[Investigation of SARS-CoV-2-Specific Humoral and Cellular Immunity Values in Health Care Workers with COVID-19 Disease and Administered with COVID-19 Vaccine].

For limiting the coronavirus disease-2019 (COVID-19) pandemic, the effects on both humoral and cellular immune responses due to vaccines and previous infection should be taken into consideration. In some of the studies about the humoral immune response of the virus and different vaccines, it has been suggested that there can be a discordance between cellular and humoral immune responses during COVID-19 infection. The aim of this study was to determine the effects of humoral and cellular immune responses against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antigens in three groups of healthcare workers (HCWs) who were vaccinated with two doses of inactivated virus vaccine (CoronaVac), non-vaccinated and recovered COVID-19 infection and non-infected healthy controls by comparing the variables of gender and age and to examine the relationships between them.

Clinical Accuracy of Instrument-Read SARS-CoV-2 Antigen Rapid Diagnostic Tests (Ag-IRRDTs).

This systematic review (PROSPERO registration number: CRD42021282476) aims to collect and analyse current evidence on real-world performance based on clinical accuracy of instrument-read rapid antigen diagnostic tests (Ag-IRRDTs) for SARS-CoV-2 identification. We used PRISMA Checklist and searched databases (PubMed, Web of Science Core Collection and FIND) for publications evaluating the accuracy of SARS-CoV-2 Ag-IRRDTs as of 30 September 2021, and included 40 independent clinical studies resulting in 48 Ag-IRRDT datasets with 137,770 samples. Across all datasets, pooled Ag-IRRDT sensitivity was 67.

[The Second Shot of CoronaVac Vaccine May Cause Reduction of Antibody Levels in People who Previously had COVID-19].

The CoronaVac vaccine is an inactivated type two-dose regimen vaccine developed and manufactured by Sinovac Life Sciences Company, in China. It has already been used in China's vaccination program, while 21 other countries (including Indonesia, Turkey and Brazil) also granted emergency use authorization for this vaccine. In Turkey, on January 14, 2021, healthcare workers (HCWs) started to be vaccinated with CoronaVac as the priority group in vaccination.

[Evaluation of a Visually-Read Rapid Antigen Test Kit (SGA V-Chek) for Detection of SARS-CoV-2 Virus].

Although the reverse transcriptase polymerase chain reaction (RT-PCR) method has been accepted as the reference method in the detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA, it requires special laboratory conditions, complicated and expensive laboratory instruments, competent laboratory staff and long testing duration. Antigen testing methods such as enzyme immunoassay, fluorescent antibody and visually-read immunochromatographic rapid antigen detection (RAD) tests eliminated the above mentioned disadvantages of the RT-PCR. The aim of this study was to determine the performance of a RAD test kit (V-Chek, SGA Ltd, Ankara, Turkey).