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Reference Terms
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Pathogen

A pathogen or infectious agent is a biological agent that causes disease or illness to its host. The term is most often used for agents that disrupt the normal physiology of a multicellular animal or plant. However, pathogens can infect unicellular organisms from all of the biological kingdoms. There are several substrates and pathways whereby pathogens can invade a host. The human body contains many natural defenses against some of common pathogens in the form of the human immune system and by some "helpful" bacteria present in the human body's normal flora. Some pathogens have been found to be responsible for massive amounts of casualties and have had numerous effects on afflicted groups. Today, while many medical advances have been made to safeguard against infection by pathogens, through the use of vaccination, antibiotics and fungicide, pathogens continue to threaten human life. Social advances such as food safety, hygiene, and water treatment have reduced the threat from some pathogens.

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Health & Medicine News

February 5, 2026

People who switch to a fully unprocessed diet don’t just eat differently—they eat smarter. Research from the University of Bristol shows that when people avoid ultra-processed foods, they naturally pile their plates with fruits and vegetables, ...
Kidney disease often creeps in silently, and many patients aren’t diagnosed until major damage is already done. New research shows that even “normal” kidney test results can signal danger if they’re unusually low for someone’s age. By ...
Researchers have created the first complete map showing how hundreds of mutations in a key cancer gene affect tumor growth. By testing every possible mutation in a critical hotspot, they found that some changes barely boost cancer signals, while ...
Advanced care provided by air ambulance teams was linked to higher survival rates in major trauma patients. Researchers found that more people survived than predicted by standard models, including many with severe injuries and low chances of ...
As bird flu continues to circulate in animals and spill over into humans, researchers are racing to stop it before it adapts to spread widely between people. A new nasal spray vaccine showed strong protection against H5N1 in animal tests, ...
Popular weight-loss drugs like Ozempic and Wegovy can dramatically curb appetite, but experts warn many users are flying blind when it comes to nutrition. New research suggests people taking these medications may not be getting enough guidance on ...
A massive Swedish study tracking nearly 28,000 people for 25 years found an unexpected link between full-fat dairy and brain health. Among adults without a genetic risk for Alzheimer’s, eating more full-fat cheese was associated with a noticeably ...
Scientists are digging into why heart disease risk in type 2 diabetes differs between men and women—and sex hormones may be part of the story. In a large Johns Hopkins study, men with higher testosterone had lower heart disease risk, while rising ...
Sound machines may not be the sleep saviors many believe. Researchers found that pink noise significantly reduced REM sleep, while simple earplugs did a better job protecting deep, restorative sleep from traffic noise. When pink noise was combined ...
As we age, our cells don’t just wear down—they reorganize. Researchers found that cells actively remodel a key structure called the endoplasmic reticulum, reducing protein-producing regions while preserving fat-related ones. This process, driven ...
Plants make chemical weapons to protect themselves, and many of these compounds have become vital to human medicine. Researchers found that one powerful plant chemical is produced using a gene that looks surprisingly bacterial. This suggests plants ...
Chronic stress can damage the gut’s protective lining, triggering inflammation that may worsen depression. New research shows that stress lowers levels of a protein called Reelin, which plays a key role in both gut repair and brain health. ...

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