(Press-News.org) DNA sequencing of bacteria found in pigs and humans in rural eastern North Carolina, an area with concentrated industrial-scale pig-farming, suggests that multidrug-resistant Staphylococcus aureus strains are spreading between pigs, farmworkers, their families and community residents, and represents an emerging public health threat, according to a study led by researchers at the Johns Hopkins Bloomberg School of Public Health.
S. aureus is commonly found in soil and water, as well as on the skin and in the upper respiratory tract in pigs, other animals, and people. It can cause medical problems from minor skin infections to serious surgical wound infections, pneumonia, and the often-lethal blood-infection condition known as sepsis. The findings provide evidence that multidrug-resistant S. aureus strains are capable of spreading and possibly causing illness in and around factory farm communities in the U.S.--a scenario the authors say researchers should continue to investigate.
The study was published online February 22 in Emerging Infectious Diseases, a journal published by the U.S. Centers for Disease Control and Prevention.
The researchers in recent years have been collecting samples of S. aureus from pigs, farmworkers, farmworkers' family members, and community residents--including children--in the top pig-producing counties in North Carolina. For the study, they sequenced the DNA from some of these samples to determine the relation of the strains found in pigs and people. They found that the strains were very closely related, providing evidence for transmission between pigs and people. Most of the strains carried genes conferring resistance to multiple antibiotics.
"We found that these livestock-associated S. aureus strains had many genes that confer resistance to antimicrobial drugs commonly used in the U.S. industrialized pig production system," says study first author Pranay Randad, PhD, a postdoctoral researcher in the Bloomberg School's Department of Environmental Health and Engineering.
"These findings warrant future investigations into the transmission dynamics in nearby communities and disease burden associated with these strains in the United States," says study senior author Christopher Heaney, PhD, associate professor in the same department.
Epidemiologists have long suspected that S. aureus and other bacteria are transmitted from humans to pigs on factory farms, and thereafter evolve antibiotic resistance within the pigs. The animals are routinely given antibiotics to prevent outbreaks in their dense concentrations on factory farms. The drug-resistant bacterial strains may then be transmitted back to humans, becoming a potentially serious source of disease.
In recent years, Heaney and colleagues have been gathering S. aureus isolates from pigs and farmworkers at factory-scale pig farms in North Carolina, one of the leading pig-farming states. Their research has shown that livestock-associated strains of S. aureus, many of them antibiotic-resistant strains, can be found not only in pigs but also in farmworkers, their family members, and residents living nearby.
For the new study they performed whole-genome sequencing on 49 of these S. aureus isolates to characterize these strains at the DNA level and get a more precise picture of their interrelatedness.
One finding was that all these isolates, whether taken from humans or pigs, belonged to a grouping of S. aureus strains known as clonal complex 9 (CC9).
"This CC9 is a novel and emerging subpopulation of S. aureus that not many people have been studying, apart from a few reports in Asia," Randad says.
The researchers also determined from their analysis that the CC9 isolates from North Carolina were closely related, in many cases implying recent transmission between pigs and people. Moreover, virtually all of the isolates that appeared to be involved in transmission between pigs and humans were multidrug resistant, suggesting that diseases these isolates cause could be hard to treat.
The scope of the study didn't include evaluating S. aureus-related disease among people in the affected communities, but one of the pig farmworkers who carried a CC9 isolate in their nose reported a recent skin infection.
"In other countries, such as in Europe, we see a high level of coordinated research on this topic from a public health perspective, with open access to collect bacterial isolates from pigs raised on factory farms, but so far in the U.S. not as much is being done," Randad says.
INFORMATION:
"Transmission of Antimicrobial-Resistant Staphylococcus aureus Clonal Complex 9 between Pigs and Humans, United States" was co-authored by Pranay Randad, Jesper Larsen, Hülya Kaya, Nora Pisanic, Carly Ordak, Lance Price, Maliha Aziz, Maya Nadimpalli, Sarah Rhodes, Jill Stewart, Dave Love, David Mohr, Meghan Davis, Lloyd Miller, Devon Hall, Karen Carroll, Trish Perl, and Christopher Heaney.
Support for the study was provided by the Sherrilyn and Ken Fisher Center for Environmental Infectious Diseases Discovery Program at the Johns Hopkins University School of Medicine; the GRACE Communications Foundation; the National Institute for Occupational Safety and Health, the National Science Foundation, the National Institute of Allergy and Infectious Diseases, and the National Institute of Environmental Health Sciences, among other funding sources.
Researchers from the University of Tennessee, Knoxville, have collaborated on two studies examining the socioeconomic factors involved in the spread of COVID-19.
Professor Alex Bentley and postdoctoral fellow Damian Ruck, both from the Department of Anthropology, joined Josh Borycz, a librarian at Vanderbilt University, to conduct the studies.
"One of our studies considers the global scale of nations and the other uses the national scale for US counties to analyze results during 2020," explained Bentley.
The studies show that the numbers of COVID-19 cases and deaths are significantly affected ...
Two thirds of children use more than one screen at the same time after school, in the evenings and at weekends as part of increasingly sedentary lifestyles, according to new research at the University of Leicester.
An NIHR study of more than 800 adolescent girls between the ages of 11 and 14 identified worrying trends between screen use and lower physical activity - including higher BMI - as well as less sleep.
The use of concurrent screens (termed 'screen stacking') grew over the course of the week - with 59% of adolescents using two or more screens after school, 65% in the evenings, and 68% at weekends.
Some teens reporting using as many as four screens at one time.
But further analysis showed the use of any screen was still detrimental to the indicators ...
A new study from the University of Iowa sought to begin development of a possible approach to reduce the risk that college-aged men engage in sexually aggressive acts or risky sexual behavior.
The study authors, led by Teresa Treat, professor in the Department of Psychological and Brain Sciences at Iowa, developed a 12-point list of sexual assault prevention strategies. The list was created by the researchers based on previous research into risk factors that are associated with sexually aggressive acts--such as heavy alcohol consumption, difficulties reading women's cues, and not seeking consent for sexual activity.
The authors found that 71% of the college-aged men surveyed used the sexual assault prevention strategies on a regular basis over the past year. Yet 15% of the ...
DANVILLE, Pa. - A team of scientists from Geisinger and Tempus have found that artificial intelligence can predict risk of new atrial fibrillation (AF) and AF-related stroke.
Atrial fibrillation is the most common cardiac arrhythmia and is associated with numerous health risks, including stroke and death. The study, published in Circulation, used electrical signals from the heart--measured from a 12-lead electrocardiogram (ECG)--to identify patients who are likely to develop AF, including those at risk for AF-related stroke.
"Each year, over 300 million ...
A new review of existing evidence proposes eight hallmarks of environmental exposures that chart the biological pathways through which pollutants contribute to disease: oxidative stress and inflammation, genomic alterations and mutations, epigenetic alterations, mitochondrial dysfunction, endocrine disruption, altered intercellular communication, altered microbiome communities, and impaired nervous system function.
The study by researchers at Columbia University Mailman School of Public Health, Ludwig Maximilian University, and Hasselt University is published in the journal Cell.
"Every day we learn ...
Patients' electronic health records convey crucial information. The application of natural language processing techniques to these records may be an effective means of extracting information that may improve clinical decision making, clinical documentation and billing, disease prediction and the detection of adverse drug reactions. Adverse drug reactions are a major health problem, resulting in hospital re-admissions and even the death of thousands of patients. An automatic detection system can highlight said reactions in a document, summarise them and automatically report them.
In this context, the Basurto University Hospital and the Galdakao ...
A monoclonal antibody "cocktail" developed at Vanderbilt University Medical Center (VUMC) to neutralize the COVID-19 virus is effective against all known strains, or variants, of the virus, according to a report published in the journal Nature Medicine.
That was one of the findings reported by a multi-institutional team led by researchers at Washington University School of Medicine in St. Louis.
In cell-culture studies, the researchers determined the ability of monoclonal antibodies as well as antibodies isolated from the "convalescent plasma" of previously infected people to neutralize highly transmissible variants of the SARS-CoV-2 virus that have arisen in the United Kingdom, South Africa, Brazil and elsewhere.
In general, most of the monoclonal antibodies that have ...
Can Switzerland, as planned, cut its CO2 emissions to zero by 2050? In a study, researchers at the Paul Scherrer Institute PSI have investigated what measures would be necessary to achieve this reduction and how much it might cost per person.
In August 2019, the Swiss Federal Council decided on an ambitious target to limit climate change: From the year 2050 onward Switzerland should, on balance, discharge no further greenhouse gas emissions. With this commitment, Switzerland meets the internationally agreed goal of limiting global warming to a maximum of 1.5° C compared to the pre-industrial era.
Now a study by the Paul Scherrer Institute, ...
Functioning ecosystems provide the basis for security, basic material needs, health, social interaction and individual liberty. This is how the Millennium Ecosystem Assessment 2005 described it, dividing ecosystem services into the following categories: The provisioning services; goods such as food, water, firewood and timber, the regulating services; pollination, water filtering function of the soil, flood and erosion protection, and the cultural services; recreation, places of inspiration, and education. Many of these services are indirectly and directly linked to the presence of species. For this reason, species conservation is often put forward as a measure for the conservation of vital natural services.
"However, most previous ...
PHILADELPHIA - Intellectual disability puts individuals at higher risk of dying earlier in life than the general population, for a variety of medical and institutional reasons. A new study from Jefferson Health examined how the COVID-19 pandemic has affected this group, which makes up 1-3% of the US population. The study, published today in the New England Journal of Medicine (NEJM) Catalyst, found that intellectual disability was second only to older age as a risk factor for dying from COVID-19.
"The chances of dying from COVID-19 are higher for those with intellectual disability than they are for people with congestive heart failure, kidney disease or lung disease," says lead author Jonathan Gleason, MD, the James D. and Mary Jo Danella ...
