The COVID-19 pandemic and the associated demand of mass testing have severely challenged worldwide supplies of commercial viral transport media as well as commercial swab kits and reagents for SARS-CoV-2 RT-PCR 5, 7. Minimal buffered systems, such as saline, have rarely been used for respiratory virus sample collection, transport, and storage in clinical practice in pre-pandemic times. As a more cost-efficient alternative to the commercially available product, the CDC provided a standard operating procedure for the production of viral transport medium suitable for viral detection based on Hanks Balanced Salt Solution, abbreviated as HBSS VTM in this study 7. In the present study, it was used as reference standard. The most commonly used commercial transport medium is the universal transport medium (UTM) from Copan Diagnostics which indeed has been proposed for use at room temperature for up to 48В h but not tested for higher temperatures and longer storage times 6.

Viral transport medium exists in several formulas, all consisting of a buffered salt solution, a complex source of protein and/or amino acids, and antimicrobial agents 5. The World Health Organization (WHO) recommends cooled storage (2вЂ“8В вЊ) and the transport of respiratory specimens in a specific viral transport medium (VTM) up to 5В days 4. Real-time PCR (RT-PCR), typically performed from upper respiratory specimens, represents the current gold standard for SARS-CoV-2 detection. Extensive laboratory testing for SARS-CoV-2 is currently among the most effective measures to curtail the spread of COVID-19, together with quarantine and social distancing measures 3, 4 as well as vaccination campaigns. The rapid spread of the novel coronavirus SARS-CoV-2, probably of zoonotic origin 1, has led to a continuing COVID-19 pandemic 2. Our study revealed the high resilience of SARS-CoV-2 and other respiratory viruses, enabling proper detection in clinical specimens even after long-time storage at high temperatures, independent of the transport mediumвЂ™s composition. Both alternatives to the commercial transport medium (UTM), HBSS VTM or saline, allow adequate detection of SARS-CoV-2 and other respiratory viruses, regardless of storage temperatures up to 28В вЊ and storage times up to 28В days.

We question the assumptions, that the choice of medium and temperature for storage and transport affect the accuracy of viral detection by RT-PCR. Therefore, our aim was to explore the reliability of minimal transport media, comprising saline or the CDC recommended Viral Transport Media (HBSS VTM), for the diagnosis of SARS-CoV-2 and other respiratory viruses (influenza A, respiratory syncytial virus, adenovirus, rhinovirus and human metapneumovirus) compared to commercial products, such as the Universal Transport Media (UTM). For reliable diagnosis of SARS-CoV-2 and other respiratory viruses, executed by Real-time PCR, the quality of respiratory specimens, predominantly determined by transport and storage conditions, is crucial. With global demand for SARS-CoV-2 testing ever rising, shortages in commercially available viral transport media pose a serious problem for laboratories and health care providers.

Bio rad cfx manager threshold