Measles is one of the most highly contagious diseases, but is preventable through vaccination. The measles virus is spread through coughing and sneezing. Before widespread use of measles vaccines there was an average of half a million measles cases and hundreds of deaths each year in the U.S. Measles is common in many parts of the world, including both industrialized and developing countries. Local cases of measles are often linked to travel or exposure to recent travelers. Worldwide, more than 20 million people are infected each year. Measles is the leading cause of vaccine-preventable death among children in the world.
Resources for the general public
Resources for health care providers
Purpose of surveillance:
- To facilitate prompt diagnostic testing
- To identify cases and exposed persons at risk for transmitting measles to others
- To identify susceptible contacts of cases for post-exposure prophylaxis or preventive treatment
- To implement disease control measures to prevent transmission
No measles cases were reported in King County in 2012. Seven King County residents traveled on airplanes where an infectious measles case was subsequently identified. Investigations were conducted to assure that exposed susceptible persons take appropriate precautions to prevent illness and transmission of infection to others should they develop measles.
In recent years, all measles cases in King County have been imported from other countries. In 2010 a child adopted from India was infected with measles before arriving in the US. Over 100 King County residents were identified as at-risk for exposure to measles, though no secondary cases were reported (likely due to high measles vaccine coverage in the population). Also in 2010, a Canadian resident with infectious measles visited popular public venues in Seattle resulting in public notifications regarding the risk for measles exposure, no subsequent cases were identified.
Individual cases in 2007 and 2009 were acquired while traveling in India. In 2004, a cluster of six cases of measles occurred in toddlers adopted from orphanages in China, with one secondary case in a family member visiting from California. In 2001, 12 cases of measles were reported, all linked to an outbreak in Korea.
Each year in Washington State there are fewer than 10 cases reported.