In an official announcement from the Pan American Health Organization/World Health Organization (PAHO/WHO), the Americas (South America and North America) were declared as the first region to have eliminated measles. This is the fifth vaccine-preventable disease to have been eliminated in the region. The others are smallpox, poliomyelitis, rubella and congenital rubella. The U.S. now can use the label “eliminated” but that does not mean there will never be a case of measles in this country again.
Measles is a highly contagious disease that is transferred via airborne droplets or by sneezing and coughing. Symptoms include high fever, a severe rash, stuffy nose and reddened eyes. Complications with the infection can lead to death. However, any case of measles would be travel-related, unlike smallpox which currently is eliminated everywhere in the world and only exists in laboratories.
The first response is the body’s reaction to a vaccine. The second is when the body encounters the actual pathogen. You can see that the second response is now much more powerful.
Before widespread vaccination, measles killed 2.6 million people around the world annually. The WHO reports that in 2014 approximately 114,900 people died from measles globally. Most of these people were under the age of five. To put that into perspective, this is equivalent to 13 deaths every hour for a year, and that is a significant decrease from the number of deaths before immunization projects began. Immunization activities have prevented approximately 17 million deaths globally.
Professor of biology Dr. Jonathan Micancin explained how vaccines work: “They trigger an immune response where the cells have two different modes of attack… most of the cells become cells that are directly involved in the attack of that specific antigen (foreign substance that causes an immune response from the body), but some of the cells formed are memory cell. We have a bunch of these go into a ‘wait and see’ status throughout the body, particularly in lymphatic tissue. They are waiting for another exposure and then they can very quickly reproduce the immune response to the pathogen.”
Not every person is vaccinated against the disease, and there is something of an anti-vaccination trend that began with a false study from 1997 suggesting that vaccines cause autism. Publichealth.org reveals that this study was retracted due to severe ethical, financial and procedural errors and the author lost his medical license. As certain diseases become less common publichealth.org suggests that people develop the mindset that they no longer need to vaccinate against those diseases. Vaccination does need to continue in order to create a herd immunity.
The fight against measles in the Americas is successful because of herd immunity which occurs when a significant percentage of the population has been vaccinated against a disease. Since so many people are immune, the disease becomes weaker and cannot transfer from person to person. When the disease is weakened enough that people are no longer getting it, then herd immunity has successfully protected those who are not vaccinated. This is an important type of immunity because it can protect people who may be medically incapable of receiving their own vaccines.