BOSTON -- Two Boston schools were closed Tuesday for seven days because of influenza-like illnesses.

Superintendent Carol R. Johnson said that the John D. O’Bryant School of Mathematics and Science in Roxbury and the James Condon Elementary School in South Boston will close Wednesday and reopen on Wednesday, June 3.

Johnson made the decision to close the schools temporarily in consultation with the Boston Public Health Commission and Mayor Thomas M. Menino. Officials said they hope that the temporary closures will prevent new infections and avoid unnecessary illness.

With this announcement, a total of five Boston Public Schools have been closed because of influenza concerns, including Boston Latin School in the Fenway (reopening tomorrow, Wednesday, May 27), the Umana Middle School Academy in East Boston (reopening Thursday, May 28), and the Frederick Middle School in Dorchester (reopening Friday, May 29). Other public and private schools around the state also have been closed recently.

"With significant numbers of students out sick with flu-like symptoms, we have decided to close these buildings for the next seven days in order to prevent new infections," Johnson said.

The O’Bryant serves more than 1,200 students in grades 7-12. The Condon serves nearly 700 students in kindergarten through grade 5. Both schools reported unusually high absenteeism rates Tuesday, as well as many student leaving school sick, and follow-up calls to families confirmed that many of the students are exhibiting flu-like symptoms.

At each school, there are two confirmed cases of the H1N1 virus. Officials from the Boston Public Health Commission and Boston Public Schools concluded that having so many students sick not only impedes the learning environment but also makes it easier to transmit infection. Therefore, the decision was made to close the schools for seven days, after which time most types of flu are no longer contagious.

Meanwhile, public health officials confirmed 66 new cases of H1N1 flu on Tuesday, bringing the total in the state to 350. Seven of the newly confirmed cases were hospitalized. The total number of hospitalizations is 27.

Officials said flu outbreaks evolve in unpredictable ways. It is impossible to know whether the outbreak will decrease, remain the same or grow in coming weeks, and whether the illness will remain at its current severity, which, on the whole has been relatively mild.

Some severe cases may occur in people with underlying risk factors such as young children, the elderly, and people with chronic medical conditions. The Centers for Disease Control and Prevention and DPH are watching closely for signs of increased severity of the H1N1 influenza, and will continue to monitor and report on any developing trends.

Because there is no vaccine for H1N1 influenza, public health officials remind all Massachusetts residents to continue taking simple steps to keep themselves and others healthy.

Wash your hands frequently with soap and warm water or use an alcohol-based hand sanitizer.

Cover your cough with a tissue or cough into your inner elbow and not into your hands.

If you are sick, stay home from work, and if your child is sick keep them home from school for seven days, or 24 hours after your symptoms go away -- whichever is longer.