Infectious Diseases

Infectious diseases, also known as contagious diseases or transmissible diseases, and include communicable diseases, comprise clinically evident illness (i.e., characteristic medical signs and/or symptoms of disease) resulting from the infection, presence and growth of pathogenic biological agents in an individual host organism. In certain cases, infectious diseases may be asymptomatic for much or all of their course. Infectious pathogens include some viruses, bacteria, fungi, protozoa, multicellular parasites, and aberrant proteins known as prions. These pathogens are the cause of disease epidemics, in the sense that without the pathogen, no infectious epidemic occurs.

Transmission of pathogen can occur in various ways including physical contact, contaminated food, body fluids, objects, airborne inhalation, or through vector organisms. Infectious diseases that are especially infective are sometimes called contagious and can be easily transmitted by contact with an ill person or their secretions. Infectious diseases with more specialized routes of infection, such as vector transmission or sexual transmission, are usually regarded as contagious but do not require medical quarantine of victims.

The term infectivity describes the ability of an organism to enter, survive and multiply in the host, while the infectiousness of a disease indicates the comparative ease with which the disease is transmitted to other hosts. An infection is not synonymous with an infectious disease, as some infections do not cause illness in a host.

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

Latest Spotlight News

Hacking the nervous system

When Maria Vrind, a former gymnast from Volendam in the Netherlands, found that the only way she could put her socks on in the morning was to lie on her back with her feet in the air, she had to accept that ...

Diagnosing cancer with help from bacteria

Engineers at MIT and the University of California at San Diego (UCSD) have devised a new way to detect cancer that has spread to the liver, by enlisting help from probiotics—beneficial bacteria similar to ...

Brain signals contain the code for your next move

Is it possible to tap into the signalling in the brain to figure out where you will go next? Hiroshi Ito, a researcher at the Kavli Institute for Systems Neuroscience at the Norwegian University of Science ...