Three types of antibodies are created in response to infection, i.e., immunoglobulin A (IgA), IgG and IgM, which rise or fall at different times after the onset of infection.197–201 IgG is used in most antibody tests given that it persists for the longest time and may reflect longer-term immunity, while IgM typically rises quickly with infection and declines soon after infection is cleared. Here, CD40LG is linked to infection.