From: email@example.com(Steven B. Harris)
Subject: Re: Another Anitbiotic Mess-- drug resistant TB
Date: Thu, 30 Oct 1997
In <firstname.lastname@example.org> email@example.com
(hillary gorman) writes:
>On 24 Oct 1997 08:02:12 GMT,<firstname.lastname@example.org> wrote:
>* The problem in the US is that most docs here have never heard of
>*BCG, dispite that fact that we have a vaccine approved by the FDA for
>Really? Heck, they just spent an hour talking about that to us in my
>second year veterinary microbiology class! And they don't teach anything
>about BCG to medical doctoral students? Weird.
BCG is used in American medicine almost entirely by *urologists*,
who use it to treat superficial bladder cancer by instillation (the
infection in the bladder wall stimulates the body to wipe out the
cancer-- neat, huh?).
If you want to use BCG to vaccinate against TB in the US, and want
to use a US product, you have to get the Organon TICE stuff they sell
to urologists, and adapt it. Talk about feeling like you're doing
something not quite right.... I recently had to correct a bona-fide
professor of infectious disease about there being no FDA approved TB
vaccine in the US. NOBODY knows about this stuff.
The reason BCG hasn't cought on in the US is that long ago we
decided to forgo TB vaccination, so that infection could be more easily
diagnosed (the vaccine, though only 50% effective, makes all
immunologic TB tests worthless). That was a pretty good bargain so
long as TB was easily treated. As it become more resistant to drugs,
however, primary prevention will logically become more important, even
at the cost of diagnosis. Unfortunately, NOW we have to deal with the
inertia generated by the fact that "we've always done it another way."
People are going to want to know why we now want to use this stuff
which has always been around.
Steve Harris, M.D.
Who vaccinated myself with BCG in 1991
From: email@example.com (Steve Harris sbharris@ROMAN9.netcom.com)
Subject: Re: Tb Test and BCG
Date: 24 Nov 2004 15:54:03 -0800
hChen0906@gmail.com (Sharon) wrote in message
> I got my tb test last year, it was negative, I tested it again this
> year, the result is positive(borderline, adoptable), I checked my
> medical record, I got BCG vacinne when I came out of country 8 years
> ago, I am wondering if I have a inactive TB in my body or it is
> because I have BCG vaccine that my result is positive. Do I need to
> talk to my doctor about this?
> Thanks for your help.
Though BCG can cause a false positive in the PPD TB test, generally
the test is done anyway, unless the BCG is very recent (1 year), since
it usually takes a very recent BCG to give the clear false positive.
In your case, it's been so long it's almost certainly not going to
happen. The most severe reactions on the PPD (10 mm and certainly more
than 15 mm) are generally considered to be due to TB and never BCG.
The real interpretive problems are in people with BCG from a year or
so ago with intermediate reactions of 5 mm to 10 mm. Those are people
who in the past had to get X-rayed and re-tested, and sometimes even
treated with INH presumptively.
Fortunately, there's recently been approved now a nice blood test for
latent TB, which has controls for M. Avium and for BCG, so you can
answer this question for certain if you have a skin test in the
intermediate zone, and the question of BCG false positives becomes a
problem. It's called QuantiFERON. Check out.
I hope with the availability of the new blood test, we can at last now
start considering mass BGC vaccination in the US (which other than
Holland is the only Western country without a population vaccination
program for TB). Mostly it's the problem of false positives and
inertia which has held it up in the US. BCG is not a perfect vaccine,
and there's even some question if it prevents much pulmonary TB.
However, it does do some good, and the good is mounting as TB becomes
nastier. BCG does appear to decrease the multi-organ dissemination of
TB, and because it's an immune treatment, there's no doubt as
protective against dissemination from multi-drug resistant TB as any
other kind of TB. So if you ever get 5-drug or 6-drug resistant strain
of TB, you're gunna wish you had had it. That stuff spreading in your
bone marrow and lymph nodes might as well be AIDS. Or worse, because
we have a number of drugs that can slow down or hold most cases of
I've had my BGC, which I obtained from Organon about 10 years ago and
did myself, somewhat clumsily (it works much better if you use an
insulin needle to poke yourself very shallowly through the vaccine
pool many times, rather than the silly magnet-and-tine-block set-up
you get from Organon, if that's what they still ship). I had to do my
own, because if you ask most US doctors about this, they won't know
what the devil you're talking about and will probably never have done
a TB vaccination. You can, however, get the TICE BCG even here in the
US, since it's approved for health care workers, but frowned upon and
not talked about, almost like it was a social stigma. My forearm had a
nasty sore for a month. But I have no scar now. Probably my immune
system will have some memory left if I should come across the real
bug. Just because your skin test goes back to "normal" doesn't
necessarily mean all your lymphocytes have forgotten everything. I'm
convinced that traces of immunity are left from every vaccine and
infection you ever had.
From: David Rind <firstname.lastname@example.org>
Subject: Re: Tb Test and BCG
Date: Wed, 24 Nov 2004 21:55:13 -0500
> Hi David:
> Thanks for your replies. I am not a medical professional, but I do
> think what the nurse said make sense, from the all the related web
> articles, I think, if one has a BCG test long time ago, the effection
> will be reduced along the years, I was in the borderline(10mm) for
> this time while BCG has little effect, next year, the BCG effect will
> be reduced more, so at that time, it will make more sense to tell
> whether one has an inactive TB or because of BCG. I know American
> keep telling that BCG has no function to against TB, and BCG should
> not count to the TB result reading, but if I have inactive TB, where I
> got it, in the US? I came out of my country 8 years ago, I've never in
> close contact with any active TB patient through out my life.
> Thanks, of course, I will go to my doctor soon.
Just to reiterate: there's no reason to expect the PPD result to turn
negative if it is rechecked next year. If the assumption is that the
entire reaction was due to BCG, and that it went from negative in the
past to positive now because it was "boosted" by a PPD test one year
ago, it will likely have been booster still more by the PPD test this
year. As a result, the reaction next year would be expected to be at
least as large as the reaction this year and won't help distinguish
latent TB from a BCG reaction.
I'm not arguing that you should necessarily blindly follow the US
recommendation to ignore the BCG in interpreting a PPD result. Rather
that this is complex and really worth talking to someone knowledgeable
about. Issues like whether you might have been exposed (for instance
whether you have friends and relatives who are also immigrants from
somewhere where TB is prevalent) are part of what goes into thinking