Starting in April, North Carolina will require that all children born after April 1, 2001, receive vaccinations against chickenpox before they are 19 months of age. Without the chickenpox vaccine and the nine other required vaccines required by state health officials, children will be unable to enroll in day care centers or public schools. Introduction of the chickenpox vaccine into the state's universal vaccination program was delayed due to funding issues, as the state pays for all childhood shots; the addition of the chickenpox vaccine will cost about $700,000 annually. With more states requiring the chickenpox vaccine for children, Merck--the only manufacturer of the vaccine--is having difficulty meeting demand.