[Effectiveness and safety of COVID-19 vaccines in healthcare workers in Buenos Aires City, Argentina.] / Efectividad y seguridad de las vacunas contra la Covid-19 en trabajadores de la salud en la Ciudad de Buenos Aires, Argentina.

Introduction: COVID-19 vaccination aids pandemic limitation. In Argentina, three vaccines are approved, and healthcare workers are priorized (HCWs). The aim was to determine the effectiveness of COVID-19 vaccines, analyzing change in Immunoglobulin G levels and the incidence of new COVID-19 cases up to 12 months after the second dose. Methods: Prospective cohort of HCWs between March 2021- 2022. COVIDAR IgG test was used to measure antibodies. A mixed-effects model was employed to compare the levels of immunoglobulin G at different time points, Kaplan Meier was used to estimate incident COVID-19 cases. Results: 82 participants were included Adverse events were frequent but mild. All participant showed positive antibody at 12 months. Antibodies levels showed an increase one year after 2nd dose. Sinopharm took a long time to yield positive results. More than half of the people had mild COVID-19 disease. Conclusion: COVID-19 vaccines are safe and effective.

Introducción: La vacunación COVID-19 ayuda a limitar la pandemia. En Argentina, se aprobaron tres vacunas y se priorizó a los trabajadores de la salud (TDS). El objetivo fue determinar la efectividad de las vacunas COVID-19, analizando el cambio en los niveles de Inmunoglobulina G y la incidencia de nuevos casos de COVID-19 hasta 12 meses después de la segunda dosis. Métodos: Cohorte prospectiva de TDS entre marzo de 2021 y 2022. Se utilizó la prueba COVIDAR IgG para medir los anticuerpos. Se empleó un modelo de efectos mixtos para comparar los niveles de inmunoglobulina G en diferentes puntos temporales, se utilizó Kaplan Meier para estimar los casos de COVID-19 incidentes. Resultados: se incluyeron 82 participantes. Los eventos adversos fueron frecuentes pero leves. Todos los participantes mostraron anticuerpos positivos a los 12 meses. Los niveles de anticuerpos mostraron un aumento un año después de la segunda dosis. Sinopharm tardó mucho tiempo en arrojar resultados positivos. Más de la mitad de las personas tuvieron una enfermedad leve de COVID-19. Conclusión: Las vacunas COVID-19 son seguras y efectivas.

Surveillance of Shiga toxin-producing Escherichia coli associated bloody diarrhea in Argentina / Vigilancia de diarrea sanguinolenta asociada a Escherichia coli productor de toxina Shiga en Argentina

Abstract In Argentina, hemolytic uremic syndrome (HUS) caused by Shiga toxin-producing Escherichia coli (STEC-HUS) infection is endemic, and reliable data about prevalence and risk factors have been available since 2000. However, information about STEC-associated bloody diarrhea (BD) is limited. A prospective study was performed during the period October Surveillance; 2018-June 2019 in seven tertiary-hospitals and 18 referral units from different regions, aiming of STEC-HUS cases in the same hospitals and during the same period were also assessed. Twenty-nine (4.1%) of the BD patients were STEC-positive, as determined by the Shiga Toxin Quik Chek (STQC) test and/or the multiplex polymerase chain reaction (mPCR) assay. The highest fre-quencies were found in the Southern region (Neuquén, 8.7%; Bahía Blanca, 7.9%), in children between 12 and 23 month of age (8.8%), during summertime. Four (13.8%) cases progressed to HUS, three to nine days after diarrhea onset. Twenty-seven STEC-HUS in children under 5 years of age (77.8%) were enrolled, 51.9% were female; 44% were Stx-positive by STQC and all by mPCR. The most common serotypes were O157:H7 and O145:H28 and the prevalent geno-types, both among BD and HUS cases, were sfx2a-only or -associated. Considering the endemic behavior of HUS and its high incidence, these data show that the rate of STEC-positive cases is low among BD patients. However, the early recognition of STEC-positive cases is important for patient monitoring and initiation of supportive treatment.

Resumen En Argentina, el síndrome urémico hemolítico asociado a Escherichia coli productor de toxina Shiga (STEC-SUH) es endémico y, desde 2000, de notificación obligatoria. Sin embargo, la información sobre diarrea sanguinolenta (DS) asociada a STEC (DS-STEC) es limitada. Se realizó un estudio prospectivo desde octubre de 2018 hasta junio de 2019 en siete hospitales de tercer nivel y 18 unidades de referencia de diferentes provincias argentinas, con el objetivo de determinar la frecuencia de casos de DS-STEC en 714 niños de 1 a 9 años que tuvieron DS (I) y la tasa de progresión de DS a SUH en dicha cohorte (II). También se evaluó el número y distribución regional de casos de STEC-SUH en los mismos hospitales en dicho período. Veintinueve casos de DS (4,1%) fueron STEC-positivos, determinados por Shiga Toxin Quik Chek (STQC) o PCR múltiple (mPCR). Las frecuencias más altas se encontraron en el sur del área relevada (Neuquén, 8,7%; Bahía Blanca, 7,9%), en niños de 12 a 23 meses (8,8%), en verano. Cuatro casos de DS-STEC (13,8%) progresaron a SUH, de tres a nueve días después del inicio de la diarrea. Se registraron 27 niños con STEC-SUH, estos fueron mayoritariamente <5 anos (77,8%) del sexo femenino (51,9%). El 44% de estos casos fueron Stx-positivos por STQC y todos por mPCR. Los serotipos más comunes fueron O157:H7y O145:H28, y el genotipo predominante fue stx2a, solo o asociado, en DS y SUH. Considerando el comportamiento endémico del SUH y su alta incidencia, estos datos muestran que la tasa de casos de DS-STEC es baja. Sin embargo, su reconocimiento temprano es importante para el seguimiento e inicio del tratamiento de sostén.

Long-term antibody titers variation in unvaccinated patients receiving convalescent plasma or placebo for severe SARS-CoV-2 pulmonary infection.

BACKGROUND: Convalescent plasma (CP) became a prominent treatment in the early stages of the SARS-CoV-2 pandemic. In Argentina, a randomized clinical trial was executed to compare the use of CP in inpatients with severe COVID-19 pneumonia versus placebo. No differences in clinical outcomes or overall mortality between groups were observed. We conducted a cohort study in outpatients enrolled in the trial to describe long-term antibody titer variations between CP and placebo recipients. METHODS: Patients' total SARS-CoV-2 IgG antibodies against spike protein were collected 3, 6 and 12 months after hospital discharge from August 2020 to December 2021. In addition, reinfections, deaths and vaccination status were retrieved. Statistical analysis was performed using antibody geometric mean titers (GMT). All estimations were made considering the date of the trial infusion (placebo or CP) as time 0. RESULTS: From the 93 patients included in the follow-up, 64 had received CP and 29 placebo. We excluded all 12-month measurements because they were collected after the patients' vaccination date. At 90 days post-infusion, patients had an antibody GMT of 8.1 (IQR 7.4-8.1) in the CP group and 8.8 (IQR 8.1-9.1) in the placebo group. At 180 days, both groups had a GMT of 8.1 (IQR 7.4-8.1). No statistical differences in GMT were found between CP and placebo groups at 90 days (p = 0.12) and 180 days (p = 0.25). No patients registered a new COVID-19 infection; one died in the CP group from an ischemic stroke. CONCLUSIONS: No differences were observed in long-term antibody titers in unvaccinated patients that received CP or placebo after severe COVID-19 pneumonia.

Surveillance of Shiga toxin-producing Escherichia coli associated bloody diarrhea in Argentina.

In Argentina, hemolytic uremic syndrome (HUS) caused by Shiga toxin-producing Escherichia coli (STEC-HUS) infection is endemic, and reliable data about prevalence and risk factors have been available since 2000. However, information about STEC-associated bloody diarrhea (BD) is limited. A prospective study was performed during the period October 2018-June 2019 in seven tertiary-hospitals and 18 referral units from different regions, aiming to determine (i) the frequency of STEC-positive BD cases in 714 children aged 1-9 years of age and (ii) the rate of progression of bloody diarrhea to HUS. The number and regional distribution of STEC-HUS cases in the same hospitals and during the same period were also assessed. Twenty-nine (4.1%) of the BD patients were STEC-positive, as determined by the Shiga Toxin Quik Chek (STQC) test and/or the multiplex polymerase chain reaction (mPCR) assay. The highest frequencies were found in the Southern region (Neuquén, 8.7%; Bahía Blanca, 7.9%), in children between 12 and 23 month of age (8.8%), during summertime. Four (13.8%) cases progressed to HUS, three to nine days after diarrhea onset. Twenty-seven STEC-HUS in children under 5 years of age (77.8%) were enrolled, 51.9% were female; 44% were Stx-positive by STQC and all by mPCR. The most common serotypes were O157:H7 and O145:H28 and the prevalent genotypes, both among BD and HUS cases, were stx2a-only or -associated. Considering the endemic behavior of HUS and its high incidence, these data show that the rate of STEC-positive cases is low among BD patients. However, the early recognition of STEC-positive cases is important for patient monitoring and initiation of supportive treatment.

Monitoreo serológico y psicológico en personal de salud durante el comienzo de la pandemia COVID-19 / Serological and psychological monitoring of healthcare workers during the start of the COVID-19 pandemic

Introducción: el personal de salud (PdS) es esencial en la lucha contra el COVID-19. Al inicio de la pandemia, el riesgo de adquirir la enfermedad en este grupo era desconocido. Buscamos estimar incidencia y prevalencia de anticuerpos anti-SARS-CoV-2, y prevalencia de burnout en una cohorte de PdS durante la pandemia COVID-19, así como valorar la prevalencia de burnout y depresión en la cohorte. Materiales y métodos: cohorte prospectiva conformada por médicos que atendían pacientes COVID-19 desde marzo de 2020 hasta enero de 2021, en un hospital de alta complejidad de la ciudad de Buenos Aires. Se evaluó IgM e IgG anti-SARS-CoV-2 quincenalmente durante 3 meses, así como la presencia de síntomas compatibles y factores asociados a la exposición. Se remitió a participantes con alteraciones de la esfera psíquica a contacto con el equipo de salud mental del hospital. Resultados: se incluyeron 52 participantes; de ellos, 31 eran mujeres; mediana de edad 32 años (rango 25-58). La mediana de horas semanales de trabajo autoinformadas fue 48 (IIC [intervalo intercuartil] 40-69,5). Inicialmente todos fueron PCR SARS-CoV-2 negativos en hisopado nasal; 11 (21,50% IC 95%; 9,62-32,53%) tuvieron COVID-19 sintomático con anticuerpos positivos. Los factores con mayor asociación a riesgo de COVID-19 fueron anosmia/disgeusia OR 403,33 (IC 95%; 47,60-3417,02), fiebre OR 172,53 (IC 95%; 28,82-1032,65), mialgias OR 41,97 (IC 95%; 8,08-217,84), conviviente con COVID-19 OR 28,17 (IC 95%; 5,67-179,97). Cerca del 40% presentaba alteraciones en las escalas de medición de burnout o depresión. Discusión: la incidencia hallada coincide con las cifras informadas acerca de personal de salud en la etapa inicial de la pandemia en la Argentina. Otro aspecto similar fue una mayoría de infecciones de curso leve, sin ningún paciente hospitalizado. No obstante, se halló una elevada incidencia de alteraciones de la esfera psíquica, tanto al comienzo como al final del seguimiento. Conclusiones: la incidencia de positivización de anticuerpos anti-SARS-CoV-2 fue cercana al 20%. No evidenciamos infecciones presintomáticas o asintomáticas. En cambio, la prevalencia de burnout y depresión fue elevada. La salud mental es un componente del personal de salud que debe ser priorizado en situaciones futuras de impacto similar. (AU)

Introduction: healthcare personnel are essential in the response against COVID-19. At the beginning of the pandemic the risk of acquiring the disease in this group was unknown. We sought to estimate incidence and prevalence of anti SARS-CoV-2 antibodies, as well as burnout prevalence in a cohort of healthcare staff during the pandemic, as well as assessing the prevalence of burnout and depression in this group. Materials and methods: prospective cohort formed by physicians tending to COVID-19 patients from march 2020 to january 2021 in a high-complexity hospital in the city of Buenos Aires. We evaluated anti SARS-CoV-2 IgM and IgG each 15 days for 3 months as well as the presence of compatible symptoms and factors associated to exposition to the virus. Patients showing signs of burnout and/or depression were referred to proper care by the mental health team in the hospital. Results: we included 52 patients, 31 women, median age was 32 years (range 25 - 58). Median amount of self-reported hours worked each week was 48 (IQR 40 - 69.5). Initially all participants had a negative COVID-19 PCR nasopharyngeal swab; 11 (21.50% CI95% 9.62 - 32.53%) had symptomatic COVID-19 with positive antibodies. Factors showing stronger association with testing positive were anosmia/dysgeusia OR 403.33 (CI95% 47.60-3417.02), fever OR 172.53 (CI95% 28.82 - 1032.65), myalgia OR 41.97 (CI95% 8.08 - 217.84), cohabitation with confirmed COVID-19 case OR 28.17 (CI95% 5.67 - 179.97). Near 40% showed alterations in burnout or depression scales. Discussion: the incidence rate we found was like reported values in the initial stages of the pandemic in Argentina. Another similarity was that all cases were mild; no hospitalization was required for any participant. We found an elevated incidence of alterations in the psychic sphere, both at the beginning and end of the follow up period. Conclusions:the incidence of positive SARS-CoV-2 antibodies was around 20%. No pre or asymptomatic cases were identified. Burnout and depression incidence was high. Mental health is a component that should never be overlooked in similar situations to come. (AU)

The genetic variability of hepatitis B virus subgenotype F1b precore/core gene is related to the outcome of the acute infection.

AIM: To assess the association of viral and host genetic variability with the outcome of acute infection with hepatitis B virus subgenotype F1b (HBV/F1b). METHODS: The cohort consisted of 26 patients with acute HBV/F1b infection who exhibit different outcomes: spontaneous resolution (n = 10), progression to chronic hepatitis (n = 10) and acute liver failure (n = 6). HLA SNPs (rs3077, rs9277542, rs2856718 and rs7453920) were determined. The S gene and core promoter/precore/core region were direct sequenced, and this latter region was also ultra-deep sequenced. Mean number of mutations, mutation rate, Shannon entropy, positive selection sites and mutational patterns of quasispecies were compared between groups. RESULTS: HLA SNPs were associated with spontaneous resolution or progression to chronic hepatitis, but not with the development of acute liver failure. The mean number of mutations in the S gene was similar among the three groups. Patients with spontaneous resolution had the lowest number of mutations, mutation rates and Shannon entropy values in the precore/core compared to the other two groups. Ten positive selection sites mapped on HLA-restricted epitopes were related to progression to chronic hepatitis and acute liver failure. Mutations T1753C, A1762T, G1764A, C1766T, T1768A G1896A, G2092T and T2107C were associated with acute liver failure and progression to chronic hepatitis. CONCLUSION: Highly heterogeneous and complex HBV precore/core carrying specific point mutations, combined with the host HLA background, were associated with a worse clinical outcome of acute HBV/F1b infection.