Search results
Results from the WOW.Com Content Network
The following outline is provided as an overview of and topical guide to concepts related to infectious diseases in humans.. Infection – transmission, entry/invasion after evading/overcoming defense, establishment, and replication of disease-causing microscopic organisms (pathogens) inside a host organism, and the reaction of host tissues to them and to the toxins they produce.
Worldwide, approximately 18% of cancer deaths are related to infectious diseases. [3] This proportion ranges from a high of 25% in Africa to less than 10% in the developed world. [3] Viruses [65] are the usual infectious agents that cause cancer but bacteria and parasites may also play a role. Oncoviruses (viruses that can cause human cancer ...
Bacteria involved in causing and treating cancers. Cancer bacteria are bacteria infectious organisms that are known or suspected to cause cancer. [1] While cancer-associated bacteria have long been considered to be opportunistic (i.e., infecting healthy tissues after cancer has already established itself), there is some evidence that bacteria may be directly carcinogenic.
Such illness responses include lethargy, depression, anxiety, malaise, loss of appetite, [3] [4] sleepiness, [5] hyperalgesia, [6] reduction in grooming [1] [7] and failure to concentrate. [8] Sickness behavior is a motivational state that reorganizes the organism's priorities to cope with infectious pathogens .
Viruses are one of the most important risk factors for cancer development in humans. [2] Infection by some hepatitis viruses, especially hepatitis B and hepatitis C, can induce a long-term viral infection that leads to liver cancer in about 1 in 200 of people infected with hepatitis B each year (more in Asia, fewer in North America), and in ...
An immune response is a physiological reaction which occurs within an organism in the context of inflammation for the purpose of defending against exogenous factors. These include a wide variety of different toxins, viruses, intra- and extracellular bacteria, protozoa, helminths, and fungi which could cause serious problems to the health of the host organism if not cleared from the body.
A human pathogen is a pathogen (microbe or microorganism such as a virus, bacterium, prion, or fungus) that causes disease in humans.. The human physiological defense against common pathogens (such as Pneumocystis) is mainly the responsibility of the immune system with help by some of the body's normal microbiota.
Cancer related to one's occupation is believed to represent between 2–20% of all cases. [17] Most cancer deaths caused by occupational risk factors occur in the developed world. [16] Job stress does not appear to be a significant factor at least in lung, colorectal, breast and prostate cancers. [18]