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Flea
Flea is the common name for any of the small wingless insects of the order Siphonaptera. Fleas are external parasites, living by hematophagy off the blood of mammals and birds. In most cases, fleas are just a nuisance to their hosts, but some people and some animals suffer allergic reactions to flea saliva resulting in rashes. Flea bites generally result in the formation of a slightly-raised swollen itching spot with a single puncture point at the center. Fleas can act as a vector for disease. One possible example of this was the bubonic plague, which may have been transmitted between rodents and humans. Murine typhus (endemic typhus) fever, and in some cases tapeworms, Hymenolepis, can also be transmitted by fleas.
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Health & Medicine News
January 26, 2026
Jan. 26, 2026 Home fireplaces and wood stoves are quietly driving a large share of winter air pollution, even though only a small number of households rely on wood heat. Researchers found that wood smoke accounts for over one-fifth of Americans’ winter exposure ...
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Jan. 26, 2026 Cancer doesn’t evolve by pure chaos. Scientists have developed a powerful new method that reveals the hidden rules guiding how cancer cells gain and lose whole chromosomes—massive genetic shifts that help tumors grow, adapt, and survive ...
Jan. 26, 2026 Alzheimer’s may destroy memory by flipping a single molecular switch that tells neurons to prune their own connections. Researchers found that both amyloid beta and inflammation converge on the same receptor, triggering synapse loss. Surprisingly, ...
Jan. 25, 2026 A newly uncovered immune chain reaction in the gut may explain why people with inflammatory bowel disease face a much higher risk of colorectal cancer. Researchers found that a powerful inflammatory signal flips on specialized gut immune cells, ...
Jan. 25, 2026 Scientists are warning that a little-known group of microbes called free-living amoebae may pose a growing global health threat. Found in soil and water, some species can survive extreme heat, chlorine, and even modern water systems—conditions ...
Jan. 25, 2026 Researchers have found that a natural aging-related molecule can repair key memory processes affected by Alzheimer’s disease. The compound improves communication between brain cells and restores early memory abilities that typically fade first. ...
Jan. 25, 2026 Pancreatic cancer may evade the immune system using a clever molecular trick. Researchers found that the cancer-driving protein MYC also suppresses immune alarm signals, allowing tumors to grow unnoticed. When this immune-shielding ability was ...
Jan. 24, 2026 Chronic inflammation may be quietly reshaping the colon and making it more vulnerable to early-onset colorectal cancer. Scientists found that colon tissue in younger patients was stiffer, even in areas that appeared healthy, suggesting these changes ...
Jan. 24, 2026 Aging immune cells may be sabotaging the body from within. Researchers found that macrophages produce a protein that locks them into a chronic inflammatory state, making infections like sepsis more deadly in older adults. Turning off this signal ...
Jan. 24, 2026 People with spinal cord injuries often lose movement even though their brains still send the right signals. Researchers tested whether EEG brain scans could capture those signals and reroute them to spinal stimulators. The system can detect when a ...
Jan. 24, 2026 A large, decades-long study suggests that signs of ADHD in childhood may have consequences that extend well beyond school and behavior. Researchers followed nearly 11,000 people from childhood into midlife and found that those with strong ADHD ...
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Jan. 23, 2026 Chemotherapy’s gut damage turns out to have a surprising upside. By changing nutrient availability in the intestine, it alters gut bacteria and increases levels of a microbial molecule that travels ...
Jan. 23, 2026 Alzheimer’s may be driven far more by genetics than previously thought, with one gene playing an outsized role. Researchers found that up to nine in ten cases could be linked to the APOE gene — ...
Jan. 23, 2026 In Guatemala’s Western Highlands, researchers found that the drinking water people trust most may actually be the riskiest. Bottled water from refillable jugs—seen as the safest choice—was ...
Jan. 23, 2026 New research suggests that auditory hallucinations in schizophrenia may come from a brain glitch that confuses inner thoughts for external voices. Normally, the brain predicts the sound of its own ...
Jan. 22, 2026 Researchers have identified a promising new weapon against triple-negative breast cancer, one of the most aggressive forms of the disease. An experimental antibody targets a protein that fuels tumor ...
Jan. 22, 2026 Type 2 diabetes becomes more dangerous to the heart the longer a person has it. Researchers found that after several years, red blood cells can begin interfering with healthy blood vessel function. ...
Jan. 22, 2026 A new blood test may reveal Crohn’s disease years before symptoms begin. The test detects an unusual immune response to gut bacteria in people who later develop the condition. By studying healthy ...
Jan. 22, 2026 A new study reveals that super agers over 80 have a distinct genetic edge. They are much less likely to carry the gene most associated with Alzheimer’s risk, even when compared with other healthy ...
Jan. 22, 2026 Scientists found that nasal cells act as a first line of defense against the common cold, working together to block rhinovirus soon after infection. A fast antiviral response can stop the virus ...
Jan. 22, 2026 Scientists studying genetic data from over a quarter million people have uncovered new clues about what controls how fast the gut moves. They identified multiple DNA regions linked to bowel movement ...