Figure 3.

Severity of adverse reactions (compared with those post first and second doses).

Box plots of anti-spike IgG titers after second vaccination showing themedian, quartiles, and outliers. The following four groups were included: “None,”“1^st,” “2^nd,” and “Same” representing participants whohad no reactions after either dose, stronger reactions after 1^stdose, stronger reactions after 2^nd dose, and same level of reactionsafter the 1^st and 2^nd doses, respectively. IgG levels in participantswho had stronger reactions after 2^nd dose were higher than levels inparticipants who had same level of reactions after the 1^st and 2^nddoses (***P < .001).