An epidemic is a phenomenon characterized by the occurrence of cases of a specific disease, infection, or health-related event in a population, community, or region at levels significantly exceeding the expected baseline during a defined time period. It reflects a dynamic imbalance between pathogen transmission, host susceptibility, and environmental or social determinants. Epidemics are described mathematically using measures such as the basic and effective reproduction numbers (R₀, Rₑ), incidence rates, and epidemic curves, and are driven by mechanisms including person-to-person transmission, vector-borne spread, or common-source exposure, often necessitating targeted public health interventions for containment and mitigation.
A host that sheds an abundance of parasites might seem like an obvious disease-spreading threat. But new research suggests that shedding large volumes of parasites does not dictate transmission efficiency—and "super-shedders" ...
Australia is now confronting an outbreak of a deadly bird flu strain. As of Monday, the highly pathogenic H5N1 virus had been detected in 78 wild birds across mainland Australia. Until now, there had been no evidence of a ...
Ecology
Aug 5, 2026
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10
Researchers from Trinity College Dublin have recovered and analyzed the first ancient smallpox virus genomes ever identified in the Americas, providing the strongest direct evidence to date that the disease was introduced ...
Evolution
Jul 30, 2026
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34
St. Louis is a plant science powerhouse, but outside the neatly tended rows of crops and gleaming greenhouses sits another treasure trove of biological data: The wild plants tucked into yards, sidewalk cracks, ditches and ...
Plants & Animals
Jul 20, 2026
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8
New roads bring changes to the regions they traverse. They can enable job opportunities, access to medicine and health care, and electricity. But they also disrupt local ecosystems and can have surprising consequences for ...
Environment
Jul 8, 2026
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31
The scenes are biblical. Tens of thousands of rodents scattering across canola fields, behind sheds, into machinery. River fish with bellies full of mice. Carcasses littering the street, the sidewalk, outside your home. In ...
Ecology
Jul 2, 2026
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300
A pathogenic strain of bird flu killed more than 13,000 elephant seal pups after infecting a breeding colony on a sub-Antarctic volcanic island, Australian scientists said Thursday.
Ecology
Jun 18, 2026
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21
Johanna Harvey, an assistant professor of wildlife disease ecology at the University of Rhode Island, has described bird flu in public presentations as a quiet virus with loud consequences. Now, she's published a new paper ...
Ecology
May 27, 2026
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15
A 2021 outbreak of leptospirosis that sickened more than 200 dogs in Los Angeles County reveals critical gaps in vaccination practices and raises broader concerns about the spread of the disease between animals and people, ...
Cell & Microbiology
May 26, 2026
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17
New research from a Texas A&M College of Agriculture and Life Sciences doctoral graduate could help producers better protect poultry flocks from disease outbreaks while reducing costs.
Biotechnology
May 20, 2026
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17
