The potential of vaccines was realized when, in late September, the World Health Organization (WHO) and Pan-American Health Organization (PAHO) declared that measles virus has been eliminated from North, Central, and South America.
This declaration marks the first time measles, one of the most highly contagious diseases, has been eliminated from an entire region of the world. Individual countries, such as the United States, have been declared measles-free in the past, but never an entire region.
Elimination means that transmission of the disease within the country has been stopped. However, the virus can still be imported from other parts of the world and can be spread to non-immune individuals in the country and cause outbreaks. Because so many parts of the world continue to have measles transmission, vaccination cannot be stopped. Maintaining high vaccination rates in the region of the Americas is critical to protecting the achievement. According to the WHO, almost 245,000 cases of measles were reported throughout the world during 2015.