State health officials said yesterday that four Massachusetts children have died of the flu this month.

The Department of Public Health reports that a 12-year-old girl from Worcester County died Sunday from complications of flu, two days after a 15-year-old died of bacterial flu- related pneumonia. These two recent deaths, however, were healthy children before coming down with the flu. The first two influenza deaths happened in a 6-year-old and a 14-year who had significant underlying medical problems.

None of the children was identified because of patient confidentiality laws.

"This has been a very difficult season," Dr. Alfred DeMaria, the state's director of communicable disease control, said yesterday. "The more flu you have, the more likely you are to see these relatively rare instances of complications."

State health officials added that flu cases in Massachusetts peaked in mid-February, although reports of flu activity are expected to go on into April.

Dr. Joanne Cox, medical director of Children's Hospital Primary Care Center recommended that if a child who have fever is healthy, still eats, drinks and is out of bed, parents can wait up to two days before visiting a doctor.

"Your child who just looks like they feel horrible and they have a cough and a high fever, they're the ones who should be seen sooner rather than later," Cox added.