By Charly SHELTON

It begins in the last weeks of the year, and can last for several months: flu season. Almost every year, the flu virus reaches epidemic levels, meaning it exceeds the expectations of growth in number of cases, and the 2017-18 flu season is no different. But this season is especially impactful to the country – and the world – because it is not only hitting hard, it’s also vaccine-resistant.

“So far this season, influenza A, H3N2, has been the most common form of influenza. These viruses are often linked to more severe illness, especially among children and people age 65 and older,” said Dr. Brenda Fitzgerald, director of the Centers for Disease Control, during a recent media update. “When H3 viruses are predominant, we tend to have a worse flu season with more hospitalizations and more deaths. While our surveillance systems show that nationally the flu season may be peaking now, we know from past experience that it will take many more weeks for flu activity to truly slow down.”

The H3N2 virus was the culprit in the flu season of 2012-13 and the especially bad year of 2014-15. Though less common, there have also been cases reported this year of H1N1, the virus behind the Spanish Flu deaths of 1918, and the swine flu of 2009.

“With the geographic spread, or where flu is happening, I think the simplest way to describe it is that flu is everywhere in the U.S. right now. There’s lots of flu in lots of places. Our team that does this kind of surveillance studies has been doing this for 13 years and this is the first year we had the entire continental U.S. the same color on the graph, meaning there’s widespread activity in all of the continental U.S. at this point,” said Dr. Daniel Jernigan, director of the Influenza Division in the National Center for Immunization and Respiratory Diseases (NCIRD) at CDC.

He added that the season started early and is probably peaking about now. Compared to past activity, the season is looking a lot like that from 2014-15 and from 2012-13.

“Both of those seasons were seasons where the strain H3N2 was predominant, a strain that is going to be associated with more cases, and it’s going to be associated with more hospitalizations and more deaths,” Jernigan added.

The H3N2 virus is resistant to the flu vaccine due to a last minute mutation of the virus’ surface proteins while the vaccine was in the lab, incubating in chicken eggs. By the time the vaccine was ready, the virus had evolved resulting in a 30% success rate of the vaccine in America and the UK, and about 10% effectiveness in Australia. Despite that, the flu vaccine is still an important safeguard not only against the naturally resistant H3N2 flu, but all of the other strains of flu that will come out later in the season.

“We continue to recommend the flu vaccine. While our flu vaccines are far from perfect, they are the best way to prevent [illness] from the flu and it is not too late to get one,” said Fitzgerald. “As of last month, manufacturers reported that they have shipped more than 151 million doses of flu vaccines, so it should be readily available.”

In addition, common sense health habits are important for people to keep their immune systems strong. These include washing hands regularly, trying to not touch their faces, avoiding sick individuals and taking extra Vitamin C to boost their immune systems.

“Research is still looking at the link of enhancing the immune system through diet and exercise, and diet and exercise are things we can control that can naturally keep our system functioning properly,” said Cortney Montgomery, RD, CNSC, director of Clinical Nutrition with Keck Medicine of USC. “There are unhealthy foods, lifestyle choices and environmental effects that impact our bodies’ ability to perform at the optimal level. Choices to consider that impact our health are smoking, quality sleep, hydration, eating proper fruits and vegetables, reducing our intake of fast food or fried foods at home, exercise or lack of physical activity, consumption of sugary drinks, and consumption of alcohol.”

More healthy tips can be found at CDC.gov/flu/prevent.

  Charly Shelton