Dr. Timothy Jacks is an Arizona pediatrician on the front lines of the measles outbreak that's sweeping the United States, but when he spoke to Congress today, it was personal.

He got a call from the hospital where his 2-year-old daughter Maggie just finished a round of chemotherapy telling him that Maggie and her 10-month-old brother Eli were exposed to measles, he told the Senate Committee on Health, Education, Labor and Pensions, which convened today to discuss the re-emergence of vaccine-preventable diseases.

The chemotherapy rendered Maggie's immune system unable to fight the virus even with the first dose of the MMR vaccine, and Eli is too young to get the vaccine, he said.

"My measles-exposed children have been quarantined at home for nearly two weeks now, and we anxiously watch for signs of disease," Jacks said, explaining that because of Maggie's compromised immune system, she has to go to the emergency room every time she gets a fever. "Every warm forehead, every sign of rash, and every runny nose could be the start of measles, and that brings me back to why I am here."



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So Jacks wrote a letter to the parents in the hospital who didn't vaccinate their children and exposed Maggie and Eli to the measles, and he said the letter has been shared 1.3 million times.

"I assume you love your child just like I love mine," he wrote to those anonymous parents. "I assume that you are trying to make good choices regarding their care. Please realize that your child does not live in a bubble. When your child gets sick, other children are exposed. My children. Why would you knowingly expose anyone to your sick unvaccinated child after recently visiting Disneyland? That was a bone-headed move."







The measles outbreak, which the U.S. Centers for Disease Control and Prevention say is linked to a group of unvaccinated Disneyland visitors, has now spread to 17 states with 121 confirmed cases, the CDC said Monday.

Because of the exposure, both of Jacks' children had to endure a round of painful antibody shots, and the family had to cancel their winter vacation, which had been planned for the only three weeks Maggie wasn't doing chemo, Jacks said. He said he also feared the complications from measles, which can include pneumonia, swelling of the brain and death.

He urged Congress to promote the importance and safety of vaccinations.

"This issue is close to my heart as a father and pediatrician," Jacks concluded. "With your help, we can put an end to vaccine-preventable illnesses and protect the innocent. We can protect our children."