With the number of swine flu cases rising, New Haven officials are using advertisements to inform the public.

At a press conference Friday, city officials unveiled a plan to inform residents about basic hygienic measures and the availability of swine flu vaccines. The city will use bus billboards, public service announcements, and the city’s Web site to let residents know as more vaccines reach New Haven from the state government.

The city has received 13,000 doses of swine flu vaccine out of 20,000 it requested from the state government. Because of the shortage, the priorities for vaccination are emergency care providers such as paramedics, day care workers and families with children younger than six months old, Mayor John DeStefano Jr. said Friday. After these groups are vaccinated, pregnant women and children between the ages of two and five will be inoculated, he added.

To keep residents informed about swine flu, the city has placed advertisements on 20 buses. The ads will include a telephone number that people can call to find out where vaccines are available, said Chisara Asomugha, the city’s community services administrator. People can also go to the city’s Web site to find the latest information on swine flu, Asomugha said.

The city will also run public service announcements on television for five weeks, Asomugha added.

School officials are also working to prevent the spread of swine flu, said Will Clark, chief operating officer of the New Haven Board of Education. Since the spring, school administrators have been advising students on proper techniques of coughing and hand-washing. At the press conference, which was held in the Barnard Environmental Magnet School, Hope Flannigan’s first grade class, dressed for Halloween, coughed into their elbows and air-washed their hands to demonstrate.

In addition to putting up posters, the New Haven Health Department installed 400 hand sanitizer terminals over the summer near the entrances to school cafeterias, Clark said.

School officials are encouraging parents to keep students that have flu-like symptoms home from school. By keeping swine flu contained, Clark said, the school board should not have to close any schools because of H1N1. So far, Clark said, school attendance rates have held steady, with a 90 percent attendance rate as of Oct. 29.

“We monitor the rate daily with the help of the Health Department and have our 14 school-based health clinics trained to treat students and take appropriate steps if necessary.”

If more supplies arrive, school officials said they hope to immunize more children. Information was sent home last week about the immunization efforts that are taking place, Clark said, and there will be more updates in the future.

Connecticut has received 178,000 doses of the swine flu vaccine, which have been distributed to health providers across the state.