(Press-News.org) July 12, 2023
Bacterium Associated With Disease Found in N.C. Chiggers
EMBARGOED FOR RELEASE UNTIL NOON EDT ON WEDNESDAY, JULY 12
A bacterium that causes a disease called scrub typhus – a disease not previously reported in the United States – has been detected in North Carolina, according to a new study by researchers at North Carolina State University and UNC-Greensboro.
The researchers stress that scrub typhus, which can cause fever, headache and body aches – and can be fatal if left untreated by antibiotics – has not yet been detected in animals or people in the state.
The NC State researchers detected the bacterium – the genus is Orientia in the family Rickettsiaceae – at a high frequency while testing free living, larval (ready to bite) trombiculid mites, commonly called chiggers, in several different recreational parks in North Carolina.
“We wanted to see if chiggers in the United States carried Orientia,” said Loganathan Ponnusamy, an NC State principal research scholar in entomology and co-corresponding author of a paper that describes the research. “We haven’t in the past had the diagnostic tools to test for this specific bacterium at the genus level.”
“We set a black tile on the ground in 10 different North Carolina state parks and picked up chiggers as they crossed the tile. Microbiome studies allowed us to characterize all the bacteria in the chiggers. One park showed a 90% positivity rate for the bacterium (nine out of 10 chiggers captured); another showed an 80% positivity rate (eight of 10 chiggers captured). Other parks showed positivity rates of just 10%.”
Trombiculid mites are only parasitic in their larval stage. They search for vertebrate hosts – including humans – to bite, Ponnusamy says.
“Chiggers can spread bacteria to people or rodents when they bite but can also pass bacteria to future generations of mites through their eggs,” he added.
The researchers say that scrub typhus presents symptoms similar to those of Rocky Mountain spotted fever, a disease generally ascribed to tick bites.
Scrub typhus is found more commonly in Asia and the Pacific, but in recent years has been detected in Africa and the Middle East. It is uncertain whether spread is caused by people or goods carrying chiggers from one place to another.
“We don’t know if this is a recent introduction into the state or if the bacterium has been here for years,” said R. Michael Roe, William Neal Reynolds Distinguished Professor of Entomology at NC State and co-author of the paper. “We also don’t know if the infected chiggers found in North Carolina actually will cause disease; this has to be determined in future work.”
“We also don't have information about whether the chigger infection rate is decreasing or increasing,” said Kaiying Chen, a postdoctoral research scholar at NC State and lead author of the paper.
The NC State and UNC-Greensboro researchers are resampling chiggers in the recreational park sites to see if the reported findings remain consistent.
The paper appears in the journal Emerging Infectious Diseases. Other co-authors include Nicholas V. Travanty and Charles S. Apperson from North Carolina State University; Reuben Garshong and Gideon Wasserberg from the University of North Carolina Greensboro; and Dac Crossley from the Georgia Museum of Natural History.
Funding was provided by a grant from the National Institutes of Health, National Institute of Allergy and Infectious Diseases (grant no. 1R03AI166406-01); a grant from the Southeast Center for Agricultural Health and Injury Prevention, and from the Department of the Army, U.S. Army Contracting Command, Aberdeen Proving Ground, Natick Contracting Division, Ft Detrick MD. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the position or the policy of the Government and no official endorsement should be inferred.
- kulikowski -
Note to editors: The abstract of the paper follows.
“Detection of Orientia Spp. Bacteria in Field-Collected Free-Living Eutrombicula Chigger Mites, USA”
Authors: Kaiying Chen, Nicholas V. Travanty, Charles S. Apperson, R. Michael Roe, and Loganathan Ponnusamy, North Carolina State University; Reuben Garshong and Gideon Wasserberg, University of North Carolina Greensboro; Dac Crossley, Georgia Museum of Natural History
Published: July 12, 2023 in Emerging Infectious Diseases
DOI: 10.3201/eid2908.230528
Abstract: Scrub typhus, a rickettsial disease caused by Orientia spp., is transmitted by infected larval trombiculid mites (chiggers). We report the molecular detection of Orientia species in free-living Eutrombicula chiggers collected in an area in North Carolina, United States, in which spotted fever group rickettsiae infections are endemic.
END
Researchers at McLean and Mass General Hospital demonstrated that a transplant surgical procedure (called “needle trauma”) triggers a profound immune response and causes the death of most grafted dopamine neurons
They also found that co-transplantation of neuronal cell therapy with host regulatory T cells resulted in effective suppression of needle trauma and significant improvement in the survival and recovery of grafts
Findings suggest a path for the ‘realistic’ use of cell therapy to treat neurodegenerative disorders
Cell therapy holds promise as a new treatment for Parkinson’s disease but, in many trials to date, most transplanted dopamine ...
About The Study: This study found that the joint exposure of unequal income distribution and lack of social mobility was associated with additional risks for deaths of despair (deaths from suicide, drug overdose, and alcohol-related liver disease), suggesting that addressing the underlying social and economic conditions is crucial in responding to the epidemic of deaths of despair.
Authors: Chun-Tung Kuo, Ph.D., of National Taiwan University in Taipei, is the corresponding author.
To access the embargoed study: Visit our ...
About The Study: Into the second year of the pandemic, mental health emergency department visits increased notably among adolescent females, and there was an increase in prolonged boarding (waiting in an emergency department or medical inpatient unit) of youth awaiting inpatient psychiatric care. Interventions are needed to increase inpatient child psychiatry capacity and reduce strain on the acute mental health care system.
Authors: Haiden A. Huskamp, Ph.D., of Harvard Medical School in Boston, is the corresponding author.
To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/
(10.1001/jamapsychiatry.2023.2195)
Editor’s ...
CAMBRIDGE, MA -- The ocean’s color has changed significantly over the last 20 years, and the global trend is likely a consequence of human-induced climate change, report scientists at MIT, the National Oceanography Center in the U.K., and elsewhere.
In a study appearing today in Nature, the team writes that they have detected changes in ocean color over the past two decades that cannot be explained by natural, year-to-year variability alone. These color shifts, though subtle to the human eye, have occurred over 56 percent of the world’s oceans — an expanse that is larger than ...
Like its viral cousins, a somewhat parasitic DNA sequence called a retrotransposon has been found borrowing the cell’s own machinery to achieve its goals.
In a new work appearing online Wednesday in the journal Nature, a Duke University team has determined that retrotransposons hijack a little-known piece of the cell’s DNA repair function to close themselves into a ring-like shape and then create a matching double strand.
The finding upends 40 years of conventional wisdom saying these rings were just a useless by-product of bad gene copying. It may also offer new insights into cancer, viral infections and immune responses.
Retrotransposons are segments ...
SAN FRANCISCO, CA (July 12, 2023) — In a paper published today in Nature, researchers from the California Academy of Sciences, University of São Paulo, University of Oxford, University of Exeter, and other collaborators reveal the extent of plastic pollution on coral reefs, finding that debris increases with depth, largely stems from fishing activities, and is correlated with proximity to marine protected areas.
Through underwater visual surveys spanning more than two dozen locations across the Indian, Pacific, and Atlantic ...
The function of mast cells, which are part of the immune system, is still a mystery. Scientists at the German Cancer Research Center (DKFZ) have now shown in mice: mast cells function as a sensor that signals the animals to avoid antigens, including harmful allergens, and thereby protect themselves from health-threatening inflammatory reactions. The findings were published in the journal Nature.
Mast cells are found primarily in tissues that separate the outside and inside worlds of the body, such ...
In a new study, published today (12 July) in Nature, researchers have produced the most detailed and comprehensive human Heart Cell Atlas to date, including the specialised tissue of the cardiac conduction system - where the heartbeat originates.
The multi-centre team is led by the Wellcome Sanger Institute and the National Heart and Lung Institute at Imperial College London, and has also presented a new drug-repurposing computational tool called Drug2cell, which can provide insights into the effects of drugs on heart rate.
This study is part of the international Human Cell Atlas* ...
The number of young people in the United States visiting hospital emergency departments for mental health crises increased sharply during the second year of the COVID-19 pandemic, according to a study led by researchers from the Department of Health Care Policy in the Blavatnik Institute at Harvard Medical School. The findings are published Jul 12 in JAMA Psychiatry.
These results come amidst growing national concern about a crisis in youth mental health and provide important new details about how young people with mental health problems such as self-harm ...
LAWRENCE, Kan. — Around 14 million tons of plastic end up in the ocean every year. But that is not the only water source where plastic represents a significant intrusion.
“We found microplastics in every lake we sampled,” said Ted Harris, associate research professor for the Kansas Biological Survey & Center for Ecological Research at the University of Kansas.
“Some of these lakes you think of as clear, beautiful vacation spots. But we discovered such places to be perfect examples of the link between plastics and humans.”
Harris ...