A Phoenix area school district sent parents letters and e-mails, warning them that a pair of children contracted "pertussis."
Both cases were found at Liberty Elementary school in the Paradise Valley Unified School System.
"They wrote down, 'pertussis,' and put it on the door," Darren Gray said. "I had to look it up."
Gray was picking up his six-year-old son from the summer camp, when he noticed a sign on the front door.
"There have been 2 reported cases of Pertussis," the sign reads.
The sign instructs parents to contact the Maricopa County Department of Public Health for more information.
"It's whooping cough," Gray said. "It's highly contagious."
The Department of Health confirmed two cases of the disease in the summer camp at Liberty Elementary, but doctors say parents shouldn't be concerned if their children are vaccinated.
Most people are vaccinated but newborn children are not, and the disease can be deadly to infants.
"I have a two-week-old daughter," Gray explained. "I'm concerned for her."
Gray's six-year-old son is vaccinated but health officials say under rare circumstances, even those vaccinated can carry the disease, and possibly spread it to those without vaccinations, including parents.
In fact, the Department of Public Health urges parents to check-in with their doctors and get booster shots, since the original vaccination can wear off over time.
Other parents are taking the opportunity to remind their children of healthy habits.
"I'm not pulling [my six-year-old son] out," Jeff Wolfe said. "I did pull him aside and tell him to make sure he's washing his hands more."
Health officials say they see several cases of pertussis every year in the valley, and parents should not be concerned if they and their children have been vaccinated.
Gray however, is playing it safe with a newborn occupying the same home as his son.
"There's nothing I can do for a newborn but wait." He says, "and hope nothing happens."
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