Immunology

T cells found to require rest and maintenance

T cells, biology textbooks teach us, are the soldiers of the immune system, constantly on the ready to respond to a variety of threats, from viruses to tumors. However, without rest and maintenance T cells can die and leave ...

HIV & AIDS

Engineered stem cells seek out, kill HIV in living organisms

(Medical Xpress) -- Expanding on previous research providing proof-of-principal that human stem cells can be genetically engineered into HIV-fighting cells, a team of UCLA researchers have now demonstrated that these cells ...

Oncology & Cancer

Scientists find that normal breast cells help kill cancer cells

It is well known that the human body has a highly developed immune system to detect and destroy invading pathogens and tumor cells. Now, researchers at the U.S. Department of Energy's Lawrence Berkeley National Laboratory ...

Health informatics

Biologists train AI to generate medicines and vaccines

Scientists have developed artificial intelligence software that can create proteins that may be useful as vaccines, cancer treatments, or even tools for pulling carbon pollution out of the air.

Medical research

How gut microbes can evolve and become dangerous

Gut microbes have been linked to both good health and the promotion of diseases such as autoimmune disorders, inflammatory bowel diseases, metabolic syndrome, and even neuropsychiatric disorders.

page 1 from 40

Pathogen

A pathogen (from Greek πάθος path "suffering, passion", and γἰγνομαι (γεν-) gignomai (gen-) "I give birth to"), infectious agent, or (more commonly) germ, is a biological agent that causes disease or illness to its host. There are several substrates and pathways whereby pathogens can invade a host; the principal pathways have different episodic time frames, but soil contamination has the longest or most persistent potential for harboring a pathogen.

The body contains many natural defenses against some of the common pathogens (such as Pneumocystis) in the form of the human immune system and by some "helpful" bacteria present in the human body's normal flora. However, if the immune system or "good" bacteria is damaged in any way (such as by chemotherapy, human immunodeficiency virus (HIV), or antibiotics being taken to kill other pathogens), pathogenic bacteria that were being held at bay can proliferate and cause harm to the host. Such cases are called opportunistic infection.

Some pathogens (such as the bacterium Yersinia pestis, which may have caused the Black Plague, the Variola virus, and the Maleria protozoa) have been responsible for massive numbers of casualties and have had numerous effects on afflicted groups. Of particular note in modern times is HIV, which is known to have infected several million humans globally, along with the Influenza virus. 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.

Not all pathogens are negative. In entomology, pathogens are one of the "Three P's" (predators, pathogens, and parasitoids) that serve as natural or introduced biological controls to suppress arthropod pest populations.

This text uses material from Wikipedia, licensed under CC BY-SA