Just as Madison makes its annual seasonal transition from fall to winter it also enters a season of a different type; the flu season. Every year starting in early October and lasting until the end of May, the contagious seasonal influenza virus spreads across the United States causing widespread illness and sometimes severe, life-threatening complications. While regular hand washing, not sharing food and avoiding touching your hands to your face have been shown to decrease the likelihood of getting infected with the virus, the single most effective way to prevent getting the virus is to get the seasonal flu shot at the start of the flu season each year.
Fortunately for University of Wisconsin- Madison students and employees, you do not have to go far to receive the flu vaccination as they are available at all UW-Health primary care clinics as well as at UW-Health pharmacies. Appointments usually take about ten minutes and afterwards the vaccine is effective for up to one year.
Seasonal influenza, or the flu, is a contagious respiratory illness which infects 5-20 percent of the U.S. population every year.
Common symptoms of the flu include fever, sore throat, dry cough, runny nose, head and body aches as well as general fatigue. Dr. James Conway, fellowship director of UW-Madison’s Division of Pediatric Infectious Diseases, explains that “while most people with the flu do okay and are able to manage the symptoms, it is still a miserable illness that can keep you from being productive for a week.”
Each year complications of the flu send over 200,000 Americans to the hospital and even kill thousands. While the majority of children and the elderly in the U.S. received the flu shot last year, only about one third of adults aged 18-64 received the vaccine. High risk individuals, including young children, the elderly and people with chronic health problems, are more likely to develop serious complications.
“If you get enough people to become socially conscious about not spreading the virus by getting vaccinated, we can make it hard for the virus to spread to populations that have a higher chance for serious complications to occur,” Conway said.
The flu vaccination stimulates an individual’s immune systems to create antibodies for the flu virus that recognize and eliminate it without having the have the person to become infected first.
The main component of the vaccine is antigenic material which is either a weakened or killed form of the flu virus that is not infectious. The immune system recognizes this material as foreign so it creates antibodies that will destroy any agent similar to it such as the actual live flu virus that is able to infect humans.
There are two types of flu vaccines; the inactivated or recombinant form, and the Live Attenuated Influenza Vaccine (LAIV). The inactivated form is the most common flu vaccine which is injected with a shot. This form does not contain the live influenza virus.
LAIV contains a live version of the virus but it is attenuated, or weakened, so that it will only allow the body to produce the antibodies for the virus without actually infecting you. This vaccine is given in the form of a spray into the nose. Since it does contain a live version of the flu virus, the Center for Disease Control and Prevention (CDC) recommends that pregnant women or people with a weakened immune system receive the inactivated form instead.
The vaccine is recommended yearly due to the fact that the flu virus can change its genetic makeup causing the previous year’s vaccine to become ineffective. This virus is able to undergo two distinct antigenic changes which allow it to become “hidden” from the antibodies your body may have produced for previous flu viruses.
The first is called antigenic drift which occurs when small changes in the genes of the flu virus happen over time as the virus replicates itself. If these small changes from antigenic drift accumulate enough over time, it can result in an antigenically different virus that your immune system will not be able to recognize. This is why the CDC updates the vaccine formula each year to keep up with the changing virus.
The second, less common way the virus is able to undergo antigenic changes is through a process called antigenic shift where a rapid change of the genetic makeup of the influenza virus occurs that produces new proteins in the virus that are able to infect humans. Since this shift is so extreme compared to antigenic drift, most people will not have immunity to the new virus which allows for the possibility of a pandemic.
An example of this occurred in the spring of 2009 with the spread of the H1N1 flu virus. The flu vaccines given at this time did not allow the immune system to produce antibodies for this drastically different virus and a pandemic occurred throughout the world.
While there are potential side effects to the vaccine, they are all minimal and only temporary. These side effects include dizziness, itchy eyes, cough, fatigue and soreness or swelling in the area you received the shot. While the flu vaccine has been shown to be an effective method in flu prevention, it is only, on average, 70-90 percent effective.
However, “the beauty of these vaccinations is that they have been around for decades. The flu vaccine is one of the most researched vaccines on the face of the earth. They are incredibly safe and the companies that produce them are always coming up with ways to make them safer and more efficient,” Conway said.