Figure 2:

Once the patient gets infected with SARSCoV-2, viral replication in susceptible cells of the respiratory track increases and may remain active until 28 days of infections in symptomatic or asymptomatic patient (red line). One-week post infection IgM begins to be produced in response to the virus and remain for 2–3 weeks (blue line). After IgM declines, IgG begins to be produced and remain positive thereafter (green line).