CD40LG and infection: Although genomic sequencing is mandatory to confirm a re-infection case7, evidence such as a long asymptomatic period (39-192 days), a long interval between positive RT-PCR results (62-195 days), undetectable IgM and IgG antibodies after the first infection, and a prompt increase in IgM and IgG during the second symptomatic period are highly suggestive of re-infection.