When penicillin was discovered in 1945, doctors hailed it as the
miracle drug that would finally put humans ahead in the battle
against bacterial infections like syphilis and cholera.
U.S. Surgeon General William Stewart declared in 1969 that with
the power of antibiotics, humans would never again be bothered by
the microscopic bugs.
Victory, however, was short-lived. And the slow and steady
defeat has yet to be widely recognized.
Over-prescription of antibiotics is now causing problems that
are more serious than those they once solved.
The two million pounds of antibiotics produced in 1954 has
increased to 50 million pounds today. But no matter how many drugs
are manufactured, the bacteria will always stay one evolutionary
step ahead.
A population of bacteria can double in number in 20 minutes.
This rapid reproduction rate allows for a high frequency of
mutations. By chance, some of these mutants will have the ability
to withstand antibiotics.
“We’re losing the war against bacteria,” said
Jeffrey H. Miller, UCLA professor of microbiology, immunology, and
molecular genetics.
“The bugs are winning and we can’t develop new drugs
fast enough to counteract their ability to develop resistance to
these drugs.”
The first strain of bacteria to put up a fight against
penicillin was Staphylococcus aureus ““ a microbe that
naturally resides in the human body ““ but can cause
infections that lead to pneumonia or toxic shock syndrome.
Antibiotics work by inhibiting bacteria’s ability to
multiply. Penicillin, for example, attaches to specific enzymes and
prevents the formation of the bacterial cell wall.
Strains of S. aureus became resistant to penicillin with a
simple alteration of the proteins to which the drug binds.
Although bacteria are programmed to rapidly evolve and mutate
against drugs, modern human habits are also giving them a helping
hand.
“Human activities continue to evolve and those activities
put us in contact with microorganisms,” said Claire Panosian,
a clinical professor in the division of infectious diseases of the
UCLA Medical Center and director of the Travel and Tropical
Medicine Clinic.
“We accept these modern changes very happily but they put
us at greater risk for infection.”
Several decades of doctors’ unnecessary prescription of
antibiotic and patients’ erroneous dependence have also
contributed to the resistance-phenomenon doctors face today.
“Viral infections like the common cold or the flu
aren’t going to be helped by antibiotics at all, but tons of
people chomp down on them,” Miller said.
“Doctors have given up because patients think that they
aren’t being helped if they’re not getting
antibiotics,” he added.
The human body serves as bacteria’s ideal ecological
niche. Most of these bacteria are harmless guests who serve the
important purpose of taking up space and preventing the settlement
of less friendly invaders.
A course of antibiotics will not only kill illness-causing
germs, but also these good bacteria. The microbes left after the
medication are those that have developed resistance.
According to the Center for Disease Control and Prevention, a
third of the 150 million outpatient prescriptions for antibiotics
written annually are unnecessary ““ the infection either turns
out to be viral or the wrong drug is prescribed.
Humans, however, are not the only ones who consume antibiotics
in excess.
Forty percent of the antibiotics manufactured, the CDC reports,
are fed to livestock under the premise that it makes them grow
faster and fatter.
Resistant bacteria from the cows, pigs, and chickens can be
transmitted to humans who handle the animals or eat uncooked
meat.
Aside from antibiotic resistance, the emergence and spread of
new infectious diseases like severe acute respiratory syndrome are
also aided by planes, trains and automobiles.
“People who were living in jungles might get an infection,
but they wouldn’t travel anywhere and the outbreak would die
out very quickly,” said Scott Filler, professor of medicine
at the UCLA David Geffen School of Medicine and researcher in the
division of infectious diseases at the Harbor-UCLA Medical
Center.
“But with worldwide travel, people in jungles can now
infect other people,” Filler said.
The rate of emerging infections is also rising with an increased
population of patients with a weakened immune system.
“We have more and more patients who are immunocompromised
because of AIDS or chemotherapy and they develop infections that
other people just don’t get,” Filler said.
Many of the infections are developed within hospitals and
intensive care units, consistent hot spots for antibiotic use. The
resulting “super germs” can then be spread by doctors
and nurses.
In light of the unrelenting rate of microbe resistance, the CDC,
the Food and Drug Administration, and the National Institutes of
Health joined in 1999 to co-chair the Federal Interagency Task
Force on Antimicrobial Resistance to educate patients and doctors
on correct antibiotic use and to develop more effective public
health measures.
“As long as we have antibiotics, we will have new bugs
that develop resistance to antibiotics,” Panosian said.
“The good news is that most of us survive very well, and
we live longer and healthier than any other generation. This is
something that we should be informed of and stay one step ahead of
if we can.”