State health officials have declared the measles outbreak in Kansas over.

It's been six weeks since the last measles case was reported, according to the Kansas Department of Health and Environment. That's two incubation periods. Measles can be spread to others from four days before to four days after the rash appears.

The measles affected 14 people in Sedgwick and Johnson counties, in what's been called the worst measles outbreak in 20 years. The measles have been rare in the United States since the creation of the MMR (measles, mumps, rubella) vaccine. More than 590 cases have been confirmed in 21 states from January 1, 2014 through Aug. 18.

Symptoms of measles include fever, blotchy rash on the skin, which spreads from the head to the trunk then to the lower extremities, cough, runny nose, red, watery eyes, feeling run down, achy and tiny white spots with bluish-white centers found inside the mouth.