Persistence of SARS-CoV-2 RNA shedding and infectivity in immunized population: Prospective study along different epidemiological periods in Argentina.

During the pandemic of COVID-19, numerous waves of infections affected the two hemispheres with different impacts on each country. Throughout these waves, and with the emergence of new variants, health systems and scientists have tried to provide real-time responses to the complex biology of SARS-CoV-2, dealing with different clinical presentations, biological characteristics, and clinical impact of these variants. In this context, knowing the extent period in which an infected individual releases infectious viral particles has important implications for public health. This work aimed to investigate viral RNA shedding and infectivity of SARS-CoV-2 beyond 10 days after symptom onset (SO). A prospective multicenter study was performed between July/2021 and February/2022 on 116 immunized strategic personnel with COVID-19 diagnosed by RT-qPCR, with asymptomatic (7%), mild (91%) or moderate disease (2%). At the time of diagnosis, 70% had 2 doses of vaccines, 26% had 2 plus a booster, and 4% had one dose. After day 10 from SO, sequential nasopharyngeal swabs were taken to perform RT-qPCR, viral isolation, and S gene sequencing when possible. Viral sequences were obtained in 98 samples: 43% were Delta, 16% Lambda, 15% Gamma, 25% Omicron (BA.1) and 1% Non-VOC/VOI, in accordance with the main circulating variants at each moment. SARS-CoV-2 RNA was detected 10 days post SO in 57% of the subjects. Omicron was significantly less persistent. Noteworthy, infective viruses could not be isolated in any of the samples. In conclusion, a 10-days isolation period was useful to prevent further infections, and proved valid for the variants studied. Recently, even shorter periods have been applied, as the Omicron variant is prevalent, and worldwide population is largely vaccinated. In the future, facing the possible emergence of new variants and considering immunological status, a return to 10 days may be necessary.

Comparison of Epidemiologic and Clinical COVID-19 Profiles in Children in Argentina, During Circulation of Original and Variant (Alpha, Gamma and Lambda) Strains.

BACKGROUND: Information on the impact of the different variants in children in Latin America is scarce. The objective of this study was to describe epidemiologic and clinical features of COVID-19 infection in children under 18 years of age in Argentina, comparing the periods before and after the circulation of new variants. METHODS: Observational, cross-sectional, multicentric, analytical study. All patients under 18 years of age with confirmed SARS-CoV-2 infection admitted at 22 healthcare centers were included. Two study periods were established: Period 1 (EW10-2020 to EW12-2021) for the Wuhan strain; Period 2 (EW13 to EW35 2021) for Alpha, Gamma, Delta and Lambda variants. FINDINGS: A total of 6330 confirmed cases were included. Period 1: 3575 (56.5%), period 2: 2755 (43.5%). During period 2, a lower number of asymptomatic cases was observed, while general, respiratory and neurologic signs and symptoms increased in all age groups. Oxygen therapy requirement was higher during the first period (36.7% vs 19.1%; P < 0.001). No significant differences were observed in the rates of severe or critical cases (6.3% vs 5,4%; P = 0.102), intensive care admission (2.1% vs 2%; P < 0.656) or case fatality (0.3% vs 0.5 %; P < 0.229). MIS-C cases occurred more frequently during the first period (1.9% vs 1.1%; P = 0.009). INTERPRETATION: The clinical spectrum of COVID-19 in Argentina has evolved. With the emergence of new variants, although the number of asymptomatic cases declined, numbers of severe and critical cases, as well as case fatality rates in children, remained unchanged.

Situación epidemiológica y estado de la respuesta al VIH en la ciudad autónoma de Buenos Aires 2003-2017 / Epidemiological situation and response to HIV in Ciudad Autónoma de Buenos Aires, 2003-2017

El monitoreo de indicadores epidemiológicos es un elemento clave en el fortalecimiento de la respuesta al VIH. OBJETIVO: Se presenta un análisis epidemiológico de las tendencias en indicadores seleccionados en base a las notificaciones de infección reportadas a la Coordinación Salud Sexual, Sida e Infecciones de Transmisión Sexual, dependiente del Ministerio de Salud de la Ciudad Autónoma de Buenos Aires entre 2003 y 2017. MÉTODOS: En dicho análisis se incluyen datos sobre la distribución por sexo e índice de masculinidad, el acceso al diagnóstico de VIH, la distribución por edad al momento del diagnóstico, la cobertura de salud, las vías de transmisión, la tasa de mortalidad por sida, la vigilancia de la transmisión perinatal del VIH y la situación de niños, niñas y adolescentes con VIH. RESULTADOS: Los datos presentados reflejan un perfil metropolitano en el que predomina la transmisión sexual tanto en mujeres como en varones y ponen en evidencia algunas situaciones que precisan un abordaje específico y avalan la importancia de implementar estrategias de prevención diferenciadas de acuerdo a las necesidades de cada grupo poblacional. DISCUSIÓN: La forma en la que se presenta la información muestra una clara intencionalidad de fomentar la interacción entre la epidemiología y la toma de decisiones en salud, a sabiendas de que esa información constituye una herramienta fundamental para la definición y puesta en práctica de políticas públicas. Palabras clave: Epidemiología; VIH; Ciudad de Buenos Aires

Experiencia educativa para estudiantes de medicina de la Universidad de Buenos Aires (UBA) en la evaluación del Calendario Nacional de Vacunación de niños que concurrieron a Hospitales de la Ciudad Autónoma de Buenos Aires (CABA) / Educational experience for medical students at the University of Buenos Aires (UBA) in the evaluation of the National Vaccination Calendar of children who attended hospitals of the Autonomous City of Buenos Aires (CABA)

Objetivos: La participación de alumnos en estudios que evalúan el cumplimiento del programa de Inmunizaciones (PAI) y sus causales representa una experiencia relevante. La evaluación del cumplimiento del PAI permite proponer estrategias para aumentar coberturas.Métodos: Estudio observacional, analítico, transversal. Población: Neonatos a 11 años de edad, realizado en 6 hospitales de la CABA. Período: 1/06-31/12/2014. Participaron estudiantes del internado anual rotatorio capacitados sobre PAI,supervisados por docentes.Criterio de inclusión: Presentar el carné de vacunación, no tener condiciones que impidieran indicación del PAI.Resultados: Encuestas 531. Esquema incompleto o no recibió ninguna vacuna 25,7 por ciento. Se asociaron a incumplimiento las siguientes variables: Edad <1 año, edad materna <28 años, escasa educación materna, embarazo no controlado, ausencia de control de salud, internados, consulta porenfermedad. Análisis multivariado: falta de control de salud: RR 2,1(IC 95 por ciento:1,4-2,9).Como motivo de OPV predominó olvido (71,8 por ciento). Los alumnos refirieron útil su participación. Consideraron positivo aprender a investigar, contacto con pacientes y familiares, trabajar en equipo. Negativo: restó tiempo para estudiar.Conclusiones: Interactuar con la comunidad permitiría eliminar barreras que condicionan OPV. La comunicación es valiosa para lograr este objetivo. La participación supervisada de alumnos fue una experiencia innovadora, al introducirlos en la investigación clínica.

Introduction: The participation of students in research studies is a valuable teaching objective. Particularly evaluating implementation of the National immunization Program and their causal, allowing to propose strategies to increase coverage.Methods: An observational, analytical, crosssectional study. Population: Newborn to 11 years old, conducted in 6 hospitals of Buenos Aires city. Period: 1/06-31/12/2014. Pediatrics students belonging to the pediatric annualtraining in pediatrics, supervised by their teachers. Inclusion criteria: Presentation the vaccination card, have no conditions that would prevent indication of the vaccines.Results: 531 surveys were completed.Incomplete scheme, or no received vaccine 25.7 percent. The following variables were associated with non-compliance schedule: Age <1 year, maternal age <28 years, lowmaternal education, uncontrolled pregnancy, lack of health control, boarding, ambulatory consult for disease. Multivariate analysis: lackof control health: RR 2.1 (95 percent CI: 1.4-2.9).Family forgot vaccinate the child prevailed (71.8 percent). Students reported their participation useful. They considered positive learning how to research, contact with patients andfamilies, teamwork. As negative: Rest time to study.Conclusions: Interacting with the community enable barriers that condition not comply with the scheme. Communication is valuable to achieving this aim. Supervised student participation was an innovative experience to introduce in clinical research.

Estudio de las enfermedades respiratorias por virus Influenza A H1N1 (pH1N1) en niños internados durante el año de la pandemia: Experiencia de 34 centros en la Argentina / Study of respiratory influenza A H1N1 Virus (pH1N1) in hospitalized children in the pandemic year: Experience in 34 centers in Argentina

Introducción. En la Argentina, la pandemia de Influenza A pH1N1 de 2009 provocó cerca de 10 000 casos confirmados con alto impacto en pediatría. Objetivos. Describir las características clínico epidemiológicas y analizar los factores de riesgo de letalidad en niños hospitalizados con infección confirmada por pH1N1. Población y métodos. Se identificaron todas las fichas de casos sospechosos (según Ministerio de Salud) internados en 34 centros y se incluyeron todos los casos confirmados de 0-18 años desde el 1/4/09 al 31/8/09 en un estudio de cohorte retrospectivo. El diagnóstico viral se confirmó por método RT-PCR. Los datos se expresaron en porcentajes, media, mediana, desvío estándar e intervalo intercuartilo (IIC) según correspondiera; y como medida de asociación, Riesgo Relativo (RR), con Intervalo de Confianza 95% (IC95%). Se realizó regresión logística múltiple para determinar los predictores independientes. Resultados. Número total de casos sospechosos: 2367; se realizó PCR al 47,8% (n: 1131) siendo positivos para pH1N1 65,5% (n: 741/1131); 57,2% varones; 61,5% <24 meses, mediana de edad: 14 meses (IIC 6-46 meses); 45,1% con enfermedad subyacente; formas clínicas de presentación más frecuentes: neumonía 39,7% y bronquiolitis 25,8%; letalidad: 5,9% (44/741). Factores de riesgo de letalidad [RR (IC95%)]: enfermedad neurológica [5,00 (2,84-8,81)], enfermedad genética [3,67 (1,58-8,52)], desnutrición [3,07 (1,46-6,48)] y prematurez [2,28 (1,14-4,56)]. Predictor independiente de letalidad: enfermedad neurológica [3,84 (1,81-8,14)]. No se observó asociación significativa entre edad, enfermedad respiratoria crónica, inmunosupresión y coinfección viral con la letalidad. Conclusiones. Casi la mitad de los niños con infección por pH1N1 tenía enfermedad subyacente; la enfermedad neurológica fue un predictor independiente de letalidad.

Introduction. In Argentina, pandemic influenza pH1N1 caused nearly 10,000 confirmed cases with high impact in pediatrics. Objectives. To describe clinical and epidemiological characteristics and analyse the risk factor of lethality in children hospitalized with infection pH1N1 confirmed by PCR Population and methods. We identified all suspected cases (according to Ministry of health) in 34 centers and we included all the confirmed cases of 0-18 years from 1/4/09 to 31/8/09 in a retrospective cohort study. The viral diagnosis was confirmed by RT-PCR method. Data are expres sed in percentages, average, median, standard deviation, and range (IQR) as appropriate; and as a measure of association, relative risk (RR), with 95% confidence interval (95%CI). Multiple logistic regression was conducted to determine the independent risk predictors. Results. Total number of suspected cases were: 2367; PCR was performed to 47.8% (n: 1131) being positive for pH1N1 65.5% (n: 741/1131); 57.2% males; 61.5% <24 months, median age: 14 months (IQR 6-46 months); 45.1% with underlying disease; more frequent clinical pictures were: pneumonia (39,7%) and bronchiolitis 25.8%; Case-fatality rate: 5.9% (44/741). Mortality risk factors were [RR (95%CI)]: neurological disease [5.00 (2.84-8.81)], genetic disease [3.67 (1.58-8.52)], malnutrition [3,07 (1.46-6.48)] and prematurity [2.28 (1.14-4.56)]. Independent mortality predictor: neurological disease [3.84(1.81-8.14)]. No significant association between age, chronic respiratory disease, immunosuppression and viral co-infection with lethality was observed. Conclusions. Almost half of children with pH1N1 infection had underlying disease; the neurological condition was a separate CFR predictor.

[Study of respiratory influenza A H1N1 Virus (pH1N1) in hospitalized children in the pandemic year. Experience in 34 centers in Argentina]. / Estudio de las enfermedades respiratorias por virus Influenza A H1N1 (pH1N1) en niños internados durante el año de la pandemia. Experiencia de 34 centros en la Argentina.

INTRODUCTION: In Argentina, pandemic influenza pH1N1 caused nearly 10,000 confirmed cases with high impact in pediatrics. OBJECTIVES: To describe clinical and epidemiological characteristics and analyse the risk factor of lethality in children hospitalized with infection pH1N1 confirmed by PCR. POPULATION AND METHODS: We identifed all suspected cases (according to Ministry of health) in 34 centers and we included all the confirmed cases of 0-18 years from 1/4/09 to 31/8/09 in a retrospective cohort study. The viral diagnosis was confirmed by RT-PCR method. Data are expressed in percentages, average, median, standard deviation, and range (IQR) as appropriate; and as a measure of association, relative risk (RR), with 95% confidence interval (95%CI). Multiple logistic regression was conducted to determine the independent risk predictors. RESULTS: Total number of suspected cases were: 2367; PCR was performed to 47.8% (n: 1131) being positive for pH1N1 65.5% (n: 741/1131); 57.2% males; 61.5% <24 months, median age: 14 months (IQR 6-46 months); 45.1% with underlying disease; more frequent clinical pictures were: pneumonia (39,7%) and bronchiolitis 25.8%; Case-fatality rate: 5.9% (44/741). Mortality risk factors were [RR (95%CI)]: neurological disease [5.00 (2.84-8.81)], genetic disease [3.67 (1.58-8.52)], malnutrition [3,07 (1.46-6.48)] and prematurity [2.28 (1.14-4.56)]. Independent mortality predictor: neurological disease [3.84 (1.81-8.14)]. No significant association between age, chronic respiratory disease, immunosuppression and viral co-infection with lethality was observed. CONCLUSIONS: Almost half of children with pH1N1 infection had underlying disease; the neurological condition was a separate CFR predictor.

Estudio de las enfermedades respiratorias por virus Influenza A H1N1 (pH1N1) en niños internados durante el año de la pandemia: experiencia de 34 centros en la Argentina / Study of respiratory influenza A H1N1 Virus (pH1N1) in hospitalized children in the pandemic year: experience in 34 centers in Argentina

Introducción. En la Argentina, la pandemia de InfluenzaA pH1N1 de 2009 provocó cerca de 10 000 casos confirmados con alto impacto en pediatría. Objetivos. Describir las características clínico epidemiológicas y analizar los factores de riesgo de letalidad en niños hospitalizados con infección confirmada por pH1N1.Población y métodos. Se identificaron todas las fichas de casos sospechosos (según Ministerio de Salud) internados en 34 centros y se incluyeron todos los casos confirmados de 0-18 años desde el 1/4/09 al 31/8/09 en un estudio de cohorte retrospectivo. El diagnóstico viral se confirmó por método RT-PCR. Los datos se expresaron en porcentajes, media, mediana, desvío estándare intervalo intercuartilo (IIC) según correspondiera; y como medida de asociación, Riesgo Relativo (RR), con Intervalo de Confianza 95 por ciento(IC95 por ciento). Se realizó regresión logística múltiple para determinar los predictores independientes. Resultados. Número total de casos sospechosos: 2367; se realizó PCR al 47,8 por ciento (n: 1131) siendo positivos para pH1N1 65,5 por ciento (n: 741/1131); 57,2 por cientovarones; 61,5 por ciento <24 meses, mediana de edad: 14 meses (IIC 6-46 meses); 45,1 por ciento con enfermedad subyacente; formas clínicas de presentación más frecuentes: neumonía 39,7 por ciento y bronquiolitis 25,8 por ciento; letalidad: 5,9 por ciento (44/741).Factores de riesgo de letalidad [RR (IC95 por ciento)]: enfermedad neurológica [5,00 (2,84-8,81)], enfermedad genética [3,67 (1,58-8,52)], desnutrición [3,07 (1,46-6,48)] y prematurez [2,28 (1,14-4,56)]. Predictor independiente de letalidad: enfermedad neurológica [3,84 (1,81-8,14)]. No se observó asociación significativa entre edad,enfermedad respiratoria crónica, inmunosupresión y coinfección viral con la letalidad. Conclusiones. Casi la mitad de los niños con infección por pH1N1 tenía enfermedad subyacente; la enfermedad neurológica fue un predictor independiente de letalidad.

Introduction. In Argentina, pandemic influenza pH1N1 caused nearly 10,000 confirmed cases with high impact in pediatrics. Objectives. To describe clinical and epidemiological characteristics and analyse the risk factor of lethality in children hospitalized with infectionpH1N1 confirmed by PCR Population and methods. We identified all suspectedcases (according to Ministry of health)in 34 centers and we included all the confirmed cases of 0-18 years from 1/4/09 to 31/8/09 in a retrospective cohort study. The viral diagnosis was confirmed by RT-PCR method. Data are expressed in percentages, average, median, standard deviation, and range (IQR) as appropriate; and as a measure of association, relative risk (RR), with 95% confidence interval (95%CI). Multiple logistic regression was conducted to determine the independent risk predictors. Results. Total number of suspected cases were: 2367; PCR was performed to 47.8% (n: 1131) beingpositive for pH1N1 65.5% (n:741/1131); 57.2% males; 61.5% <24 months, median age: 14 months(IQR 6-46 months); 45.1% with underlying disease; more frequent clinical pictures were: pneumonia (39,7%) and bronchiolitis 25.8%; Case-fatality rate: 5.9% (44/741). Mortality risk factors were [RR (95%CI)]: neurological disease [5.00 (2.84-8.81)], genetic disease [3.67 (1.58-8.52)], malnutrition [3,07 (1.46-6.48)] and prematurity [2.28 (1.14-4.56)]. Independent mortality predictor:neurological disease [3.84 (1.81-8.14)].No significant association between age, chronic respiratory disease, immunosuppression and viral co-infection with lethality was observed.Conclusions. Almost half of children with pH1N1 infection had underlying disease; the neurological condition was a separate CFR predictor.

Pediatric hospitalizations associated with 2009 pandemic influenza A (H1N1) in Argentina.

BACKGROUND: While the Northern Hemisphere experiences the effects of the 2009 pandemic influenza A (H1N1) virus, data from the recent influenza season in the Southern Hemisphere can provide important information on the burden of disease in children. METHODS: We conducted a retrospective case series involving children with acute infection of the lower respiratory tract or fever in whom 2009 H1N1 influenza was diagnosed on reverse-transcriptase polymerase-chain-reaction assay and who were admitted to one of six pediatric hospitals serving a catchment area of 1.2 million children. We compared rates of admission and death with those among age-matched children who had been infected with seasonal influenza strains in previous years. RESULTS: Between May and July 2009, a total of 251 children were hospitalized with 2009 H1N1 influenza. Rates of hospitalization were double those for seasonal influenza in 2008. Of the children who were hospitalized, 47 (19%) were admitted to an intensive care unit, 42 (17%) required mechanical ventilation, and 13 (5%) died. The overall rate of death was 1.1 per 100,000 children, as compared with 0.1 per 100,000 children for seasonal influenza in 2007. (No pediatric deaths associated with seasonal influenza were reported in 2008.) Most deaths were caused by refractory hypoxemia in infants under 1 year of age (death rate, 7.6 per 100,000). CONCLUSIONS: Pandemic 2009 H1N1 influenza was associated with pediatric death rates that were 10 times the rates for seasonal influenza in previous years.

[Congenital tuberculosis. Infrequent presentation of a common disease]. / Tuberculosis congénita. Presentación infrecuente de una enfermedad habitual.

Congenital tuberculosis is a severe rapidly progressive disease which differs from neonatal tuberculosis because patients present tuberculous lesions during their first weeks of life, primary hepatic complex or hepatic caseous granulomas, confirmation of tuberculosis in placenta or in maternal genital tract (uterus or adnexa), and exclusion of birth channel or postnatal exposure. We report a case of a 20 days newborn baby admitted to the neonatal unit with fever, hepatoesplenomegaly, abdominal distension and respiratory symptoms. Abdominal echography showed ascitis, diffuse hepatomegaly and splenomegaly, focal hipoecoical spleen images and portal lymphadenopathy. Thorax X-ray with micronodular infiltrates. Maternal pneumonia with pleural effusion was reported during pregnancy. Empirical treatment was initiated with 4 antituberculous drugs: isoniazid, rifampicin, pyrazinamide and ethambutol suspecting tuberculosis. She died the next day. M. tuberculosis was obtained in a gastric lavage culture, blood cultures and post mortem spleen puncture.