The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is pressing public health systems around the world, and large population testing is a key step to control this pandemic disease. Here, we develop a high-throughput targeted proteomics assay to detect SARS-CoV-2 nucleoprotein peptides directly from nasopharyngeal and oropharyngeal swabs. A modified magnetic particle-based proteomics approach implemented on a robotic liquid handler enables fully automated preparation of 96 samples within 4 hours. A TFC-MS system allows multiplexed analysis of 4 samples within 10 min, enabling the processing of more than 500 samples per day. We validate this method qualitatively (Tier 3) and quantitatively (Tier 1) using 985 specimens previously analyzed by real-time RT-PCR, and detect up to 84% of the positive cases with up to 97% specificity. The presented strategy has high sample stability and should be considered as an option for SARS-CoV-2 testing in large populations.

The current outbreak of severe acute respiratory syndrome associated with coronavirus 2 (SARS-CoV-2) is pressing public health systems around the world, and large population testing is a key step to control this pandemic disease. Real-time reverse-transcription PCR (real-time RT-PCR) is the gold standard test for virus detection but the soaring demand for this test resulted in shortage of reagents and instruments, severely limiting its applicability to large-scale screening. To be used either as an alternative, or as a complement, to real-time RT-PCR testing, we developed a high-throughput targeted proteomics assay to detect SARS-CoV-2 proteins directly from clinical respiratory tract samples. Sample preparation was fully automated by using a modified magnetic particle-based proteomics approach implemented on a robotic liquid handler, enabling a fast processing of samples. The use of turbulent flow chromatography included four times multiplexed on-line sample cleanup and UPLC separation. MS/MS detection of three peptides from SARS-CoV-2 nucleoprotein and a 15N-labeled internal global standard was achieved within 2.5 min, enabling the analysis of more than 500 samples per day. The method was validated using 562 specimens previously analyzed by real-time RT-PCR and was able to detect over 83% of positive cases. No interference was found with samples from common respiratory viruses, including other coronaviruses (NL63, OC43, HKU1, and 229E). The strategy here presented has high sample stability and low cost and should be considered as an option to large population testing.

SUMMARYVirus-Associated Hemophagocytic Syndrome (VAHS) is a severe hematological disorder related to some viral infections. It is an illness characterized by persistent fever, pancytopenia, splenomegaly, hyperferritinemia and, the most important, hemophagocytosis observed in the bone marrow, liver and/or lymph nodes. VAHS associated with hepatitis A virus infection is rarely described, despite the high incidence of this viral infection in the population in general. There is no consensus in the literature regarding the optimal treatment of VAHS. In this article the clinical features, presumed pathogenesis, diagnostic criteria and treatment of VAHS are discussed, including description of cases of VAHS related to hepatitis A virus infection found in the medical literature.

We evaluated the seroprevalence of SARS-CoV-2 and risk factors among 4,987 oligo/asymptomatic HCW. The seroprevalence was 14% and factors associated with being infected with SARS-CoV-2 were lower educational level(aOR of 1.93;95%CI1.03-3.60), using public transport to work (aOR of 1.65;95%CI 1.07-2.62), and working in cleaning or security (aOR of 10.1;95%CI 3.40-26.9).

HDV infection is infrequent in the Southeast Region of Brazil, however there have been a few cases in this region. HIV/HBV patients are at potential risk for HDV infection, therefore investigations for the presence of HDV infection must be carried out in these patients.

The current outbreak of severe acute respiratory syndrome associated with coronavirus 2 (SARS-CoV-2) is pressing public health systems around the world, and large population testing is a key step to control this pandemic disease. Real-time reverse-transcription PCR (real-time RT-PCR) is the gold standard test for virus detection but the soaring demand for this test resulted in shortage of reagents and instruments, severely limiting its applicability to large-scale screening. To be used either as an alternative, or as a complement, to real-time RT-PCR testing, we developed a high-throughput targeted proteomics assay to detect SARS-CoV-2 proteins directly from clinical respiratory tract samples. Sample preparation was fully automated by using a modified magnetic particle-based proteomics approach implemented on a robotic liquid handler, enabling a fast processing of samples. The use of turbulent flow chromatography included four times multiplexed on-line sample cleanup and UPLC separation. MS/MS detection of three peptides from SARS-CoV-2 nucleoprotein and a 15N-labeled internal global standard was achieved within 2.5 min, enabling the analysis of more than 500 samples per day. The method was validated using 562 specimens previously analyzed by real-time RT-PCR and was able to detect over 83% of positive cases. No interference was found with samples from common respiratory viruses, including other coronaviruses (NL63, OC43, HKU1, and 229E). The strategy here presented has high sample stability and low cost and should be considered as an option to large population testing.

In recent years the immunomodulatory actions of vitamin D, a steroid hormone, have been extensively studied. In 2020, due to the COVID-19 pandemic, the question arose as to 25(OH)D status would be related to susceptibility to SARS-CoV-2 infection, since several studies pointed out a higher prevalence and severity of the disease in populations with low levels of 25(OH)D. Thus, we investigated the 25(OH)D levels in adults "Detected" positive for SARS CoV-2 by RT-PCR (reverse transcriptase polymerase chain reaction) test, and in negative controls, "not Detected" , using the Fleury Group's examination database, in Sao Paulo, Brazil. Of a total of 14.692 people with recent assessments of 25(OH)D and RT-PCR tests for COVID-19, 2.345 were positive and 11.585 were negative for the infection. The groups did not differ in the percentage of men and women, or in the age distribution. There were no differences in the distribution of 25(OH)D between the two groups (p = 0.08); mean 25(OH)D of 28.8 ± 21.4 ng/mL and 29.6 ± 18.1 ng/mL, respectively. In the specific population studied, clinical, environmental, socioeconomic and cultural factors should have greater relevance than 25(OH)D in determining the susceptibility to COVID-19.

No abstract