More than 98 percent of measles patients were unvaccinated, despite the U.S. maintaining a high vaccination rate. Nearly all 175 cases were linked to people who brought the infection home from abroad. The U.S. usually gets around 60 such "imported" cases per year.
According to the CDC, the country's safety net has become porous as more people decline vaccination.
Measles has been officially eliminated in the U.S. from 2000 through 2011. Elimination means the continuous absence of the disease for 12 months.
Doctors recommend that with this influx of measles cases from overseas, increased caution should be exercised when children exhibit a high fever and rash.
Before the vaccination against measles began in 1963, nearly all children became infected and 450 to 500 people died each year.
“There may be a misconception that infectious diseases are over in the industrialized world. But in fact, infectious diseases continue to be, and will always be, with us. Global health and protecting our country go hand in hand,” Dr. Frieden said.