Scientists in a laboratory setting tested a new method to find SARS-CoV-2 virus particles. They used flow virometry along with temperature, detergent, antibodies, and dyes to examine virus samples. The team also looked at particle size, viral RNA levels, and infectivity. They studied supernatants from virus-infected cells and nasal swabs from patients confirmed to have the virus via PCR testing.
The researchers found virus particles measuring 70 to 100 nanometers in the infected cell samples. They noted that the appearance of these particles was associated with higher viral RNA levels and infectivity. When they treated samples with heat or detergent, the particles disappeared. The study also found that detecting the spike protein on the virus particles was a strong predictor of infectivity.
Importantly, the team detected SARS-CoV-2 particles directly in patient nasal swabs without needing to purify the samples first. This was done using standard lab techniques. Because this was a preclinical study performed in a laboratory, the results have not yet been tested in large groups of people. The study did not report any safety concerns because no human treatments were involved. Readers should understand that these findings are early and come from a small lab setting.
