Depending on the virus, it can take weeks for antibodies
to develop after exposure to the virus. In these situations, test results may
be negative early in the course of the infection. This is called a
false-negative test result. Another blood sample may
need to be drawn later to check again for a viral infection. Antibody titers
that get higher over 3 weeks from the first sample to the second mean the
infection occurred recently.
Normal (results that do not show a viral infection are
No antibodies to the virus are
Viral antigen detection
No antigens made by the viral
infection are found.