Evaluating the real-world vaccine effectiveness using a regression discontinuity design / 中华流行病学杂志

Estimating the actual real-world effectiveness of the vaccine is an essential part of the post-marketing evaluation. This regression discontinuity design (RDD) using observational data is designed to quantify the effect of an intervention when eligibility for the intervention is based on a defined cutoff as age, making it suited to estimate vaccine effects. This approach can avoid the high cost and ethical issues; overcome difficulties in the organization and practice process in randomized controlled trials, which leads to a higher level of causal inference evidence and more realistic results. Here, we describe key features of RDD in general, and then specific scenarios, with examples, to illustrate that RDD are an essential tool for advancing our understanding of vaccine effects.

Respuesta immune humoral asociada a las vacunas contra SARS-CoV-2 en pacientes con artritis reumatoidea: datos del registro SAR-CoVAC / Humoral immune response associated to the vaccines against SARS-CoV-2 in patients with rheumatic arthritis: data from the SAR-CoVAC registry

Introducción: la artritis reumatoidea (AR) y los tratamientos indicados para su manejo pueden afectar la respuesta a la vacuna para SARS-CoV-2. Sin embargo, aún no se cuenta con datos locales. Objetivos: evaluar la respuesta humoral de la vacuna para SARS-CoV-2 y su seguridad en esta población. Materiales y métodos: estudio observacional. Se incluyeron pacientes ≥18 años, con AR ACR/EULAR 2010 que recibieron la vacunación para SARS-CoV-2. Detección de IgG anti-proteína S (kit COVIDAR). Resultados: se incluyeron 120 pacientes con AR. El 24,4% recibió tratamiento con glucocorticoides, 50,9% drogas biológicas y 13,3% inhibidores de JAK (janus kinases). El 6% había tenido infección por SARS-CoV-2 previamente. La vacuna más utilizada en la primera dosis fue Sputnik V (52,9%). El 25% recibió esquemas heterólogos. Luego de la primera dosis, el 59% presentó una prueba no reactiva o indeterminada, y un 18% luego de la segunda dosis. La aplicación de esquemas homólogos de vacuna Sinopharm (63,6% vs 13,3%, p<0,0001), y el uso de abatacept (27,3% vs 5,1%, p=0,005) y rituximab (18,2% vs 0%, p=0,001) al momento de la vacunación se asociaron a un resultado no reactivo o indeterminado. Conclusiones: similar a lo reportado en otras poblaciones internacionales, en esta cohorte, dos de cada 10 pacientes no desarrollaron anticuerpos. Una menor respuesta se asoció con la vacuna Sinopharm y al tratamiento con abatacept y rituximab.

Introduction: rheumatoid arthritis (RA) and its treatments can affect the response to the SARS-CoV-2 vaccine. However, we still do not have local data. Objectives: to evaluate the humoral response of the SARS-CoV-2 vaccine and its safety in this population. Materials and methods: observational study. Patients ≥18 years of age, with RA ACR/EULAR 2010 who had received vaccination for SARS-CoV-2 were included. Detection of anti-protein S IgG (COVIDAR Kit). Results: a total of 120 patients with RA were included. A quarter was receiving glucocorticoids, 50.9% biological drugs and 13.3% JAK inhibitors (janus kinases). Only 6% had a history SARS-CoV-2 infection. The most used vaccine was Sputnik V (52.9%) and 25% received mixed regimenes. After the first dose, 59% had a non-reactive or indeterminate test, and after the second, 18% were still having this result. The application of homologous Sinopharm vaccine regimen (63.6% vs 13.3%, p<0.0001) and the use of abatacept (27.3% vs 5.1%, p=0.005) and rituximab (18.2% vs 0%, p=0.001) at vaccination was associated with a non-reactive or indeterminate result. Conclusions: similar to other international populations, in this cohort, two out of 10 patients did not develop antibodies. A lower response was associated with the Sinopharm vaccine and treatment with abatacept and rituximab.

Reinfection rates among patients previously infected by SARS-CoV-2: systematic review and meta-analysis / 中华医学杂志(英文版)

BACKGROUND@#Asymptomatic or symptomatic infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be followed by reinfection. The protection conferred by prior infection among coronavirus disease 2019 (COVID-19) patients is unclear. We assessed the incidence of SARS-CoV-2 reinfection and the protection effect of previous infection against reinfection.@*METHODS@#We searched PubMed, EMBASE, Cochrane, Scopus, Web of Science, and ClinicalTrials.gov for publications up until the end date of May 1, 2021. The reinfection rate of recovered patients and the protection against reinfection were analyzed using meta-analysis.@*RESULTS@#Overall, 19 studies of 1096 reinfection patients were included. The pooled reinfection rate was 0.65% (95% confidence interval [CI] 0.39-0.98%). The symptomatic reinfection rate was a bit lower (0.37% [95% CI 0.11-0.78%], I2 = 99%). The reinfection rate was much higher in high-risk populations (1.59% [95% CI 0.30-3.88%], I2 = 90%). The protection against reinfection and symptomatic reinfection was similar (87.02% [95% CI 83.22-89.96%] and 87.17% [95% CI 83.09-90.26%], respectively).@*CONCLUSIONS@#The rate of reinfection with SARS-CoV-2 is relatively low. The protection against SARS-CoV-2 after natural infection is comparable to that estimated for vaccine efficacy. These data may help guide public health measures and vaccination strategies in response to the COVID-19 pandemic. High-quality clinical studies are needed to establish the relevant risk factors in recovered patients.

Considerations on vaccines and immunization against COVID-19 for epidemic control in China / 中华预防医学杂志

The Delta variant of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused a new global wave of the Coronavirus Disease 2019 (COVID-19) pandemic. COVID-19 vaccines currently available in China show high effectiveness against severe illness and death. However, transmission of the virus is not fully stopped by vaccination alone, therefore, integrated vaccination and non-pharmacological interventions is necessary to prevent and control the epidemic in the near future. Further expanded vaccine coverage of primary doses as well as booster shots in China's domestic population are needed to reduce severe illness and death. In order to provide evidence necessary for adjusting and optimizing immunization strategies and pandemic control measures, it is essential to conduct research on vaccine effectiveness against emerging variants, persistence of vaccine-induced protection, surveillance of adverse event following immunization with large-scale vaccine use, and modelling studies on strategic combinations of vaccination and non-pharmacological interventions.