Figure 2. Protocol-Specific Individual-Level SARS-CoV-2 Viral Load Data Over Illness Visits.

Blue dots denote individual viral load values based on nasal and/or nasopharyngeal (NP) swabs; gray lines connect results from the same participant. Orange curves are smooth estimates using locally estimated scatterplot smoothing and summarize viral load trends based on nasal and/or NP swabs. Moderna collected saliva swabs post–COVID-19 onset, which are not shown given the focus on viral load based on nasal/NP swabs.

^aCOVID-19 onset was defined in each parent protocol: the date of first positive polymerase chain reaction (PCR) test (AstraZeneca), symptom onset (Janssen), the earlier of the 2 (Novavax), or the later of the 2 (Moderna). Thus, for Janssen and Moderna some PCR-positive tests prior to COVID-19 onset were observed.