CD40LG and infection: We also assessed the performance of the IBMP Spike IgA/IgM/IgG ELISA in different infection periods, classifying samples based on symptom onset as follows: 0–7 days post symptom onset (n = 20; Median: 4 days; IQR: 2.25–5 days), 8–14 days post symptom onset (n = 21; Median: 10 days; IQR: 9–13 days), and 15–21 days post symptom onset (n = 23; Median: 18 days; IQR: 16–21 days).