Global efforts to immunize more children against measles have saved more than 17 million lives since 2000, according to data just released by the World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention (CDC).

Measles is one of the most contagious diseases ever known. A sick person will infect 90 percent of the unimmunized people with whom he or she comes into contact.

Though it only rarely kills, children are especially vulnerable.

Measles

In 2001, WHO, the CDC, the American Red Cross, the United Nations Foundation, and UNICEF launched the Measles & Rubella Initiative. The goal of the program was to cut deaths by 95 percent by 2015 and to eliminate measles altogether in five of six global regions by 2020.

Since 2000, annual deaths from measles dropped from almost 550,000 to slightly more than 110,000 last year. Total cases dropped from 146 per million people to just 40 during the same period.

WHO officials credited massive vaccination campaigns in the Democratic Republic of the Congo and Nigeria for decreases in reported measles cases in Africa. Cases there fell from more than 170,000 in 2013 to under 75,000 in 2014.

Cases also fell in Southeast Asia.

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Progress Stalled

But the news isn’t all good.

Far more children get the first dose of the vaccine than get the second dose needed to ensure immunity. Only half of the world’s children get the recommended second dose.

The number of children who got one or both doses had been rising, but progress “stagnated” in the past few years, the WHO said.

In the first 10 years of the new century, the global reach of the vaccine increased by 13 percent. But since then, it has remained unchanged.

The numbers suggest that the plan to eradicate measles is in jeopardy. Last year there were outbreaks in China, India, the Philippines, Vietnam, Somalia, Ethiopia, and the Russian Federation.

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What’s the Holdup?

Karen Mah, a spokesperson for UNICEF’s Measles & Rubella Initiative, pointed to a few stubborn problems that have slowed the march of the measles, mumps, rubella, or MMR vaccine.

She noted that in countries with “fragile health systems, reaching children with two doses of measles vaccine is incredibly challenging,” Mah said.

In other countries, such as Ethiopia, India, China, and Nigeria, the sheer number of children poses a challenge.

Recent years have seen major conflicts with historic numbers of refugees. But these haven’t played as much of a role as one might think.

For instance, the eastern Mediterranean and European regions saw decreases in measles illnesses last year.

Conflicts and the refugee camps they create set the stage for infectious diseases to spread. But camps also give aid groups an opportunity to vaccinate a lot of people in one place.

“When these crises occur, UNICEF and other aid agencies quickly move in to provide measles vaccination to decrease transmission and complications or death because these refugee camp conditions are so conducive to spreading measles,” Mah said.

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