Figure 6.

SARS-CoV-2 viral loads in oropharyngeal swabs and respiratory tissues and detection of neutralizing antibodies. (a) Total viral RNA (left panels), sgRNA (middle panels) and virus titers (right panels) in oropharyngeal swabs, trachea, nasal turbinates (conchae) and lung, measured in N = 2 hamsters per age group on days post-infection (DPI) 0–10, and N = 8 on DPI 21. RNA quantities were determined by RT-qPCR and are expressed as log10 RNA copies per swab or per gram of tissue. Virus titers were determined by virus isolation. Samples displayed with a value of “1” had undetectable virus or viral RNA content. (b) Neutralizing antibody titers as determined by virus neutralization tests and expressed as 50% neutralization titer (MN₅₀). Samples displayed with a value of “1” had undetectable antibody titer. (a,b) Each symbol represents a value of an individual animal and lines show averages. Horizontal dotted line shows the detection limit of the test. For statistical analysis, linear regression model was used to compare differences in the viral load dynamics between adult and juvenile hamsters in time. The adjusted R-squared value for the regression models is shown in the respective graphs. Differences with p values ≤ 0.05 were considered significant. Significance code: *—p ≤ 0.05; ***—p ≤ 0.001; ns—not significant; ND—not done.