Evaluation of immunoprotection against coronavirus disease 2019:Novel variants,vaccine inoculation,and complications / 药物分析学报

The strikingly rapidly mutating nature of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)genome has been a constant challenge during the coronavirus disease 2019(COVID-19)pandemic.In this study,various techniques,including reverse transcription-quantitative polymerase chain reaction,antigen-detection rapid diagnostic tests,and high-throughput sequencing were analyzed under different scenarios and spectra for the etiological diagnosis of COVID-19 at the population scale.This study aimed to summarize the latest research progress and provide up-to-date understanding of the methodology used for the evaluation of the immunoprotection conditions against future variants of SARS-CoV-2.Our novel work reviewed the current methods for the evaluation of the immunoprotection status of a specific population(endogenous antibodies)before and after vaccine inoculation(adminis-tered with biopharmaceutical antibody products).The present knowledge of the immunoprotection status regarding the COVID-19 complications was also discussed.Knowledge on the immunoprotection status of specific populations can help guide the design of pharmaceutical antibody products,inform practice guidelines,and develop national regulations with respect to the timing of and need for extra rounds of vaccine boosters.

Associations of SARS-CoV-2 cycle threshold values with age, gender, sample collection setting, and pandemic period

ABSTRACT Cycle threshold (Ct) values in COVID-19 reverse-transcription polymerase chain reaction (RT-PCR) tests estimate the viral load in biological samples. Studies have investigated variables associated with SARS-CoV-2 viral load, aiming to identify factors associated with higher transmissibility. Using the results from tests performed between May/2020-July/2022 obtained from the database of a referent hospital in Sao Paulo, Brazil, we investigated associations between Ct values and patient's age, gender, sample collection setting and pandemic period according to the predominant SARS-CoV-2 variant locally. We also examined variations in Ct values, COVID-19 incidence, mortality, and vaccination coverage over time. The study sample included 42,741 tests. Gender was not significantly associated with Ct values. Age, sample collection setting and the pandemic period were significantly associated with Ct values even after adjustment to the multivariable model. Results showed lower Ct values in older groups, during the Gamma and Delta periods, and in samples collected in emergency units; and higher Ct values in children under 10 years old, home-based tests, during the Omicron period. We found evidence of a linear trend in the association between age and Ct values, with Ct values decreasing as age increases. We found no clear temporal associations between Ct values and local indicators of COVID-19 incidence, mortality, or vaccination between February/2020-November/2022. Our findings suggest that SARS-CoV-2 Ct values, a proxy for viral load and transmissibility, can be influenced by demographic and epidemiological variables.

Comparison of clinical characteristics of wild-type SARS-CoV-2 and Omicron

SUMMARY OBJECTIVE: This study aimed to investigate the effect of mutations by comparing wild-type SARS-CoV-2 and Omicron regarding clinical features in patients with COVID-19. It also aimed to assess whether SARS-CoV-2 cycle threshold value could predict COVID-19 severity. METHODS: A total of 960 wild-type and 411 Omicron variant patients with positive results in SARS-CoV-2 real-time reverse transcriptase polymerase chain reaction test from oropharyngeal and/or nasopharyngeal samples during their hospital admissions were included in this retrospective study. The reference symptoms of the patients were obtained from the hospital database. The correlation between chest computed tomography findings and the "cycle threshold" of patients with wild-type SARS-CoV-2 was assessed. RESULTS: Cough, fever, shortness of breath, loss of taste and smell, and diarrhea were found to be statistically significantly higher (p=0.001; 0.001; 0.001; 0.001; and 0.006; respectively) in the wild-type cohort, while in the Omicron cohort, sore throat and headache were found to be statistically significantly higher (p=0.001 and 0.003, respectively). An inverse relationship was found between chest computed tomography findings and viral load. CONCLUSION: This study revealed that the Omicron variant tended to infect predominantly the upper respiratory tract and showed decreased lung infectivity, and the disease progressed with a milder clinical course. Therefore, the study showed that the tropism of the virus was changed and the viral phenotype was affected. It was also found that SARS-CoV-2 viral load did not predict COVID-19 severity in patients with wild-type SARS-CoV-2.

Cambios en las características clínicas y desenlaces de pacientes hospitalizados por COVID-19 durante dos años de pandemia: experiencia en un hospital venezolano / Changes in clinical characteristics and outcomes of patients hospitalized with COVID-19 during two years of the pandemic: experience in a venezuelan hospital

RESUMEN Objetivos. Determinar los cambios en las características clínicas y desenlaces intrahospitalarios de los pacientes hospitalizados por COVID-19 en un hospital privado de Caracas durante dos años de pandemia. Materiales y métodos. Estudio retrospectivo, observacional, de pacientes hospitalizados por COVID-19. Se investigó la correspondencia entre las olas de ingresos hospitalarios con las variantes circulantes del SARS-CoV-2 en la población general del Distrito Capital y estado Miranda. Resultados. Se incluyeron 1025 pacientes (569 hombres y 456 mujeres), con edad promedio de 62,9 DE: 16,2 años. Cuatro olas de ingresos hospitalarios fueron identificadas: primera (marzo-noviembre 2020) 150/1025 (14,6%) casos; segunda (diciembre-2020 a mayo-2021) 415/1025 (40,5%) casos; tercera (junio-diciembre 2021) 344/1025 (33,6%) casos; cuarta (enero-febrero 2022) 116/1025 (11,3%) casos. La edad promedio fue mayor en la cuarta ola (primera 64,0±15,7, segunda 61,4±15,8, tercera 62,1±16,5, y cuarta ola 68,5±16,4), mientras que la proporción de pacientes masculinos (primera 66,7%, segunda 58,8%, tercera 50,3%, y cuarta 44,8%), los pacientes con enfermedad grave-crítica (primera 65,3%, segunda 57%, tercera 51,7% y cuarta 44,8%), la estadía intrahospitalaria (primera 9,1±6,0, segunda 9,0±7,3, tercera 8,8±7,7, y cuarta 6,9±5,0 días), los ingresos a la UCI (primera 23,3%, segunda 15,7%, tercera 14,0%, y cuarta 11,2%; p=0,027) y la mortalidad (primera 21.8%, segunda 10,7%, tercera 9,1%, y cuarta 7,1%; p<0,001) disminuyeron progresivamente con el tiempo. Conclusiones. Los resultados muestran menor frecuencia de casos severos y mejoría de los desenlaces intrahospitalarios en dos años de pandemia. Es probable que los cambios en las variantes circulantes, las mejoras del manejo de la enfermedad y la vacunación hayan influido sobre estos resultados.

ABSTRACT Objectives. To determine changes in the clinical characteristics and in-hospital outcomes of patients hospitalized for COVID-19 in a private hospital in Caracas during two years of the pandemic. Materials and Methods. Retrospective, observational study of patients hospitalized for COVID-19. We evaluated the correspondence between waves of hospital admissions and circulating variants of SARS-CoV-2 in the general population of the Capital District and Miranda state. Results. A total of 1025 patients (569 men and 456 women) were included, with a mean age of 62.9 SD: 16.2 years. Four waves of hospital admissions were identified: first (March-November 2020) 150/1025 (14.6%) cases; second (December 2020 to May 2021) 415/1025 (40.5%) cases; third (June-December 2021) 344/1025 (33.6%) cases; fourth (January-February 2022) 116/1025 (11.3%) cases. The mean age was higher in the fourth wave (first: 64.0±15.7, second: 61.4±15.8, third: 62.1±16.5, and fourth wave: 68.5±16.4), while the proportion of male patients (first: 66.7%, second: 58.8%, third: 50.3%, and fourth wave: 44.8%), patients with severe-critical illness (first: 65.3%, second: 57%, third: 51.7%, and fourth wave: 44.8%), in-hospital stay (first: 9.1±6.0, second: 9.0±7.3, third: 8.8±7.7, and fourth wave: 6.9±5.0 days), ICU admissions (first: 23.3%, second: 15.7%, third: 14.0%, and fourth wave: 11.2%; p=0.027) and mortality (first: 21. 8%, second: 10.7%, third: 9.1%, and fourth wave: 7.1%; p<0.001) progressively decreased over time. Conclusions. The results show lower frequency of severe cases and improvement of in-hospital outcomes in two years of the pandemic. Changes in circulating variants, improvements in disease management and vaccination are likely to have influenced these results.

Prevention， Treatment， and Recuperation of Infection with SARS-CoV-2 Variants by Traditional Chinese Medicine Based on Idea of Epidemic Prevention of Jiangnan Medical School / 中国实验方剂学杂志

Because of the frequent occurrence of epidemics in Jiangnan since ancient times， the local medical schools have accumulated rich experience in epidemic prevention， among which Yushan medical school， Wumen medical school， and Qiantang medical school are famous. The physicians have inherited the theory in Treatise on Cold Damage Diseases and developed the therapies for febrile diseases. Adhering to the idea of integrating cold and febrile diseases， the physicians in Jiangnan flexibly adapt ZHANG Zhongjing's theory by combining regional climate， patient physique and other factors to explain the pathogenesis， which is of great significance for the prevention and treatment of epidemics. Therefore， traditional Chinese medicine （TCM） has demonstrated good curative effect on coronavirus disease-2019 （COVID-19） in China. However， the SARS-CoV-2 variants （Delta and Omicron） characterized by strong infectivity， pathogenicity， and immune escape capacity keep emerging， which bring great challenges to the global prevention and control of this pandemic. To this end， we studied the ways of Jiangnan medical school for the prevention and treatment of epidemics， reviewed the evolution of TCM treatment protocols for COVID-19， and summarized China's experience in fighting against the emerging SARS-CoV-2 variants. Further， we explored the measures of TCM in treating SARS-CoV-2 variants from prevention， treatment， and rehabilitation according to the theory for epidemic prevention of Jiangnan medical school. This paper provides reference for the prevention and treatment of emerging SARS-CoV-2 variant and facilitates the development of TCM epidemiology.

Replacement of SARS-CoV-2 strains with variants carrying N501Y and L452R mutations in Japan: an epidemiological surveillance assessment

Objective@#Monitoring the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants is important due to concerns regarding infectivity, transmissibility, immune evasion and disease severity. We evaluated the temporal and regional replacement of previous SARS-CoV-2 variants by the emergent strains, Alpha and Delta.@*Methods@#We obtained the results of polymerase chain reaction screening tests for variants conducted in multiple commercial laboratories. Assuming that all previous strains would be replaced by one variant, the new variant detection rate was estimated by fitting a logistic growth model. We estimated the transmission advantage of each new variant over the pre-existing virus strains.@*Results@#The variant with the N501Y mutation was first identified in the Kinki region in early February 2021, and by early May, it had replaced more than 90% of the previous strains. The variant with the L452R mutation was first detected in the Kanto-Koshin region in mid-May, and by early August, it comprised more than 90% of the circulating strains. Compared with pre-existing strains, the variant with the N501Y mutation showed transmission advantages of 48.2% and 40.3% in the Kanto-Koshin and Kinki regions, respectively, while the variant with the L452R mutation showed transmission advantages of 60.1% and 71.9%, respectively.@*Discussion@#In Japan, Alpha and Delta variants displayed regional differences in the replacement timing and their relative transmission advantages. Our method is efficient in monitoring and estimating changes in the proportion of variant strains in a timely manner in each region.

COVID-19 and isolation: Risks and implications in the scenario of new variants

Abstract With the emergence of new variants of SARS-CoV-2, questions about transmissibility, vaccine efficacy, and impact on mortality are important to support decision-making in public health measures. Modifications related to transmissibility combined with the fact that much of the population has already been partially exposed to infection and/or vaccination, have stimulated recommendations to reduce the isolation period for COVID-19. However, these new guidelines have raised questions about their effectiveness in reducing contamination and minimizing impact in work environments. Therefore, a collaborative task force was developed to review the subject in a non-systematic manner, answering questions about SARS-CoV-2 variants, COVID-19 vaccines, isolation/quarantine periods, testing to end the isolation period, and the use of masks as mitigation procedures. Overall, COVID-19 vaccines are effective in preventing severe illness and death but are less effective in preventing infection in the case of the Omicron variant. Any strategy that is adopted to reduce the isolation period should take into consideration the epidemiological situation of the geographical region, individual clinical characteristics, and mask for source control. The use of tests for isolation withdrawal should be evaluated with caution, due to results depending on various conditions and may not be reliable.

COVID-19 vaccine candidates and vaccine development platforms available worldwide / 药物分析学报

The pandemic caused by the worldwide spread of the coronavirus,which first appeared in 2019,has been named coronavirus disease 19 (COVID-19).More than 4.5 million deaths have been recorded due to the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2),according to the World Health Organization.COVID-19 Dashboard in September 2021.Apart from the wildtype,other variations have been successfully transmitted early in the outbreak although they were not discovered until March 2020.Modifications in the SARS-CoV-2 genetic material,such as mutation and recombi-nation,have the ability to modify the viral life span,along with transitivity,cellular tropism,and symptom severity.Several processes are involved in introducing novel vaccines to the population,including vaccine manufacturing,preclinical studies,Food and Drug Administration permission or cer-tification,processing,and marketing.COVID-19 vaccine candidates have been developed by a number of public and private groups employing a variety of strategies,such as RNA,DNA,protein,and viral vectored vaccines.This comprehensive review,which included the most subsequent evidence on unique features of SARS-CoV-2 and the associated morbidity and mortality,was carried out using a systematic search of recent online databases in order to generate useful knowledge about the COVID-19 updated versions and their consequences on the disease symptoms and vaccine development.