A reliable source says the rabies test involves a brain tissue sample
under microscope, which causes death of host, assuming host is still alive.
His/her assertion makes sense, since great effort is made to locate the
biter quickly.  The Texan that showed positive must have died from the
disease, with the test result coming postmortem.  BIG's right, they don't
test live humans; by the time the virus shows itself in other tissues it is
incurable.
  The source further says that the virus travels along a nerve; the farther
the bite from the brain, the longer it takes for symptoms to manifest, and
the longer the bitee can wait.  At some point though, the disease reaches the
incurable stage.  If the bite is on the head, then the so-called "pastuer
treatment" must commence on the bitee immediately.
[Posted in FML issue 1168]