Anthrax and antibiotics: Is evolution relevant?
by Dr Jonathan Sarfati
15 November 2001; updated 8 April 2005
After the terrorist attack
on 11 September, many people fear a new danger—biological warfare
in the form of anthrax. Perhaps understandably, many Americans are taking
antibiotics such as Cipro (ciprofloxacin) as a preventative measure. Data from the
pharmaceutical tracking company NDCHealth of Atlanta, Georgia, show that almost
63,000 more Cipro prescriptions have been issued in the third week of October alone
than for the entire previous year. However, this has caused some concern in the
medical profession that antibiotic overuse could result in antibiotic resistance
in many types of bacteria. Not surprisingly, the humanist-dominated secular media
has used phrases such as ‘Bacteria evolve drug resistance very quickly’.
Fortunately, in the current round of articles, I haven’t seen repeated the
hysterical outburst of one particular evolutionary propagandist who claimed that
people will die because of creationists, because they will allegedly fail to understand
this vital fact of evolution of drug resistance.
We have covered antibiotic resistance in many articles on this website. So here
it will suffice to summarize the main issues to enable people to assess critically
any articles on this current scare. First some principles:
To apply these principles to antibiotic resistance, there are several ways that
germs can acquire resistance to drugs, none of which have anything to do with evolution
from goo to you via the zoo:
- Natural selection: the drugs wipe out all the non-resistant germs,
so the most resistant germs survive and multiply. This leads to a whole population
that’s resistant to antibiotics. This is not evolution because
the resistance already existed in the population. Despite this, the
PBS Evolution propaganda series used selection of pre-existing
antibiotic resistance in tuberculosis germs as a major ‘proof’.
In fact, some bacteria revived from corpses frozen before the development of antibiotics
have shown resistance.
Selection for resistant bacteria is a real danger when a patient fails to complete
a prescribed course of antibiotics (60 days for Cipro)—i.e. stops taking the
drug when the symptoms ease, which just means that most germs have been
destroyed. The remnants require the final doses of antibiotic to finish them off,
but if the treatment stops, they are free to multiply. This time the drug is far
less effective, since the remnant population will tend to be the more resistant
ones.
This problem of selection of resistant varieties applies not only to the targeted
germ, but all the other types affected by the same antibiotic. This is the main
reason that the medical profession is concerned with people taking Cipro for a few
days because of the anthrax scare. Indeed the over-use of Cipro could result in
many germs that are resistant to this drug, so the concern is very well founded.
Antibiotics as a preventative measure are warranted only where there’s evidence
that people were in a ‘breathing zone’ of the deadly airborne anthrax
spores, not for the milder skin form of anthrax.
- Sometimes bacteria can pass on information to other bacteria, via
loops of DNA called plasmids. Sometimes plasmids contain information for
antibiotic resistance. But here too, the information already existed, so
this is not evolution.
Information-losing mutations can confer resistance. Such mutations
are often harmful in an ‘ordinary’ environment without antibiotics.
It is well documented that many ‘superbugs’ are really ‘superwimps’
for this reason—see Superbugs not super after all
. Also, some sorts of information-losing mutations evidently cause
HIV resistance to antivirals, because the ‘wild’ types easily
out-compete the resistant types when the drugs are removed. Despite this, this was
promoted as another ‘proof’ of evolution by the PBS series.
So, how can an information loss confer resistance? Here are some observed
mechanisms:
- A pump in the cell wall takes in the antibiotic. A mutation
disabling this pump will prevent the bacterium pumping in its own executioner.
But in the wild, a bacterium with a disabled pump will be less fit than other bacteria
because the pump also brings nutrients, etc., into the cell.
- A control gene regulates the production of an enzyme that destroys the
antibiotic, e.g. penicillinase which destroys penicillin. A mutation disabling
this gene destroys the regulation of the production, so far more enzyme is produced.
Such a bacterium can cope with more antibiotic than others can, but in the wild,
it would be less fit than normal because it’s wasting valuable resources producing
more enzyme than is needed.
- An enzyme is highly specialized to break down one specific type of chemical
very well, and hardly affect other chemicals. A mutation could reduce its specificity,
i.e. it no longer does its main job so well, and affects other chemicals to some
extent too. Normally, a biological system with such a mutation would not function
as well, and reduced specificity is reduced information by definition.
But sometimes the other chemicals affected happen to be antibiotics, so this type
of mutation confers resistance. See further discussion in this
refutation of a critic and Not By Chance (top right), ch. 5.
- The antibiotic streptomycin works by attaching onto a precisely matching site
on the surface of a bacterium’s ribosome, where decoding of DNA information
to proteins occurs. When the streptomycin attaches, it stops this machinery from
producing the right proteins, and the bacterium dies. Resistance to the drug can
be caused by an information-losing mutation that degrades the surface of a bacterium’s
ribosome, which reduces the binding ability of the drug to the ribosome,
preventing it from ruining the protein manufacturing machinery.
- More detail on information-losing resistance-increasing mutations can be found in
the article
Is bacterial resistance to antibiotics an appropriate example of evolutionary change?
These principles should be enough to demonstrate that these latest claims about
bacteria ‘evolving’ resistance are not a threat to Biblical creation.
Despite all this, many evolutionist crow about antibiotic resistance as an amazing
‘prediction’ of evolution. Even aside from the above points, this is
revisionist history. Historically, antibiotic resistance first took the medical
profession by surprise—even as late as 1969, experts stated that ‘infectious
diseases were a thing of the past’. I.e. antibiotic resistance was hardly
a ‘prediction’ of evolution, but is really a phenomenon explained ‘after
the fact’ by evolutionary language. But as shown, the Biblical Creation/Fall
model explains it better.
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