CONTACT: JENNIFER CRONIN
2130 Medical Laboratories
Iowa City IA 52242
(319) 335-5661; fax (319) 335-9917
Release: March 5, 1999
Iowa at or below national averages in antibiotic resistant bacteria,
UI research shows
IOWA CITY, Iowa -- After six months of surveillance, University of Iowa
investigators have found that in some cases Iowa fares better than other
parts of the country when it comes to the effectiveness of antibiotics
in fighting bacterial infections.
The first two quarters of data from a UI initiative show that Iowa does
not have a major problem with antibiotic resistance against enterococcus
and gram-negative bacteria, both of which are associated with gastrointestinal
As for the antibiotic resistance of Staphylococcus aureus -- which cause
skin infections -- and Streptococcus pneumoniae -- which cause middle ear
infections, sinusitis, bronchitis, pneumonia and meningitis -- Iowa mirrors
the national averages, said Gary Doern, Ph.D., UI professor of pathology.
On July 1, 1998, Doern, along with UI professors of pathology Ronald
Jones, M.D., and Michael Pfaller, M.D., began the first-ever, statewide
tracking of the emergence of antibiotic resistance. During the five-year
study -- titled "Emerging Infections and the Epidemiology of Iowa
Organisms: A Prospective, Statewide, Longitudinal Surveillance Study of
Antimicrobial Resistance" -- the UI researchers will develop a database
of bacterial samples collected from 15 participating medical centers from
across the state. The investigating team wants to determine the magnitude
and scope of antibiotic resistance in Iowa, measure the phenomenon's change
over the long term, identify appropriate solutions to combat the resistance
and then implement those solutions.
While Doern said at this point it is difficult to say why Iowa does
not follow the national trend for enterococcus and gram-negative bacteria,
he does offer a couple of possible explanations. First, there might be
more prudent use of antibiotics in Iowa than elsewhere. Second, the infection-control
practices in hospitals -- where these bacteria are most often found --
might prevent infections from occurring in the first place.
"These are over-simplistic explanations, but they are at least
two factors that might explain what we've seen up until this point,"
The statewide surveillance is only one of the UI's investigation into
the antibiotic-resistant-bacteria problem. In January, Doern and his colleagues
also started a nationwide project looking at the issue in chronic-care
"We don't have any idea about the scope and the magnitude of the
problem in chronic-care facilities," Doern said. "There appears
to be a bigger problem of antibiotic resistance with patients in chronic-care
facilities than there is in the general population, but there isn't a lot
of good, systematic data upon which to even make that case. We have to
conduct this surveillance to find out whether that is true and to determine
the problem's scope and magnitude."
Once the researchers understand the problem, they can begin to formulate
solutions to tackle it, Doern said.
The five-year, roughly $1 million investigation, called the Omega Study,
involves nine medical centers from across the country, each representing
20 to 30 affiliated chronic-care facilities. The medical centers collect
and send samples from the facilities to the UI lab for analysis.
The issue of antibiotic resistant bacteria is an important one that
needs more attention, Doern said. Many bacteria are developing resistance
to antibiotics, and the emergence of a "superbug" resistant to
all treatments is a real possibility unless health care professionals and
the public take corrective steps soon.
It is a process of survival of the fittest, Doern stated when describing
why bacteria are becoming more and more resistant. For example, when scientists
introduced the widely used antibiotic penicillin in the 1940s, the drug
was effective against almost all strains of Staphylococcus aureus. In the
United States today, 95 percent of the strains of this important cause
of human infections are penicillin resistant.
"If you have two bacteria and one is penicillin susceptible and
one is penicillin resistant, the penicillin-resistant organism has a selective
advantage," Doern said.
The factors creating antibiotic resistance are multifaceted, in some
cases poorly defined and in other cases completely obscure. However, one
of the most widely accepted contributors is the use of antibiotics themselves.
"In a very real way, antibiotics are a double-edged sword,"
Doern said. "Obviously, they are essential medicines in the treatment
of infections, but they have a serious downside. The very use of those
drugs contributes to resistance that in the end renders the antibiotics
Limiting antibiotic usage will require physician education, public communication
and better diagnostic tests, Doern said.
"When a physician is confronted with an individual patient in whom
it is not absolutely clear that an infection is present, where does he
or she want to err?" Doern asked. "You want to err on the side
of being conservative and that is going to prompt you to use antibiotics.
What we need is better, simpler, less expensive, non-invasive diagnostic
tests that provide accurate information more rapidly. Then physicians can
make more reasonable judgments in terms of antibiotic therapy."
However, the most effective means of dealing with the antibiotic resistance
problem is to prevent infections from occurring in the first place, Doern
said. That is going to take better infection control practices and the
use of vaccines.