Shannon Zwanziger had the flu for a week when she died, her family says.

Shannon Zwanziger had the flu for a week when she died, her family says.

The CDC is reporting that flu has officially crossed the threshold to be considered an epidemic in the United States this year and has caused the deaths of at least 15 children. The number of Flu related deaths this year is higher than last year and the number is increasing. The latest figures, released Wednesday by the Centers for Disease Control and Prevention, cover the week ending December 20. Unfortunately, Maryland is one of the “hot spots” for Influenza this year, as evidenced by this map of the US.

Influenza Intensity US, 2015

Influenza Intensity US, 2015

In the week ending December 20, nearly 7% of deaths were blamed on pneumonia and flu. That’s higher than it was at the same time last year, but later on in the season the percentage of deaths blamed on the flu generally goes higher.

The number of children killed by the flu spiked in 2013. Thirty-seven deaths were blamed on the flu in the 2011 to 2012 season; the next season, 2012-2013, there were 171 deaths, the CDC says. In the 2013 to 2014 season, the figure was 109.

Pediatric Deaths due to Influenza, through Dec 20, 2014

Pediatric Deaths due to Influenza, through Dec 20, 2014

Evolve Medical feels it is important to understand and appreciate these numbers and asks adults and parents to make sure you are vaccinated against influenza this year. Although it is  an unusually bad year for the vaccine, getting vaccinated is still very important.

“It is the best way to reduce the chances that you will get seasonal flu and spread it to others” and “may make your illness milder if you do get sick,” according to the CDC.

CDC recommends a three-pronged approach to fighting flu: get vaccinated, take everyday preventive actions to help stop the spread of germs and take antiviral medications to treat flu illness if your doctor prescribes them.

Why is this year’s flu season so bad?

For one thing, the dominant version of the virus this year is H3N2 – which tends to lead to harder-hitting flu seasons. “H3N2 predominant seasons tend to have more hospitalizations and more deaths,” CDC director Thomas Frieden warned in early December.

There’s an even bigger potential problem: “the most concerning thing about the flu season this year there is a mismatch between the predominant strain that is circulating and what was put in the vaccine,” Trish Perl, the head of the Johns Hopkins Medicine Office of Epidemiology and Infection Prevention told The Post.

The vaccines distributed this year have limited effectiveness against some “drifted” (i.e. antigenically different ) H3N2 viruses present in this year’s outbreak. A “drift” is a problem for the effectiveness of vaccines, albeit one not quite as devastating as an abrupt “antigenic shift,” which leaves much of the population without an immunity to the new form of the virus. Such a “shift” preceded the 2009 pandemic, for example.