All the seronegative subjects had a PCR cycle threshold >= 29, with the vast majority above 35, indicating relatively low virus levels. Figure 1, B: https://ww

All the seronegative subjects had a PCR cycle threshold >= 29, with the vast majority above 35, indicating relatively low virus levels. Figure 1, B: https://wwwnc.cdc.gov/eid/article/27/9/21-1042-f1 https://wwwnc.cdc.gov/eid/article/27/9/21-1042-f1