-3,45). CONCLUSÕES: A AD foi de 67%; as formas mais frequentes de NA foram o uso incorreto, desnecessário e prolongado de antibióticos. A AD foi maior em pacientes mais jovens, em instituições com programas para a otimização do uso de antimicrobianos, em instituições privadas ou públicas e em populações pediátricas ou específicas, nos procedimentos cirúrgicos de emergência e em certas especialidades.

Viral hepatitis and Treponema pallidum prevalence in persons who underwent premarital blood tests in Argentina.

The objective of this study was to estimate the prevalence of different serological markers of hepatitis A, B and C viruses and Treponema pallidum among the adult population of Argentina. To achieve this, adults who attended health services for premarital exams (which are mandatory and includes screening for syphilis) were recruited. A cross-sectional study was designed with a cluster sampling strategy. Couples who attended selected health services for premarital screening between 2013 and 2014 in Buenos Aires, Cordoba, Mendoza and Santa Fe provinces were included. A total of 3833 individuals were recruited. Anti-HAV prevalence was 63.9%, anti-HCV 0.3%, anti-HBc (without HBsAg) 1.9%, HBsAg 0.3%, and T pallidum 0.8%. Anti-HAV was higher among older participants, foreigners and those from the lower strata. HBV increased with age and was higher among foreigners and those with lower formal educational level. Anti-HCV frequency increased with age. Premarital screening of viral hepatitis could constitute an instance of diagnosis, vaccination and inclusion in care of those in need. Results from this study will allow the national hepatitis programs to design public policies in order to diminish the impact of these infections on the population.

Elaboración de criterios epidemiológicos para estratificar por departamento poblacional de dengue grave / Development of Epidemiological Criteria to stratify by Department the Population Risk of Severe Dengue

: INTRODUCCIÓN: En Argentina desde 1998 ocurrieron brotes de dengue todos los años excepto 2001 y 2005 en diferentes áreas, en 15 jurisdicciones, con identificación de los 4 serotipos. El objetivo de este estudio fue identificar poblaciones con mayor riesgo de desarrollar formas graves de la enfermedad como insumo para la posible introducción de una estrategia de prevención. METODOS: Se realizó un estudio retrospectivo descriptivo de los casos de dengue confirmados autóctonos a partir de publicaciones oficiales, notificaciones al SNVS e información aportada por las áreas de epidemiología provinciales. Se elaboró una estratificación del riesgo de dengue grave por departamento para el período 1998-2018. RESULTADOS: Se elaboraron 5 criterios de estratificación de riesgo: registro de casos autóctonos en al menos 2 de los 5 cinco últimos años, registro de 2 o más serotipos causantes del 10% o más de los casos cada uno, incidencia acumulada mayor a 500 casos por 100 mil habitantes, incidencia acumulada mayor a 5 casos por mil menores de 15 años y registro de casos graves o fallecidos. Se obtuvieron 60 departamentos con 1 criterio, 19 con 2, 8 con 3, 4 con 4, 1 con 5 y 129 no cumplieron criterios. DISCUSION: Solo 13 departamentos sumaron 3 criterios o más, resultado del predominio de DENV-1, la baja incidencia en menores de 15 años y el bajo número de casos graves y fatales. La estratificación del riesgo poblacional con criterios de registro sistemático se orienta a obtener una herramienta de evaluación de los escenarios de dengue que puedan presentarse en el futuro.

Desigualdades sociales en la mortalidad por causas externas en la ciudad de Buenos Aires. Año 2005 / Social inequalities in mortality in Buenos Aires city due to external causes. Year 2005

Introducción: Este estudio se inscribe dentro de las actividades de análisis de situación de salud que realiza el Departamento de Epidemiología (DGAAPS) del Ministerio de Salud de la Ciudad de Buenos Aires. Objetivo: Describir las desigualdades sociales existentes en la mortalidad por causas externas en residentes ocurridas durante el año 2005. Materiales y Métodos: Estudio descriptivo de corte transversal. Se trabajó con datos de Mortalidad de la DGEyC ­GCBA- 2005. Resultados: Se aplicaron índices de efecto e impacto y se observó una brecha de desigualdad (riesgo atribuible poblacional (IRD): 2,2) (IDP: 28) (RAP: 6), (RAP% 16,6%). La asociación entre NBI y la mortalidad por causas externas resultó estadísticamente significativa (R2=0,67). La concentración de la mortalidad fue mayor entre la población más pobre. (IC: -1,24). Conclusiones: La mortalidad por causas externas en la ciudad evidencia brechas de desigualdad El componente del incendio de Cromañon no es ajeno a esta circunstancia. Las tasas brutas y ajustadas muestran estas diferencias. Existen desigualdades sociales en esta dimensión de la mortalidad de modo que a mayor pobreza, mayores tasas ajustadas. Las mayores diferencias se ubican entre los diagnósticos de «otros accidentes ¼ y «agresiones¼ y estas diferencias son estadísticamente significativas.

Introduction: This study falls within the health situation analysis practice performed by the Epidemiology Department (DGAAPS) of Buenos Aires City Ministry of Health. Objective: To describe the existing social inequalities in the mortality of residents due to external causes that took place in the year 2005. Materials and Methods: This is a descriptive, cross-sectional study. Mortality data from DGEyC ­GCBA- 2005 were used. Results: By comparing effect and impact indices, an increase in inequality is observed (IRD: 1.8 in the year 2004 to 2.2 in the year 2005, IDP: 19 in the year 2004 to 28 in the year 2005, RAP: 4 in the year 2004 to 6 in the year 2005, RAP: 12% in the year 2004 to 16.6% in the year 2005). The association between NBI and mortality due to external causes is statistically significant (R2 = 0,67). Mortality concentration was higher in 2005 among the poorest population. (IC: -0.097 in the year 2004 to ­ 1.24 in the year 2005). Conclusions: Mortality due to external causes in Buenos Aires City has slightly increased in the last year. The component of the fire at the disco Cromañon is not alien to this circumstance. Gross and adjusted rates show these differences. There are social inequalities in this dimension of mortality, thus the greater the poverty the higher the adjusted rates are. The greatest differences are within the diagnosis of «other accidents¼ and « aggressions¼ and such differences are statistically significant.