66 more swine flu cases confirmed in Mass.

By Stephen Smith, Globe Staff

State disease investigators reported this afternoon that 66 more Massachusetts residents have confirmed cases of swine flu and that seven of them required hospitalization.

Since the novel virus that causes the disease arrived in the state a month ago, 350 infections have been confirmed by laboratory testing, and 26 patients have been so ill that they had to be hospitalized for at least one night. More than two-thirds of the cases in Massachusetts have been reported from two Boston-area counties, Middlesex and Suffolk, and three-fourths of confirmed illnesses are in people 20 and younger.

The number of confirmed cases, specialists said, likely reflects only a small fraction of illnesses caused by the H1N1 virus. Many other people, doctors said, have probably experienced bouts of sickness caused by the germ but their symptoms were sufficiently mild that they did not seek medical attention and, thus, were not tested.