Influenza B Cases Continue to Rise in the United States

Winter is over but the same cannot be said for the 2016-2017 flu season, with the Centers for Disease Control and Prevention (CDC) expecting significant flu activity to continue in the coming weeks.

After five consecutive weeks of decreasing activity, CDC surveillance reports have noted that 36 states are still experiencing widespread flu activity. While the predominant strain of the virus continues to be influenza A (H3N2), a late season uptick in cases of influenza B infections and a decline in influenza A is helping extend the flu season into the spring months.

According to the most recent FluView report, of the flu-positive respiratory specimens collected around the country, about 53% were positive for influenza A and nearly 47% positive for influenza B for the week ending March 18, 2017. In the previous week, 61% of specimens were positive for influenza A while 39% were positive for influenza B. So far this flu season, influenza A has accounted for more than 79% of all flu-positive respiratory specimens.

Overall the percentage of respiratory specimens that tested positive for flu has declined to 18.3% from the previous week’s rate of 18.6%, though there are indicators that the virus continues to impact many parts of the country. Although nine state are now reporting low influenza-like illness (ILI) activity and 23 states are experiencing minimal ILI activity, Alabama, Georgia, Indiana, Kansas, Kentucky, Louisiana, Maryland, Minnesota, Mississippi, Oklahoma, South Carolina, and Virginia are still reporting high ILI activity.

In Alabama, state law makers recently introduced new legislation in the state senate that would require schools to provide parents with information on the flu vaccine. The new measure comes as high flu activity continues in the state during a flu season that has seen high numbers of ill students, prompting school closures. Under the new proposed bill, Alabama school officials would be required to offer information to parents about flu symptoms and virus transmission, along with information about flu vaccination, CDC immunization recommendations, and other infectious diseases.

The Oklahoma State Department of Health has reported four new flu-related deaths in its most recent week of surveillance, bringing the state’s total to 68 deaths so far this flu season. Tulsa County has experienced the highest number of influenza-related deaths in the state with a total of 18, while Oklahoma county has seen eight deaths. The majority of those deaths (47) this season occurred in adults age 65 and older. Of the four new deaths reported in the state, one was a child under the age of 4 in Cherokee County. As a result of the steady flu activity, health officials are still offering flu vaccination to anyone age 6 months or older.

In related news, a new study by researchers at the Perelman School of Medicine at the University of Pennsylvania suggests that doctors may be able to increase the rate of flu vaccination among patients by using a technique called “active choice”. In their paper, published in the Journal of General Internal Medicine, researchers found that by notifying patients of their eligibility for the flu vaccine and prompting them to accept or decline a vaccination order, health care providers showed a 6% increase over clinics that did not use the alert system, and a 37% relative increase in vaccinations from the prior year.

“Our results indicate that this simple intervention could be an effective and scalable approach to use the design of electronic health records to increase the rate of flu vaccinations, which are estimated to prevent millions of flu cases and tens of thousands of related hospitalizations every year,” said study lead author Mitesh S. Patel, MD, MBA, MS in a recent press release. By changing the way these choices are framed, the researchers hope they can help change patient behavior and improve public health.