The Centers for Disease Control (CDC) says approximately 6 million doses of novel H1N1 flu vaccine were shipped throughout the United States as of Oct. 17, but Evanston, like many Illinois municipalities, is waiting for its supply. A delay in the production of the vaccines has pushed back scheduled immunization clinics across the state.

Carl Caneva of the City’s health department said, “The City ordered 50,000 doses. We’ve not received any yet, and there is no set date we can expect them. The Illinois Department of Public Health is doling them out.”

Mr. Caneva said that 40-45 million doses are expected in Illinois, but the date of arrival is still uncertain.

The novel H1N1 virus, formerly called the “swine flu,” spread through St. Athanasius School last week. With 26 percent of the students home with the flu, Mr. Caneva said, school officials decided to close the school on both Friday and Monday. He said the decision was “theirs – not the decision of the Evanston Health Department. It helped prevent the spread of the virus within the school and gave people time to recover.”

The CDC does not have a percentage of absences that would trigger such a decision, Mr. Caneva added.