Evolution of staph 'superbug' traced between humans and food animals
A strain of the potentially deadly antibiotic-resistant bacterium known as MRSA has jumped from food animals to humans, according to a new study involving two Northern Arizona University researchers.
Paul Keim, Regents’ professor and director of NAU’s Center for Microbial Genetics and Genomics, and Lance Price, NAU faculty member and director of the Center for Food Microbiology and Environmental Health at the Translational Genomics Research Institute, collaborated with scientists at 20 institutions around the world on the study published today in the online journal mBio.
The TGen-led research utilized whole genome sequencing to study 89 genomes from humans and animals — including turkeys, chickens and pigs — with samples from 19 countries on four continents.
The research focused on methicillin-resistant Staphylococcus aureus CC398, also known as pig MRSA or livestock-associated MRSA because it most often infects people with direct exposure to swine or other food animals. It is likely that MRSA CC398 started as an antibiotic-susceptible strain in humans before it jumped to food animals.
After transferring to food animals, MRSA CC398 became resistant to two important antibiotics, tetracycline and methicillin, which are used for treating staph infections. The resistance likely is a result of the routine antibiotic use that characterizes modern food-animal production. The animals commonly are given antibiotics to prevent infection and promote growth.
Keim, who also serves as director of TGen’s Pathogenic Genomics Division, said the study describes evolution in action. "The most powerful force in evolution is selection. And in this case, humans have supplied a strong force through the excessive use of antibiotic drugs in farm animal production. It is that inappropriate use of antibiotics that is now coming back to haunt us.”
Price, the study’s lead author, said the research was “like watching the birth of a superbug—it is simultaneously fascinating and disconcerting.” He said that while this strain of MRSA was discovered less than a decade ago it appears to be spreading very quickly.
“Our findings underscore the potential public health risks of widespread antibiotic use in food animal production,” Price said. “Staph thrives in crowded and unsanitary conditions. Add antibiotics to that environment and you’re going to create a public health problem.”
NAU Office of Public Affairs
TGen Senior Science Writer
Cynthia Brown | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
Computer simulation shows how the icy moon heats water in a porous rock core
Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....