Dr. Gallant, my question is not technically a treatment question,

but nor is it an irritating "window period" or "am I infected" question.

I'm actually wondering if you can clarify a testing issue for me. I have seen

from some of the questions and answers on this forum a reference to the

results both of an ELISA and a Western Blot when discussing someone who has tested

hiv *negative*. Does this mean that in order to be considered negative

6 months or more after an exposure, one must test negative to both EIA and WB?

I had thought the usual procedure was a WB test only if the EIA was

repeatedly positive--that is,the specificity of the WB is used as a back-up to the

sometimes overly-sensitive and innacurate ELISA. Hence, my question: is a negative

ELISA without the WB sufficient to conclude the absence of infection, or must they

be used in tandem to determine one's hiv "negative" status at 6 months?

The Western blot is necessary to confirm a positive ELISA, but not necessary to confirm a negative ELISA. A negative ELISA at 6 months is adequate to rule out HIV infection.

JG