contagions

 What are contagions? Contagions are diseases that are spread by direct contact with an infected person or animal. Other factors such as contact with contaminated inanimate objects or indirect transmission via vectors, for example, mosquitoes, can also facilitate transmission. Contagions that are transmitted by bites from arthropods like mosquitoes and ticks have been associated with a variety of diseases, including the West Nile Virus.

What is the difference between a contagious disease and an infectious disease?

A contagious disease is one that is spread physiologically through direct contact with an infected person or animal; this differs from an infectious disease that spreads through more remote means such as the airborne transmission of germs (e.g., influenza).

What are the vectors of disease? Vectors are bugs or animals that spread diseases. Some common vectors include mosquitoes (malaria, yellow fever), flies and rats (typhus), and ticks (Lyme disease).

What is a reservoir? A reservoir is an environment in which an infectious agent normally lives. For example, mosquitos are reservoirs for malaria.

How does a pathogen move from one person to another? A pathogen can move from one person to another through direct contact with infected people, by shedding virus or bacterial cell contents into the air, by arthropod bites, or indirectly via food and water supplies.

How can you stop the transmission of disease? A number of precautions can be taken to avoid the transmission of contagions. Care must be taken to not touch or come into contact with an infected person. People with contagious diseases must quarantine themselves, i.e., stay away from others until they are no longer contagious. If people must interact with those who are infected, they should wear gloves and protective clothing or masks, and wash their hands frequently. Infected house pets can be quarantined to prevent disease transmission via bites they might make, and infected animals that are killed by hunters should be handled carefully so as to avoid disease transmission through blood or fluids on the hunter's clothes or skin.

Contagious Diseases

Diseases that are spread by direct contact with an infected person or animal are considered contagious. The following is an alphabetical list of some infectious diseases that are caused by viruses: Ebola Virus Disease (EVD), HIV/AIDS, influenza, measles, mumps, rubella, smallpox, West Nile Virus (WNV), and Yellow Fever. Diseases that can be transmitted by contact with contaminated objects are also considered contagious: Anthrax, botulism (food poisoning), brucellosis (undulant fever), and tetanus. Arthropod-borne diseases are also considered contagious because they can spread through bites. Examples include malaria and Lyme disease.

Infectious Diseases

Diseases that are spread through indirect contact with infected agents, rather than direct contact with an infected person or animal are considered infectious. The following is an alphabetical list of some infectious diseases: Anthrax, botulism (food poisoning), brucellosis (undulant fever), cholera, Creutzfeldt-Jakob disease (CJD), Ebola Virus Disease (EVD), HIV/AIDS, Legionnaires' disease, leprosy, malaria, measles, mumps, rubella, smallpox, syphilis, tuberculosis, and yellow fever. There are three types of infectious diseases: Arthropod-borne Diseases, Waterborne Diseases, and Foodborne Diseases.

Arthropod-Borne Diseases

Arthropods such as mosquitoes transmit some infectious diseases. These include several viruses spread by mosquitoes such as: dengue fever, encephalitis A through E, Japanese encephalitis virus (JEV), Kyasanur Forest disease (KFD), St. and West Nile Virus. Note that some of the pathogens that cause the infectious diseases listed above can also cause contagious diseases.