ATLANTA, April 5 (UPI) -- U.S. seasonal influenza activity remains on the decline, but pockets of cases persist with influenza B accounting for 75 percent of them, officials say.
The weekly flu report of the Centers for Disease Control and Prevention in Atlanta said for the week ending March 30, the proportion of people seeing their healthcare provider for influenza-like illness decreased once again and remained below the national baseline for the second consecutive week.
Baseline influenza activity is the level influenza activity remains throughout the summer and the rest of the seasons. Usually, there is a six- to 12-week period in winter when influenza activity rises above the baseline threshold -- flu season.
Illinois, Michigan, Nevada, New Jersey, South Carolina, Vermont and Virginia, as well as New York City, experienced low influenza-like activity, while 43 states experienced minimal influenza-like illness activity.
The proportion of deaths attributed to pneumonia and influenza based on the 122 Cities Mortality Reporting System decreased to 7.4 percent this week and fell slightly below the epidemic threshold for the first time since the week ending Dec. 29.
One influenza-related pediatric death was reported for a seasonal total of 111 deaths. Thirty-four pediatric deaths were reported during the 2011-12 flu season, 122 in the 2010-11 flu season and 282 during the H1N1 2009-10 flu season.
Widespread influenza activity -- more than 50 percent of a state reporting flu activity -- was reported by Connecticut, Massachusetts, New York and North Carolina.
Seven states reported regional influenza activity: Maine, Nevada, New Hampshire, New Jersey, Ohio, Pennsylvania and Virginia.
Twenty-six states reported local influenza activity and 12 states reported sporadic influenza activity.