More US families are getting measles shots for their children earlier than the usual schedule as the country's measles outbreak grows, The Guardian and AP report.

The Guardian says the US has twice as many confirmed measles cases as last year. AP calls it the nation's worst measles outbreak in 35 years. Pennsylvania has the most cases, more than 1,350 this year, with over a third in Lancaster County, AP reports, citing state figures. The state has recorded five measles-linked deaths, the outlet reports.

The Centers for Disease Control and Prevention usually advises the first measles, mumps and rubella shot after age 1 and the second between 4 and 6, The Guardian reports. The second dose can be given as soon as four weeks after the first, and Germany, the UK and France recommend earlier timing, the outlet reports. The CDC advises a first shot as early as 6 months in outbreak areas, The Guardian reports.

"There's no reason to wait, measles is here now," Seattle physician Elias Kass said, The Guardian reports. In Lancaster County, clinics run by the nonprofit Union Community Care are vaccinating infants earlier than usual, as experts advise in outbreak areas, AP reports. "It's scary," one parent said, AP reports. "It's spreading quick."

AP says many Amish and conservative Mennonite families, who are less likely to be vaccinated, are showing new openness to the shots, though others still refuse them. Most measles cases are mild, but the disease can cause pneumonia and brain swelling, AP reports.

What we know: Measles is spreading, and more parents are choosing earlier shots for their children.
What we don't: Whether federal health officials will change the standard vaccine schedule.