(INDIANAPOLIS) -- A person who visited the Super Bowl village in downtown Indianapolis last Friday was infected with measles, according to Indiana health officials, who also confirmed a second case of the highly infectious virus.
Health officials learned of two additional probable cases in the state, according to Indiana State Health Commissioner Dr. Gregory Larkin, who added that health departments around the country have been alerted to be aware of the possible spread of the disease.
On Friday, about 200,000 people visited the Super Bowl village, a festival for Super Bowl fans to buy memorabilia, eat and play games, according to the Super Bowl host committee.
Neither of the patients with confirmed cases of measles reportedly attended the game Sunday.
While health officials said they were not yet bracing for a widespread outbreak, they wanted to make the public aware of the recent cases so that if any new infections emerge, they will be quickly identified, treated and confined.
"Even though measles has been declared eliminated in the U.S., it circulates globally, and when we get an importation or somebody gets it while traveling, there is potential for cases to spread," said Dr. Greg Wallace, who heads the Centers for Disease Control and Prevention's Division of Viral Diseases. "The vast majority of measles cases we see are in people who are unvaccinated."
Measles cases in the U.S. have increased. The country saw its highest number of cases in 15 years in 2011, when 220 Americans contracted the illness.
While those who have been vaccinated for the virus will likely remain unaffected, experts said babies younger than 1, pregnant women and anyone with a compromised immune system who attended the event should seek medical care as a precaution.
Measles spreads easily through coughing and sneezing. Symptoms, which include cough, fever, sore throat and a tell-tale rash, begin about eight to 12 days after exposure to the virus. About 30 percent of people who contract measles experience complications, including bronchitis, ear infection, permanent hearing loss, pneumonia and even death.
There is no treatment once measles is contracted, but the vaccine is 95- to 99-percent effective in preventing the illness, said Wallace. Those who are not vaccinated are at high risk of developing the disease, but Americans born before 1957 are often considered immune to measles because it once ran so rampantly throughout the country. Most are likely to have already had the viral infection, according to the CDC.
The measles vaccine may prevent infection when given within 72 hours of exposure, according to experts, so anyone unvaccinated who fears they have been exposed should seek medical advice as soon as possible.
"There's no way for us to possibly track down and contact everybody who may have been at a big public event like this, so we're hoping media alerts will heighten awareness," said Wallace. "At the very least, this is a good opportunity to remind people to make sure they are up to date on their immunizations and remind parents to get their children vaccinated."
States are required to report all measles cases to the Centers for Disease Control and Prevention.
Little information has been made public about the measles cases in Indiana, such as where and when they might have contracted the virus.
Copyright 2012 ABC News Radio