The CDC fears that because measles is so prevalent overseas, people who travel are bringing the virus back to U.S. shores. Almost all of the 175 cases of measles reported thus far in 2013 were linked to people who had contracted the disease after traveling outside the country.
"A measles outbreak anywhere is a risk everywhere," CDC director Dr. Tom Frieden said in a press release. "The steady arrival of measles in the United States is a constant reminder that deadly diseases are testing our health security every day. Someday, it won't be only measles at the international arrival gate; so, detecting diseases before they arrive is a wise investment in U.S. health security."
Measles is a respiratory viral illness that grows in the cells that line the back of the throat or lungs. It can cause a fever, runny nose, cough and a rash all over the body. It can lead to ear infections in 10 percent of cases in kids, and 5 percent will develop pneumonia.
Other complications include encephalitis and death. About 18 children every hour around the world die due to measles, the CDC reported. There were 158,000 measles deaths across the globe in 2011 alone.
A new research paper published in JAMA Pediatrics on Dec. 5 shows that measles was "eliminated" in the U.S. from 2000 through at least through 2011. For a disease to be eliminated, there must be no continuous disease transmission for more than 12 months.
However, in 2013, there at least 175 cases and counting -- significantly more than the typical 60 who contract the disease each year.
The new report was released on the 50th anniversary of the measles vaccine. The CDC also published the latest figures on the global progress against measles in its journal Morbidity and Mortality Weekly Report.
Dr. William Schaffner, an infectious disease expert at Vanderbilt University School of Medicine in Nashville, told USA Today that people might be surprised to learn that popular travel destinations in Europe are often where people contract measles.
The CDC added that doctors should consider a person has contracted measles if they are displaying high fever and rashes "especially when associated with international travel or international visitors," and report the cases to their local health department.
Before the measles vaccination program was started in the U.S. in 1963, almost every child was infected by the disease, the CDC said. About 450 to 500 people died from it each year, 48,000 were hospitalized, 7,000 had seizures, and around 1,000 suffered permanent brain damage or deafness before the vaccine was distributed regularly.
About 2.6 million deaths worldwide were attributed to measles until vaccination was available around the globe in the 1980s, the report's authors noted.
The CDC has and continues to push for more vaccinations against measles, especially because the virus is so contagious that the majority of people have to receive protection to prevent an outbreak. The CDC has vaccinated 1.1. billion children globally since 2001 against the disease. They estimate they have prevented 10 million deaths, about one-fifth of all the deaths prevented by modern treatments.
"This is an eminently controllable, eminently eliminatable childhood viral infection," said Schaffner.
But, increasing anti-vaccination beliefs may also be behind growing measles rates in the States. A recent CDC study showed that 82 percent of people who had contracted measles as of September 2013 were not vaccinated, and 9 percent were not sure if they had been vaccinated.
Only one out of five countries have the ability to quickly detect, respond to or prevent global health threats started by infectious diseases, the CDC said. Because people are so mobile, a disease can spread globally in just 24 hours, Frieden pointed out.
"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," he said.
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