Measles

Measles is a highly contagious viral infection, which prior to the introduction of effective vaccines was a common experience of childhood, sometimes with fatal consequences. Unfortunately, even today not all children receive the vaccine despite its efficacy and availability. In May 2003, the World Health Assembly endorsed resolution WHA56.20 urging Member countries to achieve a goal to reduce global measles deaths by half by end of 2005 compared with the 1999 estimates. Based on results from surveillance data and a natural history model, overall, global measles mortality decreased 48% from an estimated 871,000 deaths in 1999 to an estimated 454,000 deaths in 2004. Many of the recommended World Health Organization (WHO) measles control strategies now in place had been developed and first used during the early 1990s in the Americas, when the countries of the Caribbean and Latin America adopted a multi-tiered vaccination approach combining routine vaccination and mass vaccination campaigns.

Among the WHO regions, the Region of the Americas has had the most success in controlling measles. Starting in 1999, countries throughout the Region of the Americas embarked on accelerated measles elimination activities, using strategies building on the accomplishments of the polio elimination program. Implementing a measles elimination program was clearly an ambitious task, requiring the collaboration of ministries of health, the private sector, nongovernmental organizations, and multilateral and bilateral international partners. The last occurrence of widespread measles virus transmission in the Americas dates to November 2002. Sporadic cases and outbreaks have continued to occur, although 51% of the 370 measles cases reported in the Americas between January 2003 and April 2006 were positively linked to an importation.