RESUMO
Saliva sample can be self-collected and used in testing of SARS-CoV-2 nucleic acid amplification tests (NAATs) test in Japan. However, this may have difficulty collecting a proper specimen when collecting for the first time. We compared 2 collection methods, conventional methods and Direct Saliva Sample Collection method (DiSC) from 44 asymptomatic or symptomatic individuals who were in quarantine in Toho university hospital. RT-PCR by DiSC method showed about 70 % positive percent agreement compared to RT-PCR by conventional methods. In addition, comparing RT-PCR and TMA by DiSC method, TMA showed about 90 % positive percent agreement compared to RT-PCR. DiSC method is easy to perform by every person, does not have complicated restrictions/instructions and can be used in RT-PCR and TMA. This method allows for ease of saliva collection in certain patient populations.
RESUMO
There is a worldwide attempt to develop prevention strategies against SARS-CoV-2 transmission. Here we examined the effectiveness of visible light-responsive photocatalyst RENECAT on the inactivation of SARS-CoV-2 under different temperatures and exposure durations. The viral activation on the photocatalyst-coated glass slides decreased from 5.93{mp}0.38 logTCID50/ml to 3.05{mp} 0.25 logTCID50/ml after exposure to visible light irradiation for 6h at 20 degree C. On the other hand, lighting without the photocatalyst, or the photocatalyst-coat without lighting retained viral stability. Immunoblotting and electron microscopic analyses showed the reduced amounts of spike protein on the viral surface after the photocatalyst treatment. Our data suggest a possible implication of the photocatalyst on the decontamination of the SARS-CoV-2 in indoor environments, thereby preventing indirect viral spread.
RESUMO
We evaluated the rapid immunochromatographic test for SARS-CoV-2 antigen detection using 16 saliva specimens collected from 6 COVID-19 hospitalized patients, and detected N-antigen in 4 of 7 RT-PCR positive specimens. The POCT antigen test using saliva is highly considered to be a game-changer for COVID-19 diagnosis.