Overall influenza-like illness (ILI) activity underwent a small increase in the United States during week 16 of the 2015-2016 flu season, but Puerto Rico took a significant turn for the worse as activity there rose to the highest possible level, the Centers for Disease Control and Prevention reported Feb. 5.
Puerto Rico, which had been at level 8 on the CDC’s 1-10 scale of flu activity for the previous 3 weeks, jumped up to level 10 for the week ending Jan. 30, 2016. Meanwhile, the main measure for national flu activity, the proportion of outpatient visits for ILI, was 2.2% for the second week in a row, just above the national baseline of 2.1%, the CDC said.
The state with the highest level of flu activity (level 7) for the week was Connecticut, with Arkansas the only other state in the “moderate” range at level 6. States in the “low” range were Florida, Hawaii, Illinois, Maryland, Nevada, New Jersey, and Pennsylvania at level 4 and Georgia, Idaho, Louisiana, Massachusetts, Mississippi, New Mexico, and Virginia at level 3. All told, there were 22 states with activity above level 1, according to data from the CDC’s Outpatient Influenza-like Illness Surveillance Network.
There were two influenza-associated pediatric deaths reported during week 16, although one death actually occurred during the week ending Jan. 16. There have been nine flu-associated pediatric deaths reported so far during the 2015-2016 season.
The hospitalization rate for the season so far is 2.6/100,000 population, up from 2.1/100,000 last week. Adults aged 65 years and older had the highest rate at 8.5/100,000, with children aged 0-4 years next at 3.8/100,000.