A number of children on Cape Cod have been diagnosed with whooping cough. These new cases are all being reported in Falmouth. Massachusetts is one of just 18 states that allow a parent to exempt their children from vaccines on philosophical grounds. Data examined by the I-Team showed the number of exemptions has quadrupled over the past 25 years. Public health officials tell WBZ that once those exemption rates start to climb, so does the risk of an outbreak. All of the whooping cough patients in this outbreak, 15 in total, go to Falmouth High School. The I-Team obtained new data from the Public Health Department and found the number of Cape Cod kindergarten students exempted from immunizations is almost five percent and up from last year. Once vaccination rates go down, the likelihood of an outbreak increases and this has happened both in Minnesota and California," says Dr. Sharon Daley, Chief of Pediatrics at Cape Cod Hospital. No one knows for sure why exemption rates are so high on the Cape. But in this case, a school official tells WBZ that all the students had been immunized.