Measles in the Americas: Going, going — gone! | Science News for Students

Measles in the Americas: Going, going — gone!

Some cases will still emerge as travelers bring the virus home from abroad
Sep 28, 2016 — 12:00 pm EST
Measles baby

This small child bears the red spots that signal a measles infection.

Dave Haygarth/ Flickr (CC BY 2.0)

In the 1950s and ‘60s, measles was a common childhood disease. It plagued kids throughout the world. But that’s no longer true in the Americas. International health officials have just reported that the disease had been wiped out from this wide swath of the Western Hemisphere. It’s no longer circulating from Canada to Chile — and the rest of the Americas in between.

It’s an amazing achievement. But it wasn’t easy.

Consider what life was like in the 1950s. Elementary-school classrooms could be partially emptied every few years as a wave of the disease swept through their community. Each year, back then, the illness sickened an estimated 3 million to 4 million people in the United States alone — mostly young children. Nearly 50,000 of them were so ill they ended up in the hospital. Some 400 to 500 people would die.

All of that changed when a vaccine came along. It allowed doctors to prevent the illness. But it only worked if most people agreed to get immunized. And eventually, most did. It’s taken a half-century, but that campaign against the disease worked — at least in the Americas.

That region has become the first anywhere to have eliminated the viral disease. The Pan American Health Organization (PAHO) and World Health Organization made the long-awaited announcement on September 27.

This does not mean the disease is gone for good. So far, only smallpox has been truly eradicated — erased from the wild.

Measles outbreaks still crop up now and then in the Americas. This year, for instance, 54 people in the United States became infected. They picked up the virus from travelers who brought it home from other parts of the world. The good news: A home-grown emergence in the Americas has not occurred since a 2002 outbreak in Venezuela.

Because measles still circulates widely outside of the Americas, vaccinations remain important. “Our work on this front is not yet done,” says PAHO director Carissa Etienne. “We cannot become complacent with this achievement but must rather protect it carefully.”

Measles: Herd immunity and maternal immunity from Matt ferrari on Vimeo.

Power Words

(for more about Power Words, click here)

complacent     To be smug or uncritical about one's skills or achievements, or to be unduly assured that some pleasant conditions will continue on unchanged. 

measles     A highly contagious disease, typically striking children. Symptoms include a characteristic rash across the body, headaches, runny nose, and coughing. Some people also develop pinkeye, a swelling of the brain (which can cause brain damage) and pneumonia. Both of the latter two complications can lead to death. Fortunately, since the middle 1960s there has been a vaccine to dramatically cut the risk of infection.

outbreak     The sudden emergence of disease in a population of people or animals. The term may also be applied to the sudden emergence of devastating natural phenomena, such as earthquakes or tornadoes.

vaccine     A biological mixture that resembles a disease-causing agent. It is given to help the body create immunity to a particular disease. The injections used to administer most vaccines are known as vaccinations.

virus     Tiny infectious particles consisting of RNA or DNA surrounded by protein. Viruses can reproduce only by injecting their genetic material into the cells of living creatures. Although scientists frequently refer to viruses as live or dead, in fact no virus is truly alive. It doesn’t eat like animals do, or make its own food the way plants do. It must hijack the cellular machinery of a living cell in order to survive.

World Health Organization     An agency of the United Nations, established in 1948, to promote health and to control communicable diseases. It is based in Geneva, Switzerland. The United Nations relies on the WHO for providing international leadership on global health matters. This organization also helps shape the research agenda for health issues and sets standards for pollutants and other things that could pose a risk to health. WHO also regularly reviews data to set policies for maintaining health and a healthy environment.


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Formal Online Announcement: World Health Organization and Pan American Health Organization.​​Region of the Americas is declared free of measles. September 27, 2016.

Further Reading

American Red Cross et al. Measles & Rubella Initiative.