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The Flu Vaccine: To Stick or Not to Stick

Justin Amaker

November 10, 2008



As the leaves begin to fall and the wind begins to bite, there is typically one thought on the minds of many Americans: ski season! However, while many individuals are packing their skis, snowboards and SUV’s for their extended weekend getaways to the slopes, health care officials have a thought of a different sort.  A thought that will slowly begin to develop into a strong concern as the winter months draw closer. This concern is shared by health care officials not only across the country, but around the world. A concern for the approaching flu season and the effect it will have on their local populations.

According to the Center for Disease Control (CDC), the “flu season in the United States usually ranges from November through March, and sometimes into early spring” ( With such a broad time span, there is no surprise that “5 to 20 percent of Americans come down with the flu during each flu season” (  

The flu is one of the most preventable illnesses with two methods of vaccinations currently available that offer protection for individuals from the influenza virus. Though these vaccines are available, a great number of individuals are still affected by the flu every year. Why are there still a great number of individuals coming down with the flu when vaccines are available? What is known about the flu and the flu vaccine? And most of all, does the flu vaccine itself make patients sick?



What is the Flu?

To understand any claims that are being made regarding the flu vaccine, the vaccine and the virus must be understood. The Center for Disease Control states that “Influenza is a contagious respiratory illness caused by [the] influenza viruses” (


From the onset of symptoms until close to the end of the illness, the person infected with the influenza virus is contagious which makes the flu easily transmissible. In very few cases, the flu virus can lead to several other conditions that may deem to be life threatening to the patient. “[M]ore than 200,000 people are hospitalized from flu complications and about 36,000 people die from flu. Some people such as the elderly, young children, and people with certain health conditions, are at high risk for serious flu complications” (  

Several symptoms of the flu include dry cough, chills, muscle aches, fatigue, fever and in some cases diarrhea.


The Flu Vaccine

What’s in a Flu shot?

The fundamental components of a flu shot are the inactivated strains of the influenza virus, a cultivation medium and several preservatives. “The flu shot is an inactivated vaccine (containing killed virus) that is given with a needle, usually in the arm. It contains three influenza viruses. The three vaccine strains – one A (H3N2) virus, one A (H1N1) virus, and one B virus – are representative of the influenza vaccine strains recommended for that year. Viruses for the flu shot are grown in eggs” ( Since the flu vaccines are made within chicken embryos, many Public Health organizations recommend those allergic to egg products not to receive the flu vaccine.

In addition to the inactivated strains of influenza that are cultivated within the chicken embryo, there are also preservatives put into the vaccine. These preservatives keep the influenza strains inactivated.


How does the flu vaccine work?

As a result of the vaccine containing several killed strains of the influenza virus, the patient’s immune system identifies these inactivated strains as a virus and begins to build up antibodies in the blood stream. After approximately two weeks these antibodies are found throughout the patients entire blood supply. If and when the patient comes in contact with the influenza virus, these antibodies seek and destroy the strain on contact, ultimately preventing the flu.


The Claim

Flu shots give you the flu

There is a notion that the flu vaccine can make patients sick. This is usually heard by word of mouth or found on the World Wide Web. One of the primary reasons individuals choose not receive flu shots is linked to the thought process that leads to many people making the claim that the influenza vaccination itself causes the flu because it contains strains of the virus. Throughout the internet there are claims of individuals coming down with the flu or flu like illness after the shot has been administered. After receiving these vaccinations, many people report feeling nauseated and fatigued in conjunction with a low to mid grade fever.

Typically, these claims can be found in online blogs or on homemade health care advice websites with the average person making the claim that the flu shot they or their family member recently received made them sick as seen in a few of the links below:

·         The Questions of Flu Shots 

·         Why does the flu shot make some people sick?

·         Have you gotten the flu shot?

These individuals usually feel they were fooled into getting the flu shot to protect their health or the health of a family member’s, then in turn become sick with the flu. Just as individuals discuss a bad product that a company may produce to save others the hassle, so do sick patients as they look to place the root or blame of a problem on something that their anger can be directed towards. This evidence lacks quality in that the only evidence to support these claims is their own personal experiences and no scientific evidence.


The Research

Though there are numerous experiments and studies held regarding the effectiveness of the influenza vaccine on various populations, there are few if any done specifically to discover whether the flu shot truly makes individuals sick. Since most of the information found was testing something other than the adverse effects of the flu shot, my argument will be based off of the research found.

A study performed by Dr. Douglas S. Campbell and Maria H. Rumley, RN, sought “to determine if the influenza vaccine can reduce absenteeism and the cost of Influenza-Like Illnesses (ILI) in health adults in the workplace, a prospective, non-randomized, non-placebo control trial was done…” (Campbell and Rumley, 1997). The study involved individuals who volunteered to receive the influenza vaccine and those who opted not to receive the flu vaccine.

The results of Campbell and Rumley’s study were as follows. “Compared with the unvaccinated workers, the vaccinated workers had significantly fewer workers with ILI (20% vs. 49% P=0.00000008), workers reporting lost workdays (11% vs. 24%, P=0.01), and total lost workdays because of ILI (43 vs. 93, P=0.00004)” (Campbell and Rumley, 1997).

Cumulative number of Influenza-Like Illness cases by week of study. Solid line vaccinated employees; dotted line, unvaccinated employees.

Source: Journal of Occupational and Environmental Medicine, Volume 39(5), May 1997, pp 408-414


There were workers who experienced side effects of the vaccine including “body aches (10, or 7.4%) and sore throat (10, or 7.4%). Other symptoms reported included headache (7, or 5.2%), weakness, chills, cough and sneezing (3, or 2.2%), fever (2, or 1.5%)…There were no lost work days attributed to the vaccine” (Campbell and Rumley, 1997).

The study performed by Campbell and Rumley is not only useful in determining the cost-effectiveness of the influenza vaccine, but also get an idea of how many individuals became sick at any point after receiving the vaccine. The main objective of the study was accomplished in addition to other objectives. The only critique I have with the study, as with any other study involving flu vaccinations, is that most do not take into account the other strains of the influenza virus that may be going around at the time of study.

Another study performed at the Saint Louis Medical Center by a group of doctors sought to “compare the immunogenicity and safety of injection of TIV across different dose levels (3, 6, 9, and 15 μg/antigen/dose) and different routes of administration (IM versus ID). The study was a single-center, prospective, randomized, active-controlled, open label clinical trial. Approximately 31 subjects per group (217 in total) were to be enrolled to each of the following groups determined by dose and route of administration” (Belshe, Newman, Wilkins, Graham, Babusis, Ewell and Frey 2007).

A similar study was performed by the Center for Disease Control using the flu vaccination and placebo to determine the side-effects of the shot. “In placebo-controlled studies among adults, the most frequent side effect of vaccination was soreness at the vaccination site (affecting 10%--64% of patients) that lasted <2 days. These local reactions typically were mild and rarely interfered with the recipients' ability to conduct usual daily activities. Placebo-controlled trials demonstrate that among older persons and healthy young adults, administration of TIV is not associated with higher rates for systemic symptoms (e.g., fever, malaise, myalgia, and headache) when compared with placebo injections” (

As with the first study, both of these studies were created to test the effectives of specific flu vaccinations on patients. And just with the first study, there were few if any individuals who became sick from the injections. So although the key objective in these studies was not to find if the flu vaccine makes individuals sick, it provided results on the issue.

Both of these similar studies involved the right amount of individuals and tested for what needed to be done so their objective was accomplished.




Does it make you sick?

Based on the research and experiments I analyzed that involve the flu shot, there is no valid support to say that the influenza vaccine can give an individual the flu. However, I will not discredit the individuals who said they have become sick after receiving a flu shot. There are several possibilities as to how this can happen.

To help alleviate the burden of large quantities of vaccines that will be demanded during the upcoming flu season, pharmaceutical companies make them well in advance. As a result of this, the companies along with health care officials must determine which strains of the influenza virus will be most prominent. The vaccine is then created from the top three strains of this prominent list. However, the problem arises when people are affected by other strains. There are several strains of the flu that typically go around in a given flu season. The shot that most people receive will not protect you fully from every strain. This leaves many patients vulnerable to one of the influenza strains not covered by the vaccine. Individuals can be exposed to these other strains immediately following receiving the shot and come down with the flu in days to weeks. People will then, in their mind, connect their sickness to the flu vaccine they recently received.

Another strong possibility may be linked to the fact that some individuals mistaken the side-effects of the flu vaccine for symptoms of being infected with the influenza virus. There are just a few side-effects and symptoms that both of them share, but because of this, it may lead some to believe that they have the flu as well.


Symptoms and Side-Effects of Flu and Flu Vaccine

Influenza Virus

Flu Vaccine

-High Fever

-Fever (low-mid)

-Severe Aches and Pains

-Aches and Pains



-Dry Cough




-Sore Throat


-Watery Discharge from Nose



All of these are justified reasons as to why individuals believe a flu shot will make you sick. For many, simply knowing that a doctor or health care official is injecting them with an inactivated virus frightens them to the point where they refuse to receive a flu vaccination. This mentality leads to an increase in the number of individuals affected by the influenza virus and even the number of critical hospitalizations and deaths per year from the virus as well.


Based on the facts, it would be my recommendation for every individual (Yes, you too!) to receive the influenza vaccination shot. By receiving the vaccination, you decrease your risk of being affected by the virus or passing the virus along. Many complications can arise as a result of being infected with the influenza virus and this is a risk people should not take. So next time you are offered a flu shot, say yes. Say yes for yourself, your friends and your community, because in the end we are all affected by each other’s decisions.                 




Campbell, D. S. MD, MPH & Rumley, M. H. RN 1997. Cost-Effectiveness of the Influenza        Vaccine in a Health, Working-Age Population. 39(5). 393-482

Belshe, R.B MD, Frances K. Newman, F.K MS, Wilkins, K PhD, Graham,  I.L MD, Babusis, E. MD,1 Ewell M.               MD, and Frey,  S.E. MD 2007. Comparative Immunogenicity of Trivalent Influenza Vaccine                               Administered by Intradermal or Intramuscular Route in Healthy Adults. 25(37-38). 6653-6657




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