Re: diseases and immunity

Mary Beth Williams (
10 Jul 1996 14:20:56 GMT

In <4rupkd$> (Gerold Firl)
>In article <4rufrh$>, Beth Williams) writes:
>|> In <4ru3hs$> (Gerold Firl)
>|> writes:
In article <4rufrh$>, Beth
Williams) writes:

|> HOWEVER, you're going to have to give a better citation than a
|> *MacNeil*, particularly when giving the level of detail regarding
|> symptoms of the infection. What were the bases for MacNeil's
|> assertions that this in fact was TB? Ethnohistoric accounts from
|> 19th century, or skeletal analysis by fizzies from the late 20th?

>I was wondering the same thing. He cites rene dubos, _man adapting_,
>as the source. Are you familiar with it? I've never heard of it

Gerold, you're taking a cite from a cite as hard evidence, and you're
not even sure of the primary data from which the interpretation
derives? Not very scientific, wouldn't you say?

|> As an aside, TB mortality rates among whites in the New World were
|> exceedingly high (I personally did a study of a nineteenth-century
|> white community in Connecticut where 15-20% of natural deaths were
|> attributed to *consumption*, i.e., TB), and thus Europeans never did
|> appear to develop an immunity to the disease.

>Immunity is a relative thing. If it takes 10 years for TB to kill you,
>then you are relatively immune, compared to someone who dies within a

>I would expect that a virgin-soil TB epidemic probably wouldn't leave
>any bone lesions, if people were killed-off fairly quickly. Which
>again leads to the question of how the TB diagnosis was made, and to
>which I still don't know the answer.

However, Indian populations in the 17th century do fulfill your
definition of having an immunity to TB, as there have been a number of
sites, including ones on which I have personally shared in the fizzy
work, where skeletal lesions associated with TB are present among a
significant portion of the mortuary population.

|> > It's very
|> >similar to what happened in europe when syphilis first appeared:
|> >individuals who were unfortunate enough to have no immunological
|> >response to the syphilis spirochete would die a few days after
|> >infected. They were eaten alive by the spirochete. Nasty, but
|> >the way it works.]

|> Do you have a citation for this? As syphilis would have first
|> in 15th-century Europe, I'm not sure I trust post-Medieval Europe's
|> understanding of pathologies the way you do. And, once again, if
|> died off right away, there would be nothing on the skeletal *record*
|> show evidence of such a demise.

>I'll try and find some cites for you on this; I think it was braudel,
>but I'll check.

>The european hypothesis that syphilis was a new world import dates
>back to 1539; the manifestations were so spectacular, and the pattern
>of propagation was so consistant (seville in the early 1490's,
>spreading to italy and then throughout europe) that the crude
>epidemiology of post-medieval europe was sufficient to make the

>The american hypothesis stood unchallanged until it was discovered
>that the spirochete responsible for yaws is indistinguishable from the
>syphilis pathogen. Yaws has been around in the old world forever. This
>has thrown the american-origin hypothesis into doubt, though I still
>find the coincidental timing to be compelling.

The most plausible present-day hypothesis is that Old World *yaws* and
New World endemic syphillis interacted and formed a new more lethal
strain of the organism. Hence, we have an example of where the
pathogen, not the host, mutated (which is not at all uncommon --
happens every year with the *flu*.)

Firl previously wrote:
|> >You can't see the trees for the forest, mb. Smallpox was the mosd
|> >important killer, but if smallpox hadn't existed, then another
|> >disease would have taken its place. If TB got to an isolated
|> >population before smallpox did, then TB would would kill them off.
|> >No one is using TB to explain the american die-off; the example was
|> >cited to illustrate the vulnurability of previously-unexposed |>
>populations to new pathogens.

|> TB never would have taken the place of small-pox or any other
|> childhood infection, as infection rates have never reached those of
|>these other diseases, in Indian or European populations. (In fact,
|>it has been strongly hypothesised that TB was present in
|> pre-Columbian populations in the Upper Midwest.)

>TB is an ancient organism, and may have been around in the pre-contact
>americas, but there are different strains of the bacillus, some more
>virulent than others. In resistant populations, TB is endemic, but in
>non-resistant groups there are different rules of the game. There, TB
>can act as an epidemic disease, and virulent strains suddenly become
>(temporarily) more viable.

The problem here is, Gerold, that you have no evidence, and in fact
there is _negative_ evidence, to support your claims that TB was an
*epidemic* versus *endemic* disease in either Indian or non-Indian
populations during the Contact Period. So far, you haven't produced
any primary documentation that would support such claims, and there is
ample physical evidence to show that skeletal TB, which you allege to
show *immunity*, is present in Contact, in most likely, pre-Contact
populations. Furthermore, one cannot distinguish pre-Contact from
post-Contact TB, and if there are, as you claim, different *strains*,
they do not manifest themselves within the human skeleton differently.

|> You example is an extremely poor one, Gerold,
|> as there appears to be some parity between Indians and non-Indians
|> when it comes to mortality rates from TB.

>If mcneill's example is correct, then what you say is not so. By the
>third generation, the mortality rates may be similar, but by then the
>damage has been done.

Sit back and think about this one carefully, Gerold. Are you claiming
that *epidemic* TB behaves like other epidemic diseases, such as
smallpox and measles, where the victim contracts the disease and either
dies rapidly, or survives, thus gaining an immunity? Because this is
the _only_ way that your purported *immunity* could be passed from
generation to generation, as the dead do not reproduce, and it is
impossible to pass on immunity _before_ the immunity has been
developed. Its a pretty little hypothesis, but unfortunately, you've
produced no evidence whatsoever to prove that there were droves of
Indians dying from TB contracted through their first contacts with
Euros. What the evidence _does_ show is that Indians and whites both
developed skeletal, and probably non-skeletal, TB from the time of
early Contact (and possibly before), with no discernible differences in
rates or mortality.

MB Williams
Dept. of Anthro., UMass-Amherst