ATLANTA, April 25 (UPI) -- For the week ending April 19, overall U.S. flu activity was down except in Texas, the New England, New York and New Jersey where influenza B predominated.
The weekly flu report by the Centers for Disease Control and Prevention in Atlanta said the national proportion of people seeing their healthcare provider for influenza-like illness decreased and remained below the national baseline of 2 percent. Baseline influenza activity is the level that clinical influenza activity remains throughout the summer.
Of the 5,061 specimens tested by U.S. World Health Organization and National Respiratory and Enteric Virus Surveillance System laboratories, 12 percent were positive for influenza a decrease from the previous week.
Influenza B viruses accounted for 56 percent of flu viruses nationally and are causing an increase in influenza-like-illness in parts of the Northeast, the report said.
Texas reported moderate influenza-like illness activity, while New Jersey, Rhode Island, Vermont, Wisconsin and New York City reported low influenza-like illness activity. Forty-four states experienced minimal influenza-like illness activity. Delaware did not have sufficient data to calculate an activity level.
Connecticut, Massachusetts, New Jersey, New York and Rhode Island reported widespread flu activity -- more than half of the state's counties reported flu in the previous week.
Maine, New Hampshire and Oklahoma reported regional activity, while Alaska, Arizona, Delaware, Louisiana, Maryland, New Mexico, Ohio, Pennsylvania, South Carolina, Utah, Vermont, Virginia and Washington reported local flu activity.
Sporadic influenza activity was reported by 25 states and Indiana, Kansas, Mississippi and Tennessee reported no influenza activity.