Measles (also called Rubeola) is a highly contagious respiratory infection caused by the measles virus, which infects the nose and throat mucus. The measles virus is part of the paramyxovirus family. First identified in the 9th century, in 1957 Francis Home is credited with determining that measles was caused by an infectious agent.
The infection is primarily spread through coughing and sneezing, which can produce small droplets that can stay suspended in the air for up to two hours or active on surfaces for up to 2 hours as well. People who breathe in these infected droplets and have no resistance to measles can develop the disease. As measles is considered one of the most highly contagious of diseases, exposure to even small amounts of the virus in a brief amount of time can result in transmission. Measles is so contagious that if one person has it, 90% of the people close to that person who are not immune will also become infected.
The virus may also be transmitted through hand and surface contact with secretions and then touching one’s eyes, nose, or mouth. Once infected, the virus attaches itself to the lining of the nose/throat. Despite the availability of a vaccine, measles occurs worldwide with the majority of the cases being people that are not immunized. Measles appears to be only a human disease. There are no known animal or insect sources.