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

Study shows epigenetic changes can drive cancer

Cancer has long been thought to be primarily a genetic disease, but in recent decades scientists have come to believe that epigenetic changes – which don't change the DNA sequence but how it is 'read' – also play a role ...

Missing sleep may hurt your memory

Lack of sleep, already considered a public health epidemic, can also lead to errors in memory, finds a new study by researchers at Michigan State University and the University of California, Irvine.

Clearing cells to prevent cervical cancer

A study published online in the International Journal of Cancer earlier this month describes a novel approach to preventing cervical cancer based on findings showing successful reduction in the risk of cervical cancer after ...

FDA approves hard-to-abuse narcotic painkiller

(HealthDay)—A new formulation of a powerful narcotic painkiller that discourages potential abusers from snorting or injecting the drug has been approved by the U.S. Food and Drug Administration.

What sign language teaches us about the brain

The world's leading humanoid robot, ASIMO, has recently learnt sign language. The news of this breakthrough came just as I completed Level 1 of British Sign Language (I dare say it took me longer to master signing ...