Influenza season is at full tilt! It started officially in the USA the week of October 5, 2019. It started a month earlier than usual and now all states are reporting significant to widespread influenza infections. Typically, flu season runs from November to March and is usually consists predominately of influenza A infections. This year it’s influenza B causing most of the infections. We are only about halfway through the expected influenza season, so vaccination is still beneficial. I’ve already seen a few children in my clinic that have caught influenza twice this season — influenza B last year and influenza A this year.
Locally, Idaho has reported 6 deaths this year due to influenza, the most recent being last week. Two of these deaths were in children – one in Idaho Falls. A third child death thought to be due to influenza is under investigation in Eastern Idaho.
Across the country, the CDC estimates that there have been 10 to 14 million cases of influenza, 87,000 to 150,000 hospitalizations, and 4,800 to 15,000 deaths this flu season.
Every year from 2010 to 2016, influenza infections were associated with 4.3 to 16.7 million medical visits, 140,000 to 700,000 hospitalizations, and 12,000 to 56,000 deaths. This is on par with the 25,000 to 40,000 gun-related deaths per year. Death happens from influenza by respiratory disease, bacterial complications of the initial infection, and more rarely by brain infections and heart infections. The chances of a heart attack or stroke in susceptible people is 6 to 10 times higher in the week after catching influenza. About 3 of every 1000 persons with influenza will get very sick, resulting in hospitalizations or worse.
Average rates of catching influenza year to year range from 10 to 40% of all people on the planet. You may go a few years without catching influenza, but you’ll eventually get exposed to it. Most people that catch influenza have fevers, muscle aches, runny nose, cough, wheezing, laryngitis for 3-7 days then recover. Vomiting and diarrhea is more common in kids, but adults can experience it as well. Toddlers, babies, and adults over 65 are often sicker and for longer (10 days is common).
Influenza is spread from one person to another by droplets (coughing or sneezing) or by touching a surface contaminated with the virus and then touching your eyes, nose, or mouth. Therefore, cover your mouth when you cough or sneeze, wash your hands with soap and water often, and try not to touch your face unless you wash your hands first. Wearing a mask can help, too, but isn’t foolproof. People in crowded, indoor conditions tend to get influenza more easily then those who work outdoors in uncrowded places. That’s why students in crowded classrooms and those visiting airports, busy amusement parks and stores are the most likely to get exposed to influenza. It takes an average of 2 days from exposure to influenza to show symptoms from the infection. People are contagious a day before they show symptoms. That means you can’t just avoid the sick people since even a well looking person could expose you to influenza.
Even in the middle of the season, the influenza vaccine is the best thing you can do to reduce your risk of contracting influenza. The influenza vaccine is currently available at many doctor’s offices and pharmacies. The vaccine isn’t perfect, but it has been shown to reduce the chance of hospitalization from 60-90%, and the chance of any influenza illness from 30% to 80% depending on the situation. It takes up to five days to start benefiting from the vaccine, but peak immunity from the vaccine can take 4 to 6 weeks. If you get exposed to the flu during this timeframe, you might be inclined to think the vaccine gave you the flu, but this is not true. You cannot get the flu from the vaccine.
I recommend everyone from age 6 months and up get an influenza vaccine every year. It’s only a matter of when you get exposed, and not if you get exposed. The disease is unpredictably dangerous, especially to children, the elderly, and the unvaccinated.
Gregory Kostur, M.D. is Health West’s pediatrician. After working in the US Air Force as a pediatrician until 2008, he worked in private practice near San Antonio, Texas until March of this year.