California and 43 other states have reported widespread flu activity, the predominant bug being the Type A H3N2 strain that tends to produce more serious illnesses. Health officials said Friday this year's vaccine is not a good match for more than half of the circulating viruses, including Type A H3N2. But they say it is still advisable to get immunized though the vaccine is not a perfect match as it may help build immunity and enable a faster recovery when people do get ill. Forty-four children in the state have been treated in hospital intensive care units for the flu.