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

Novel approach to track HIV infection

Northwestern Medicine scientists have developed a novel method of tracking HIV infection, allowing the behavior of individual virions—infectious particles—to be connected to infectivity.

Make way for hemoglobin

Every cell in the body, whether skin or muscle or brain, starts out as a generic cell that acquires its unique characteristics after undergoing a process of specialization. Nowhere is this process more dramatic than it is ...

How whip-like cell appendages promote bodily fluid flow

Researchers at Nagoya University have identified a molecule that enables cell appendages called cilia to beat in a coordinated way to drive the flow of fluid around the brain; this prevents the accumulation of this fluid, ...