Carnegie Mellon University began administering 2,000 doses of the H1N1 vaccine yesterday, a scene that will be repeated at other city college campuses this week and next.

Penn State University also began administering 1,000 doses of the vaccine on its State College main campus yesterday.

CMU, Penn State, the University of Pittsburgh and Duquesne University all received shipments of the vaccine in nasal spray form Friday. Pitt received 1,400 doses; Duquesne, 2,000; and Penn State, 1,000.

Flu shots are made of killed influenza virus, while the nasal spray, called FluMist, is a live but weakened strain.

The state Department of Health said several factors are used in determining how many doses are sent to providers, including the doses available and the timing of the schools' requests.

Certain groups cannot take the spray vaccine: Children under 2, pregnant women, people with chronic health conditions and others with weakened immune systems.

The U.S. Centers for Disease Control and Prevention said yesterday that injectable vaccine is beginning to ship this week.

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