ABSTRACT
We evaluated a novel transcription-reverse transcription concerted reaction (TRC) assay that can detect influenza A and B within 15 min using nasopharyngeal swab and gargle samples obtained from patients with influenza-like illness, between January and March 2018 and between January and March 2019. Based on the combined RT-PCR and sequencing results, in the nasal swabs, the sensitivity and specificity of TRC for detecting influenza were calculated as 1.000 and 1.000, respectively. In the gargle samples, the sensitivity and specificity of TRC were 0.946 and 1.000, respectively. The TRC assay showed comparable performance to RT-PCR in the detection of influenza viruses.
Subject(s)
Influenza A virus/isolation & purification , Influenza B virus/isolation & purification , Influenza, Human/diagnosis , Influenza, Human/virology , Nasopharynx/virology , Adult , Aged , Diagnostic Tests, Routine , Female , Humans , Male , Middle Aged , Prospective Studies , Sensitivity and SpecificityABSTRACT
OBJECTIVES: The accurate detection of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is essential for the diagnosis of coronavirus disease 2019 (COVID-19). We compared the quantitative RT-PCR results between nasopharyngeal swabs and saliva specimens. METHODS: A COVID-19 outbreak occurred on a cruise ship at Nagasaki port, Japan. We obtained 123 nasopharyngeal swabs and saliva each from asymptomatic or mild patients in the late phase of infection. RESULTS: The intervals from the diagnosis to the sampling were 25.5 days for nasopharyngeal swabs and 28.9 days for saliva. The positive rate was 19.5% (24/123) for nasopharyngeal swabs and 38.2% (47/123) for saliva (P = 0.48). The quantified viral copies (mean ± SEM copies/5 µl) were 9.3±2.6 in nasopharyngeal swabs and 920±850 in saliva (P = 0.0006). CONCLUSIONS: The advantages of saliva specimens include positive rate improvement and accurate viral load detection. Saliva may be used as a reliable sample for SARS-CoV-2 detection.
Subject(s)
COVID-19 Nucleic Acid Testing , COVID-19/diagnosis , Nasopharynx/virology , SARS-CoV-2/isolation & purification , Saliva/virology , Humans , Specimen HandlingABSTRACT
This retrospective study evaluated stored nasopharyngeal swab samples from Japanese patients with influenza-like illness during the 2019/2020 season. We aimed to determine whether COVID-19 had spread in the community before the first confirmed case. The period of influenza season during 2019/2020 in Nagasaki was shorter than in previous influenza seasons. When the first COVID-19 case was reported in Nagasaki prefecture, the number of influenza cases were very low. No positive results for SARS-CoV-2 were detected in 182 samples that were obtained from adult outpatients. Our results revealed no large-scale spread of COVID-19 in the community before the first confirmed case.