The residents all were exposed at a recent youth conference in Maryland along with over 600 others from around the country. The Warren County patient, whose name and town of residency was not disclosed, is reported to be improving, according to the Missouri Department of Health and Senior Services. The towns of the others who might have been exposed also were not disclosed. Local health department officials were unable to confirm if any of the exposed residents lived in Franklin County. The 24-year-old woman reportedly became ill after returning home. Her family is under voluntary quarantine, said Susan Kneeskern, public health consultant with the department. The health department encourages measles vaccinations for children beginning at age 12-15 months with a second dose usually given before the start of kindergarten. The infected woman was not vaccinated. "The best way to avoid getting the measles is to be immunized," Kneeskern said. "The other 11 folks have taken measures to reduce their risks such as immunization or medications," she said. "Measles is highly contagious. The important message is that anyone with symptoms should be aware and notify their health care provider by telephone," Kneeskern said. "People should stay where they are at," she added. Kneeskern also said the best way people can deal with any communicable disease outbreak is to stay up to date with reputable news sources. Measles, a viral infection of the respiratory system, results in three deaths per 1,000 cases in developed countries, according to The Journal of Infectious Diseases. Fever-like symptoms with a red, blotchy rash may take one to three weeks to appear after a person is infected.