Update: influenza activity--United States, April 2-8, 2006.

During April 2-8, 2006, the number of states reporting widespread influenza activity decreased to 10. Ten states reported regional activity, 15 reported local activity, 14 reported sporadic activity, and one reported no activity. The percentage of specimens testing positive for influenza decreased in the United States. During the preceding 3 weeks (weeks 12-14), the percentage of specimens testing positive for influenza ranged from 26.4% in the South Atlantic region to 12.5% in the Mid-Atlantic region. During this period, regions reporting the highest proportion of isolates as influenza B included the Pacific (62.5%), Mountain (61.8%), and West North Central (61.2%) regions. Other regions reporting more than 30.0% of recent isolates as influenza B include the East North Central, West South Central, and New England regions. The percentage of outpatient visits for influenza-like illness (ILI) during the week ending April 8 was below the national baseline. The percentage of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold for the week ending April 8.