As it was with smallpox, polio, rubella and congenital rubella syndrome, the Americas has become the first region in the world to eliminate measles. The announcement was made this week during the 55th Directing Council of the Pan American Health Organization/World Health Organization (PAHO/WHO), crediting mass vaccination over the last few decades. But while no new cases are originating in the region, officials warned that measles can still be brought in from overseas, meaning vaccination efforts need to be maintained to keep the disease under control.
Measles may not seem too serious a disease to many people: an itchy red rash appears, usually accompanied by a fever and cold-like symptoms, and it's all over in a week or two. That's the case for the vast majority of sufferers, but the disease can lead to severe complications like blindness, swelling of the brain, and even death. Those most at risk are populations in developing countries, young children, pregnant women, and people suffering from malnutrition or weakened immune systems from diseases like HIV/AIDS.
Up until 1980, PAHO reports that worldwide, measles was responsible for 2.6 million deaths each year, with 12,000 of those occurring within the region of the Americas. With the introduction of a low-cost, widely available triple viral vaccine, designed to combat measles, mumps and rubella, the number of worldwide cases has fallen by 95 percent in 35 years. WHO estimates that these efforts saved the lives of 17.1 million people between 2000 and 2014.
"This is a historic day for our region and indeed the world," says PAHO/WHO Director Carissa F. Etienne. "It is proof of the remarkable success that can be achieved when countries work together in solidarity towards a common goal. It is the result of a commitment made more than two decades ago, in 1994, when the countries of the Americas pledged to end measles circulation by the turn of the 21st century."
After that initiative, the United States managed an elimination of endemic, or local, transmission of measles by the year 2000, and by 2002 the rest of North, South and Central America appeared to be free of home-grown cases too. Certification was held off until both measles and rubella could be declared together, but a new outbreak in 2013 delayed things further. After the last endemic case was reported in Brazil in July 2015, the International Expert Committee for Measles and Rubella Elimination reviewed the evidence between then and August 2016, and determined that the elimination criteria had been satisfied.
Elimination does not equal eradication, though, with cases still being introduced into the Americas from foreign travelers. Maintaining vaccination rates can help contain these outbreaks.
"I would like to emphasize that our work on this front is not yet done," says Etienne. "We can not become complacent with this achievement but must rather protect it carefully. Measles still circulates widely in other parts of the world, and so we must be prepared to respond to imported cases. It is critical that we continue to maintain high vaccination coverage rates, and it is crucial that any suspected measles cases be immediately reported to the authorities for rapid follow-up."
The achievement is discussed in the video below.