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But before you plan your centennial years, consider this. That poultry you've
been consuming may be as much a health problem as that steak you gave
up. Not in the clogging-your-arteries way -- although if you're going to eat
your chicken fried with the skin on you might as well have a Philly cheese
steak.
No, poultry's potential poison is more insidious and, ultimately, more
threatening in the long term. The problem with poultry comes from the
antibiotics these birds are fed in their meal, drugs used primarily to make
them more productive rather than to cure sickness.
These drugs in turn can help make doctor-prescribed antibiotics less
effective -- and in the most dire cases, completely ineffective -- against
disease in the humans eating the chicken. Add to this a processing
procedure that critics say is a health hazard in and of itself, and you've got a
health crisis in the making.
Before we go further, a couple of caveats. As with all dietary discussions,
moderation and common sense are of the essence. If you eat a raw egg
every day, never wash your chicken before cooking it and use the same
knife to cut up your poultry and your vegetables, then it's your own damn
fault if you eventually get salmonella or campylobacter, the two most
common forms of food-borne illnesses from poultry.
"It's consumer education as much as the processor," says professor and
poultry specialist Michael Darre. "If you don't follow up at home, all that
good work beforehand is useless."
The caveat continues with the antibiotic angle. Scientists and researchers
everywhere agree that the major culprit in the increasing number of antibiotic
resistant bacteria -- super bugs if you will -- are doctors who prescribe an
antibiotic at the least sneeze. These people are closely followed by the
patients who come in and demand a drug for said sneeze, especially if the
sneeze, runny nose and sore throat belong to a child. All you working
parents out there know exactly who you are.
To make an increasingly bad situation worse, too many people don't finish
their prescriptions. They feel better a few days later and figure they'll save
the rest of their prescription to get a jump on the next illness.
The problem is that although the drug may have killed off 90 percent of the
bacteria, that remaining 10 percent becomes stronger and more resistant to
the drug, rendering it increasingly ineffective as this pattern continues.
These caveats aside, the health world is becoming progressively worried
about the increase in these antibiotic-resistant strains and turning to the
animal agricultural world to find part of the solution.
Currently 70 percent of all antibiotics produced go into our livestock.
Although other food animals such as cattle and pork are fed antibiotics for
reasons other than to cure an illness, neither group receives as much as
poultry. The Union of Concerned Scientists (UCS) a nonprofit partnership
of citizens and scientists working to preserve health, estimates in its January
2001 report, "Hogging It: Estimates of Antimicrobial Abuse in Livestock,"
that livestock producers in the United States use 24.6 million pounds of
antimicrobials for nontherapeutic use every year. Of this, about 3.5 million
pounds is given to cattle, 10.3 million pounds to hogs, and 10.5 million
pounds to poultry. That tonnage would be even higher if therapeutic use was
included.
And nonprofits like the UCS aren't the only ones paying attention.
Government agencies have also begun to tackle the problem, creating task
forces and programs to better monitor overall drug use. Concludes the
Centers for Disease Control and Prevention (CDC) after one study of
salmonella infections in humans, "There is an urgent need to emphasize
non-antimicrobial infection control strategies."
Driven primarily by increased use in poultry, overall use of antimicrobials for
nontherapeutic purposes has risen by about 50 percent since 1985,
according to the report. In poultry, nontherapeutic use since the 1980s has
increased by over 8 million pounds, a dramatic 307 percent increase on a
per-bird basis. (Growth in industry size accounted for about two-fifths of the
overall increase.) In contrast, humans receive 3 million pounds annually.
"For sheer overprescription, no doctor can touch the American farmer,"
notes a Newsweek article called "The End of Antibiotics." "Farm animals
receive 30 times more antibiotics (mostly penicillins and tetracyclines) than
people do. The drugs treat and prevent infections. But the main reasons
farmers like them is that they also make cows, hogs and chickens grow
faster from each pound of feed. Resistant strains emerge just as they do in
humans taking antibiotics -- and remain in the animal's flesh even after it
winds up in the meat case."
"We fully realize the human side is a good part of the picture," says Dr.
Deborah Huang, a science policy fellow at the Center for Science in the
Public Interest (CSPI), a nonprofit education and advocacy organization
that focuses on improving the safety and nutritional quality of our food
supply. "We feel there's enough science out there to support the conclusion
that antibiotic use in animals can contribute to resistance in humans."
That poultry has the potential to have a huge impact on our health is not
surprising given its increasing popularity in recent years. In 1960, eggs
accounted for 61 percent of gross chicken income in the U.S., with broilers
at 34 percent, according to Karen Davis of United Poultry Concerns, a
nonprofit educational group focusing on poultry. By 1975, broilers supplied
50 percent of the gross chicken income with eggs coming in at 49 percent.
Negative news about cholesterol and increasingly frenetic lifestyles helped
bring an end to the big breakfast in America and with it, a drop in egg
consumption. Between 1960 and 1990, egg consumption dropped from
about 321 to 235 eggs per person annually.
At the same time, chicken and turkey began to be regarded as an
inexpensive and convenient low-fat protein source. In 1993 U.S. hog
producers killed in one week 1.7 million pigs, an average of 10,000 pigs an
hour, that standing in single file, would stretch 1,200 miles from New York
City to Kansas City.
But in that same week U.S. broiler producers killed 135 million chickens, an
average of 800,000 chickens an hour, enough to stretch in single file 25,000
miles or completely around the middle of the earth.
That demand has driven the market to new lengths to fill consumer need.
Although chicken farms existed for centuries, the industry itself is still
relatively young. Before the 1920s, most chicken farms were
second-income operations on the family farm. The focus was on the eggs,
with the meat just a by-product once a hen's laying days were over. The first
year-round broiler production operation began in 1926 when Cecile Long
Steele and her husband built a year-round farm capable of producing
10,000 chickens. Today, that would be considered small.
It would also be considered economically inadequate. In the early days of
the industry, the birds were slaughtered at 14 weeks of age, at which point
they weighed about two pounds. Today's broilers are slaughtered at 7
weeks and weigh between four and six pounds.
A large part of that change can be traced to the increased use of drugs,
which in addition to treating sick birds are used nontherapeutically to
prevent disease and help promote growth. According to the Union of
Concerned Scientists (UCS), tetracycline, penicillin, erythromycin and other
antimicrobials important to human use are among those used extensively in
livestock.
Of course, no one begrudges farmers keeping their poultry healthy. It is the
preventative and growth-promotion drug use that has everyone from the
World Health Organization and the Centers for Disease Control and
Prevention to the Union of Concerned Scientists and the Center for Science
in the Public Interest demanding government usage guidelines and
restrictions.
A look at some recent reports and trends illustrates why health professionals
and others are increasingly concerned. Each year an estimated 1.4 million
human salmonella infections occur in the U.S., causing an estimated 80,000
to 160,000 people to seek medical attention, resulting in 16,000
hospitalizations and nearly 600 deaths. According to the CDC, in 1999,
salmonella and campylobacter comprised the lion's share -- almost 82
percent -- of the total food-borne illness cases.
Both of these diseases are increasingly associated with poultry. Studies
show that campylobacter grows best at the body temperature of a bird,
which can carry it without becoming ill. More than half the raw chicken in
the U.S. has campylobacter in it, according to www.factoryfarming.com, a
website devoted to the agriculture industry.
The CDC notes that most human salmonella infections come from the
ingestion of contaminated food, especially those of animal origin. An
estimated 20 percent of retail poultry is contaminated with salmonella.
As anyone who has suffered from food poisoning knows, these diseases are
not pleasant. People with campylobacteriosis typically have diarrhea,
cramping, abdominal pain and a fever within two to five days of exposure.
The diarrhea may be bloody and accompanied by nausea and vomiting, with
the symptoms typically lasting one week. Salmonella is a bacterial infection
of the intestinal tract causing nausea, vomiting, abdominal cramps, diarrhea,
fever, chills, weakness and exhaustion.
To be fair, the incident rates themselves can make the hype seem a tad
shallow, especially when you consider the sheer number of meals eaten daily
by the U.S. population. But what can be merely unpleasant in a relatively
healthy person can become potentially life-threatening in the young, whose
immune systems are typically less developed, and in the elderly or
immuno-suppressed. It is these people who typically seek medical attention
for these diseases -- and who are more likely to die if the antibiotics to cure
them don't work. Critics also worry that these trends could be the beginning
of what might ultimately, when tied in with overuse in human medicine, be a
return to a pre-antibiotic world.
In 1990 and 1995 the CDC found that 40 percent of people with salmonella
infections who sought medical attention were treated with antimicrobial
agents. Ciprofloxacin, a fluoroquinolone, was the most commonly
prescribed antibiotic. Enrofloxacin, ciprofloxacin's counterpart for animals,
has been given to U.S. poultry since 1995.
In humans, fluoroquinolones are considered one of the most valuable
antimicrobial drug classes because they are effective against a wide range of
bacterial infections, in particular food-borne infections often resistant to
other microbials. People understandably became worried when reports from
scientific and public-health communities began noting more occurrences of
fluoroquinolone-resistant campylobacter infections, especially since no
resistant strains had been recorded prior to the use of this class of antibiotic
in poultry.
As a result of this new disturbing development, last year the FDA's Center
for Veterinary Medicine proposed to withdraw approval of enrofloxacin in
poultry. After Bayer, the company that manufacturers it, complained,
however, the FDA held off. The proposal is still under review. Meanwhile,
sarafloxacin, another fluoroquinolone used in poultry since 1995, has been
taken off the market.
But these are not the only problem drugs. In April, the FDA's Center for
Veterinary Medicine decided to conduct a quantitative risk assessment on
the human health impact of the development of the streptogramin-resistant
enterococcus in humans and its association with the use of virginiamycin in
food-producing animals. Enterococci are bacteria in a normal intestinal tract
that can cause infection if they get out of their normal environment.
Virginiamycin has been used on livestock since 1974. The use of Synercid,
which is closely related, in humans was only approved in 1999 but may
already be running into trouble. Scientists say the effectiveness of Synercid,
an injectable drug of last resort for the treatment of serious or
life-threatening vancomycin-resistant infections, is at risk because of the use
of virginiamycin as a growth promoter in chickens and pigs in the U.S.
Virginiamycin is found in as much as 50 percent of supermarket chicken,
turkey and pork.
In Europe virginiamycin, as well as three other growth-promoting antibiotics,
has already been banned, following recommendations from the World
Health Organization.
Another area of concern is vancomycin-resistant enterococci (VRE)
infection. In Europe, VRE has been isolated from raw poultry products
associated with the use of avoparcin as a feed additive. Avoparcin is not
used in the U.S. nor has VRE been isolated from poultry at this time.
However, University of Maryland professor Glenn Morris recently reported
the isolation of VRE in commercial chicken feed, underscoring the increasing
wide environmental distribution of this organism.
The discovery is particularly disturbing given that vancomycin is the
antibiotic of last resort, the only remaining drug effective against the most
deadly of all hospital-acquired infections: methicillin-resistant staphylococcus
aureus, according to an article in this month's Scientific American. Also,
once a patient is colonized with VRE -- and survives -- he is colonized for
life. To date, VRE been identified in 33 states.
Those in the industry dismiss these trends as so much hype. The Animal
Health Institute, for instance, disputes the figures put out by the Union of
Concerned Scientists. The institute, which is a U.S. trade association
representing manufacturers of animal health care products, pharmaceuticals,
vaccines and feed additives, estimates nontherapeutic use of antibiotics at
17.8 million pounds total for all animals.
Besides, the preventative measures are well worth it, says Richard Lobb,
public relations director of the National Chicken Council, a trade association
to which over 90 percent of chicken producers belong. "The birds coming
into the processing plant today are the healthiest they've ever been," he says.
"We believe our use is responsible and limited," Lobb continues. "All this is
approved by the FDA. Any trace of the drug is gone by the time the bird is
processed. We feel our industry, pork and others are being blamed for
antibiotic resistance problems (created by human misuse). The route of
transmission of antibiotic-resistant pathogens is a rather long and tenuous
one."
Others who are in the barnyards agree. "Our perception of the risk is way
off from the reality," UConn's Darre says. "Risk assessment vs. risk
perception have to get in line somehow.
"If it was half as bad as the critics said, we'd all be dead years ago," he
continues. Darre notes, for instance, that the government has strict guidelines
about antibiotic withdrawal. Farmers must wean poultry and other animals
from the antibiotics, whether therapeutic or nontherapeutic, a certain time
before they can be slaughtered. "The sky is falling to a certain extent but not
to the extent they say it is. There are no proven facts that eating antibiotics
makes humans resistant. The number-one problem is overuse and misuse by
humans."
In the meantime, critics are calling for change -- or at least more review. In
"Hogging It," the Union of Concerned Scientists suggests that the FDA
establish a system so that companies that sell antimicrobials for food animals
or that mix them in animal feed or water must provide annual reports on the
quantities sold. This information should be broken out by species and
antimicrobial, the scientists say, and the USDA should improve
completeness and accuracy of its periodic surveys of antimicrobial use in
livestock production.
Others would like the federal government to speed up implementation of the
Public Health Action Plan to Combat Antimicrobial Resistance. Under this
plan the government would create a monitoring system, improve surveillance
and coordinate national surveillance.
Meanwhile, there is another tactic already in effect that might help. Called
competitive exclusion, this procedure takes the microflora from healthy adult
chickens and gives it to baby chicks. "It gives them all the microorganisms
they need and excludes the bad ones," says professor Darre, noting that the
procedure helps give chicks healthier starts without the drugs. "It will help
alleviate the fear."
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