MONTPELIER (AP) - Thousands of Vermont parents could be hearing from medical professionals this week who will be asking about the vaccination histories of their children.
It's part of a study being done by the Centers for Disease Control and Prevention and the Vermont Health Department that is seeking to determine if the whooping cough vaccine isn't as effective against a new strain of the disease.
The researchers are examining the records of 854 people, ages 4 to 19, who contracted whooping cough from late 2011 to early 2013.
They are also examining a control group of about 2,500 people from the same age group and parts of Vermont who did not get sick.
They calls are meant to ensure the study looks at the complete vaccination histories of the people being studied.