US flu activity drops further as hospitalizations rise

The Centers for Disease Control and Prevention's (CDC's) weekly FluView update today shows that although flu most likely peaked in mid-February, several indicators remain elevated because of the season's severity.

The percentage of outpatient visits for influenza-like illness (ILI) dropped to 5.0% last week, down from the previous week’s rate of 6.7%. That ILI is now similar to what was seen during the peak of last season, the CDC said in an accompanying summary.

The 2017-18 season has now surpassed a severe 2014-15 season in terms of hospitalizations. According to the CDC, last week's cumulative overall rate of hospitalizations was 81.7 per 100,000 people.

"The overall hospitalization rate and all age-specific hospitalization rates, with the exception of children 5-17 years, are now higher than the end-of-season hospitalization rates for 2014-2015; a high severity, H3N2-predominant season. The hospitalization rate for children 5-17 is similar to that of 2014-2015," the CDC said.

As has been the trend all season, adults 65 and older had the highest rates of hospitalization, 350.7 per 100,000 population, followed by adults aged 50 to 64 (88.5 per 100,000 population) and children aged 0 to 4 years (57.8 per 100,000 population). All of those numbers increased substantially from the previous report.

The vast majority of hospitalizations were associated with influenza A virus (81.6%), and 17.8% were associated with influenza B.

Though this season is still dominated by influenza A, influenza B continues to rise. Of all positive lab samples reported to the CDC last week, 54.2% were influenza A viruses and 45.8% were influenza B. Of the influenza A strains, 19.4% were subtyped H1N1, and 78.8% were H3N2.

Flu is losing traction in some US states. Only 32 states and Puerto Rico now report high flu activity, down from 39 reported in the previous week. Widespread flu was reported in 45 states and Puerto Rico, down from 48 states the week before. 

Pediatric deaths top 100; FDA warns of false remedies

There were 17 pediatric deaths reported in the last week, bringing the total number of pediatric deaths for the season to 114. As flu is likely to keep spreading for several weeks, the CDC still recommends that any children over the age of 6 months who have not done so yet receive a flu shot. Mid-season estimates show the flu shot is more effective for kids than adults.

Finally, today the Food & Drug Administration (FDA) warned that this year's severe flu season has brought with it fraudulent flu remedies, including counterfeit antivirals purchased from fake online pharmacies.

FDA Commissioner Scott Gottlieb, MD, said, "We understand the toll this year's flu season has taken on peoples' lives. As the flu continues to make people sick—and even cause deaths—unscrupulous actors may also be taking advantage of unsuspecting consumers by promoting their fraudulent products that have not been reviewed by the FDA to be safe and effective."

There are no legal over-the-counter medications to reduce the duration of flu symptoms or the severity of illness, the FDA said. Any product claiming to treat or prevent the flu is fraudulent and potentially dangerous.

See also:

Mar 2 CDC FluView

Mar 2 FDA notice

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