Antibiotic use addressed by U.S.D.A., academics
of Article: http://www.meatnews.com/news/headline_stories.asp?ArticleID=101364
(MEATPOULTRY.com, April 06,
by Bernard Shire
WASHINGTON — "The
rapid emergence of antibiotic resistant pathogens has major public health
and social impact," said Dr. Hua H. Wang, a food scientist at Ohio State
University, Columbus, Ohio, at a conference here addressing the growing
tendency of disease-causing organisms to be able to resist antibiotic drugs
and drug therapy meant to fight them, both in animals and humans.
The April 2-3 conference,
"Minimizing Antibiotic Resistance Transmission Through the Food
Chain," was jointly sponsored by the Cooperative State Research,
Education, and Extension Service (CSREES) of the U.S. Department of
Agriculture, the Ohio State University Extension, and Ohio Agriculture
Research and Development Center. Leading the conference, in addition to Dr.
Wang, were Dr. John N. Sofos, Center for Meat Safety and Quality, Colorado
State University, Fort Collins, Colorado, and Dr. Thaddeus B. Stanton, of
USDA’s Agricultural Research Service, Ames, Iowa.
Dr. Wang said in the last
couple of decades, an intensive discussion on the correlation between the
use of antibiotics in human and veterinary medicine, food animal
production, agriculture applications and the development of resistance in
human pathogens has been a hot topic in science which has led to several
government policy changes in both the E.U. and the U.S. "The problem
of antibiotic resistance still exists," she said.
Speakers at the
conference noted bacteria and other microorganisms causing infections are
remarkably resilient and can develop ways to survive drugs meant to weaken
them. This antibiotic resistance is due largely to the increasing use of
antibiotics, although several speakers noted the problem is complex and can’t
be tied simply to this use. Speakers pointed out that that food-producing
animals are given antibiotic drugs for important therapeutic, disease
prevention or production reasons. However, these drugs can cause microbes
to become resistant to medications used to treat human illnesses,
ultimately making some human sicknesses more difficult to treat.
Does this mean antibiotic use in agriculture should be curtailed? That was
the question addressed by keynote speaker Dr. Abigail Salyers, from the
Department of Microbiology, University of Illinois, Urbana, Illinois. She
said even though antibiotics are usually used at very low concentrations in
agriculture, they can still select for antibiotic-resistant bacteria.
bacteria then enter the food supply. A potential hazard of consuming such
food is that resistant bacterial pathogens such as Salmonella typhinurium
can cause disease," she said. "Another potential hazard seldom
considered but probably more serious is the transfer of resistance genes
from bacteria passing through the human intestinal tract to bacteria
normally occupying that site. Such bacteria are common causes of
post-surgical infections." There is not yet enough data to enable
scientists to quantify the risks associated with such scenarios, but there
is evidence such scenarios are possible, she added.
In speaking about
antibiotic resistance in meats and other foods, Dr. Sofos pointed out
antimicrobials find numerous beneficial applications in human, animal and
plant health, as well as in food production. Their selective pressure,
however, may lead to the emergence of resistant pathogen strains.
"Therefore, it is
important to maintain the ability of pathogens to be affected by
antimicrobials," he said. "The best approach to minimizing antibiotic
resistance negative impact is through risk assessments. Major
recommendations for control include prevention of disease; use of
antibiotics of lesser importance to human medicine, and treatment with
alternative methods, including vaccines."
Dr. Sofos noted in
tracking resistance of Salmonella to antibiotics in eight beef plants,
resistance occurred mostly on cattle hides, but only a small amount of
resistance to antibiotics existed on beef carcasses. "There was more
resistance by the Campylobacter pathogen in poultry," he noted.
"Research should also focus on the potential of antibiotics to enter
animal production environments through waste streams."