German study on viral load kinetics and seroconversion timescale, out in @nature. Highlights huge time sensitivity of swab testing, viral loads in upper respiratory tract tank after ~5 days of symptoms (swabs are yellow line, orange is sputum).

Link to study, sorry: https://www.nature.com/articles/s41586-020-2196-x_reference.pdf

Seroconversion is also slow! Only 50% after 7 days. This is important for applications of commercially available rapid serology tests, e.g. for back to work programs.

Lots of interesting data here. Viral sequencing indicates distinct genotypes in throat and sputum, indicating active viral replication in throat. Importantly, this study does not observe severe cases. This is a strength IMO, most papers have studied blazing hot patients

By the time patients are tested (2-4 days post symptom onset), they are clearly well beyond their peak of viral load in nose/throat. Partially explains the high false negative rate of swabs (20-25%). This is why rapid/widespread testing and faster turnaround is critical.