28
ANTIBIOTIC
RESISTANCE
&
STEWARDSHIP
Gene that makes salmonella resistant
to antibiotics found in US patient
By Anuja Vaidya
R
esearchers have found a gene that makes the salmonella bacteria
resistant to last-resort antibiotics in a human patient in the U.S.
The research team, from North Carolina State University in Raleigh, identi-
fied the gene mcr-3.1, which previously had only been found in people in
Asia. The gene gives salmonella resistance to colistin, an antibiotic used as
a last resort treatment for multidrug-resistant salmonella infections.
Researchers performed genome sequencing on 100 clinical human
stool samples taken from the Southeastern U.S. between 2014 and
2016. In one of the samples, they found the colistin-resistant mcr-3.1
gene. The person's whose sample contained the gene had traveled to
China two weeks before contracting a salmonella infection.
"The positive sample was from 2014, so this discovery definitely has im-
plications for the spread of colistin-resistant salmonella in the U.S.," said
Siddhartha Thakur, PhD, professor and director of global health at North
Carolina State University and corresponding author of the research.
The research, supported by the National Institutes of Health/Food and Drug
Administration, was published in the Journal of Medical Microbiology. n
1 antibiotic course could create
resistance in children, study finds
By Anne-Marie Kommers
A
single course of antibiotics could increase antibiotic resis-
tance in children, according to a study published in Clinical
Infectious Diseases.
To conduct the study, researchers studied families with at least two chil-
dren ages 6-59 months in two rural communities in Burkina Faso, a coun-
try in West Africa. Researchers randomly assigned 124 children to receive
either amoxicillin, azithromycin, cotrimoxazole or a placebo in July 2017.
Rectal samples taken five days after a child's last antibiotic treatment
found azithromycin made children twice as likely to have genetic re-
sistant determinants to macrolide antibiotics, suggesting azithromycin
could cause more drastic changes in the gut microbiome than other
antibiotics. All antibiotics increased resistance determinants to sulfano-
mide antibiotics compared with the placebo.
Researchers cautioned that higher numbers of resistance genes do not
necessarily create functional resistance, according to Healio.
"Whether this eventually translates to infections that are more difficult
to treat is unknown," Catherine Oldenburg, PhD, an infectious disease
epidemiologist at the UC San Francisco, told the publication. n
Patient, physician
education can cut
inappropriate
antibiotics
by 32%
By Mackenzie Bean
E
ducating physicians and patients about
safe antibiotic practices could cut
inappropriate prescriptions by nearly
one-third, according to a study published
in Academic Emergency Medicine.
Researchers from Sacramento, Calif.-based
UC Davis Health conducted the CDC-funded
study. ey randomly assigned 292 clinicians
from nine emergency departments and urgent
care centers in California and Colorado to use
one of two educational strategies to reduce an-
tibiotic use. Researchers then reviewed 44,820
patient visits for viral acute respiratory infec-
tions to track the number of inappropriate
antibiotics administered to patients between
2017 and 2018.
One approach involved giving patients and
providers educational materials on safe antibi-
otic use, while also designating a physician to
champion the efforts. e second approach gave
physicians behavioral "nudges," in which they
received feedback on prescribing rates and saw
how they compared to peers.
In total, antibiotic prescriptions for viral
infections fell from 6.2 percent to 2.4 percent
during the study period. Researchers found
inappropriate prescriptions dropped from 2.2
percent to 1.5 percent over the same period,
marking a 31.8 percent decrease. e second,
more aggressive educational approach involving
behavioral nudges was not more effective at
reducing antibiotic overuse.
"We found education with an on-site champion
reduced inappropriate antibiotic use by a third
across the board," Larissa May, MD, senior
author and professor of emergency medicine at
UC Davis Health, said in a news release. "Our
study shows that this relatively simple approach
can get us to near-zero inappropriate antibiotic
use for acute respiratory infections." n
