Update on influenza for 2020 to help you and your patients be prepared.
Influenza can be diagnosed at any time of year. However, you are more likely to receive that positive screening between the months of October and May; we see an influenza spike between December and February.
The 2018-2019 influenza season was the longest season that we’d seen in over a decade. William Schaffner, MD, an infectious disease specialist and professor of preventive medicine at Vanderbilt University School of Medicine in Nashville, stated, “Each season is distinctive. Last year certainly was. Usually, there’s a dominant influenza strain throughout the entire season. Last year…we kind of had two seasons.”
According to Dr. Schaffner, at the beginning of the influenza season, most of the people infected had H1N1. By the end of the season, H3N2 showed up, making larger groups of people sicker and creating a second wave of infections.
So, what’s going on for the 2019-2020 influenza season?
This year’s vaccine is formulated to protect against H1N1 and H3N2, the two most prominent types of influenza last year.
Recent reports also indicate that this year’s vaccine is more effective against influenza than it has been in the past several years – its effectiveness is estimated at 45 percent, the highest since the 2015-2016 season.
- In 2016-2017, effectiveness was estimated at 40 percent
- In 2017-2018, effectiveness was estimated at 38 percent
- In 2018-2019, effectiveness was estimated at 29 percent
Influenza changes from year to year; the influenza vaccine must change to keep up. The influenza vaccine from last year will likely be ineffective for influenza that has been predicted for this year.
In order to create a proper influenza vaccine, researchers must attempt to predict what types of influenza will be prevalent – before influenza actually begins to occur. Then the vaccines are created.
Vaccines help the body to create antibodies approximately two weeks after the vaccine is received. According to the CDC, “These antibodies provide protection against infection with the viruses that are in the vaccine. The seasonal flu vaccine protects against the influenza viruses that research indicates will be most common during the upcoming season.”
Experts recommend that everyone, ages 6 months and above, receive an influenza vaccine. There are various types available:
- The “shot” is given as an injection, typically in the arm
- Nasal spray is given as a live attenuated influenza vaccine (LAIV) through the nares
- Quadrivalent influenza vaccine protects against four different types of influenza
- Jet injector is approved for ages 18 through 64
- High-dose flu vaccine contains 4 times the amount of antigen and is approved for those over the age of 65
- Adjuvanted vaccine has an additive that creates a stronger immune response and is approved for those over the age of 65
- Cell-based flu vaccines are grown in cultures of mammalian origin rather than in hens’ eggs
- Recombinant flu vaccines are approved for those with egg allergies
- Intradermal flu vaccine is given into the skin instead of the muscle
Influenza symptoms differ in each person – though the symptoms are characteristic of influenza, they can be confused with the common cold and upper respiratory infections. The symptoms may not all occur in each person. However, one thing is typical – the symptoms common on rapidly.
Common symptoms include:
- A high fever
- Sore throat
- Runny and stuffy nose
- Muscle and body aches
- Vomiting and diarrhea, though this is more common in children
Influenza is caused by a virus; this means that there is no “cure” and the virus must run its course.
Generally, people infected with influenza can expect a mild illness and do not require any further treatment such as medical care and antiviral medications.
While ill, it is recommended to stay home and rest. Avoid contact with others to prevent infecting them. Cover coughs and sneezes as influenza is passed on through droplets. Wash hands frequently.
Some healthcare providers may opt to treat influenza with antiviral medications; these medications may lessen the length of influenza. Those who are very ill or who are part of an at-risk population, such as young children, people 65 and older, pregnant women, and those with certain medical conditions, are more likely to be prescribed an antiviral medication because they are at a higher risk of developing an influenza-related complication.
The CDC recommends staying home for 24 hours after the fever subsides without the use of fever-reducing medications, such as acetaminophen and ibuprofen.
The Bottom Line…
We may have a couple of months left of the influenza season, but we’re hopefully on the downward slope. Keep up the handwashing, folks!
Boatman, M. (2020, February 25). Weekly flu report says this year’s vaccine is more effective. Holland Sentinel. https://www.hollandsentinel.com/news/20200225/weekly-flu-report-says-this-years-vaccine-is-more-effective
Different types of flu vaccines. (2019, September 4). Centers for Disease Control and Prevention. https://www.cdc.gov/flu/prevent/different-flu-vaccines.htm
Flu symptoms & diagnosis. (2019, July 10). Centers for Disease Control and Prevention. https://www.cdc.gov/flu/symptoms/index.html
Flu: what to do if you get sick. (2019, October 8). Centers for Disease Control and Prevention. https://www.cdc.gov/flu/treatment/takingcare.htm
Weiss, K. (2020, January 15). Flu report: What to know about the 2019-2020 flu season. Everyday Health. https://www.everydayhealth.com/flu/flu-report-what-to-know-about-the-flu-season/