SARS-CoV-2 Variant Determination Through SNP Assays in Samples From Industry Workers From Rio de Janeiro, Brazil

An institutional COVID-19 initiative: creation of a biobank and serological data analysis in pre- and post-vaccination cohorts

The COVID-19 pandemic has left a legacy in the management of health emergencies, but sentinel surveillance was relatively underused, despite its significant role in decision-making during epidemics. Here we describe a sentinel surveillance for anti-SARS-CoV-2 serology carried out on a cohort of 395 individuals at a Brazilian institution, from October 2020 to December 2022. A total of 1,507 serum samples were analyzed for IgG and IgA against SARS-CoV-2 Spike (S) or nucleocapsid (N) proteins, in the pre- and post-vaccination periods. The latter included two doses of CoronaVac (group 1, G1), or ChAdOx-1 or BNT162b2 (group 2, G2), followed by heterologous booster doses. In the pre-vaccination phase, 26.5% of the participants showed IgG reactivity for S and 13.7% for N. After the vaccines' first dose, S IgG response was positive in 66.6% or 98% of G1 or G2 participants, respectively, whereas 100% of the participants showed S IgG positivity after the second dose, and S IgG and IgA after the booster. This initiative enabled the examination of viral transmission beyond hospital environments, which has rarely been explored, and established protocols for managing future emergencies. In addition, a serum bank and a comprehensive database are now available to the scientific community.

SARS-CoV-2 Genomic Surveillance in Brazil: A Systematic Review with Scientometric Analysis

Several studies have monitored the SARS-CoV-2 variants in Brazil throughout the pandemic. Here, we systematically reviewed and conducted a scientometric analysis of the SARS-CoV-2 genomic surveillance studies using Brazilian samples. A Pubmed database search on October 2022 returned 492 articles, of which 106 were included. Ninety-six different strains were reported, with variant of concern (VOC) gamma (n = 35,398), VOC delta (n = 15,780), and the variant of interest zeta (n = 1983) being the most common. The top three states with the most samples in the published articles were São Paulo, Rio de Janeiro, and Minas Gerais. Whereas the first year of the pandemic presented primary circulation of B.1.1.28 and B.1.1.33 variants, consecutive replacements were observed between them and VOI zeta, VOC gamma, VOC delta, and VOC omicron. VOI mu, VOI lambda, VOC alpha, and VOC beta were also detected but failed to reach significant circulation. Co-infection, re-infection, and vaccine breakthrough reports were found. Article co-citation differed from the co-authorship structure. Despite the limitations, we expect to give an overview of Brazil's genomic surveillance studies and contribute to future research execution.

Implemented occupational health surveillance limits the spread of SARS-CoV-2 Omicron at the workplace

The global spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has put an enormous pressure on human societies, at both health and economic levels. Early diagnosis of SARS-CoV-2, the causative agent of 2019 coronavirus disease (COVID-19), has proved an efficient method to rapidly isolate positive individuals and reduce transmission rates, thus alleviating its negative impact on society’s well-being and economic growth. In this work, through a coordinated and centralized effort to monitor SARS-CoV-2 circulation in companies from the State of Rio de Janeiro, Brazil, we have detected and linked an early rise of infection rates in January 2022 to the introduction of the Omicron variant of concern (VoC) (BA.1). Interestingly, when the Omicron genomic isolates were compared to correlates from public datasets, it was revealed that introduction events were multiple, with possible migration routes mapping to: Mali; Oman and United States; and Italy, Latin America, and United States. In addition, we have built a haplotype network with our genomic dataset and found no strong evidence of transmission chains, between and within companies. Considering Omicron’s particularly high transmissibility, and that most of our samples (>87%) arose from 3 out of 10 companies, these findings suggest that workers from such environments were exposed to SARS-CoV-2 outside their company boundaries. Thus, using a mixed strategy in which quick molecular diagnosis finds support in comprehensive genomic analysis, we have shown that a successfully implemented occupational health program should contribute to document emerging VoC and to limit the spread of SARS-CoV-2 at the workplace.

SARS-CoV-2 Molecular Epidemiology Can Be Enhanced by Occupational Health: The Experience of Monitoring Variants of Concern in Workplaces in Rio de Janeiro, Brazil

The emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to extra caution in workplaces to avoid the coronavirus disease 2019 (COVID-19). In the occupational environment, SARS-CoV-2 testing is a powerful approach in providing valuable information to detect, monitor, and mitigate the spread of the virus and preserve productivity. Here a centralized Occupational Health Center provided molecular diagnosis and genomic sequences for companies and industries in Rio de Janeiro, Brazil. From May to August 2021, around 20% of the SARS-CoV-2 positive nasopharyngeal swabs from routinely tested workers were sequenced and reproduced the replacement of Gamma with Delta variant observed in regular surveillance programs. Moreover, as a proof-of-concept on the sensibility of the occupational health genomic surveillance program described here, it was also found: i) the primo-identification of B.1.139 and A.2.5 viral genomes in Brazil and ii) an improved dating of Delta VoC evolution, by identifying earlier cases associated with AY-related genomes. We interpret that SARS-CoV-2 molecular testing of workers, independent of symptom presentation, provides an earlier opportunity to identify variants. Thus, considering the continuous monitoring of SARS-CoV-2 in workplaces, positive samples from occupation health programs should be regarded as essential to improve the knowledge on virus genetic diversity and VoC emergence.