Fig. 1

Viral load as a function of time from ICU admission in positive RT-PCR samples. Circles are individual RT-PCR measurements expressed as cycle threshold values (the lower the cycle threshold, the higher the viral load). Red and blue circles refer to patients alive and deceased at ICU discharge, respectively. Lines are regression lines for both groups, adjusted for the site of sampling (nasopharynx or lower respiratory tract) and RT-PCR technique. ICU intensive care unit, RT-PCR real-time reverse transcriptase polymerase chain reaction