Arizona health officials are on high alert for measles ahead of the Super Bowl. As thousands head to the big game, the state is trying to keep track of 1,000 people who may have been exposed to the virus.
"A lot of people don't realize measles is the most contagious infectious viruses that we know of," CBS News medical contributor Dr. Holly Phillips said Friday on "CBS This Morning. "Not only can people cough and sneeze it on you, it lingers in air for up to two hours, it lives on surfaces for up to two hours, so you can be exposed and not even realize it."
Transmission at the Super Bowl is particularly concerning because there is a 90 percent transmission rate for anyone who come in closes contact with infected persons. Health officials want any unvaccinated person exposed to measles to stay home for three weeks.
Measles is also sparking worry because the virus is initially difficult to detect.
"There's an up to a 21-day incubation period without symptoms and in the first three or four days of symptoms, it's hard to distinguish from the cold or flu," Phillips said. "It's not until you get the white spots in your mouth and that reddish-brown rash that spreads down your body until you can really recognize it."
There are at least 98 cases in 14 states, many connected to an outbreak at Disneyland. Health officials suspect a visitor from overseas may be to blame.
"Most people in this outbreak were not vaccinated or just had no idea whether or not they were," Phillips said. "If you're not sure if you've been vaccinated, you can go to your doctor. You can have a quick blood test that will say whether or not you're immune."
Phillips said for those not immune, a two vaccine protocol will be administered and if anyone who is slightly immune can receive a booster shot. People born before 1957 are likely immune but should be tested to be sure.