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Viral load dynamics and disease severity in patients infected with SARS-CoV-2 in Zhejiang province, China, January-March 2020: retrospective cohort study
…”Using a loess regression analysis, we found that in the mild group, the viral load in respiratory samples was greater during the initial stages of the disease, reached a peak in the second week from disease onset, and was followed by lower loads (fig 3). In the severe group, however, the viral load in respiratory samples continued to be high during the third and fourth weeks after disease onset (fig 3). The viral load of stool samples was highest during the third and fourth weeks after disease onset (fig 3).”
21 April
https://www.bmj.com/content/369/bmj.m1443
Study Raises Questions About False Negatives From Quick COVID-19 Test
The ID NOW has generated widespread excitement because it can produce results in less than 15 minutes.
...Abbott said any problems with the test could stem from samples being stored in a special solution known as viral transport media before being tested, instead of being inserted directly into the ID NOW testing machine. As a result, the company recently instructed all users to only test samples put directly into the machines.
Based on his study, Procop said his hospital has stopped using the test to screen patients being admitted for care. The hospital also stopped using another test, called the DiaSorin Simplexa, because it only detected 89.3% …
...the test developed by the Centers for Disease Control and Prevention, which detected 100% of positive samples. Another test, made by Roche, detected 96.5% of positive samples. The fifth test in the study, made by Cepheid, detected 98.2% of infected samples, Procop said. The Cepheid test produces results in less than an hour.
WLRN - Miami
https://www.wlrn.org/post/study-raises-questions-about-false-negatives-quick-covid-19-test