Fig. 3: NAb reactivity in convalescent COVID-19 and control sera with non-COVID-19 infection by the SONIA neutralization PCR test.

Convalescent COVID-19 sera (N = 144) were from patients 14 days after symptom onset (blue circle), and control sera (N = 43) from patients with HCV, flavivirus infection and Lyme disease (pink square). The y-axis is the SONIA neutralization PCR test signal Δ\(\overline{{Ct}}\) calculated by subtracting the Ct value of the sample from that of a buffer only blank control.