I have this running experiment, where I am the population being studied. The design is pretty simple. Some years I take the flu shot, some years I don’t. So, the independent variable (the variable that I change) is getting the flu shot or not and the dependent variable is whether or not I get the flu. The goal: to observe flu vaccine effectiveness in this very small sample.
This study began in 2009, amidst the backdrop of the H1N1 swine flu “pandemic.” That year I took the whole family with me to the local junior high where they were giving away vaccines like candy. They even had the nasal spray vaccines for the kids. It was a regular carnival. Are you disturbed yet?
So far results are:
Every year (100%) I have been vaccinated (3 years, not including this year) I have not shown signs of contracting influenza.
Fifty-seven percent (4/7) of the years I have not been vaccinated I have shown signs of contracting influenza.
Forty-three percent (3/7) of the years I have not been vaccinated I have not shown signs of contracting influenza.
I will keep you informed as this season progresses. I received my flu shot five days ago.
Other than telling you all about my little experiment, I am writing this post to make the case that I make to my biology students when we discuss viruses: not all viruses are created equally and not all vaccines are created equally. There are a wide variety of viruses (bacteriophages and adenoviruses, for example). Viruses are host specific and so are often categorized by the creature they infect. Tobacco mosaic virus, for example, was originally found to infect tobacco plants, but is now known to infect many more plant species. Viruses infect plants, animals, bacteria, protists, and fungi.
Viruses and vaccines intrigue most of my students. Viruses, after all, are the undead, the zombies, not meeting the criteria necessary to be considered alive, but certainly not inanimate either. Evolutionists think “that viruses may have evolved alongside the very first ‘living’ cells,” because their genetic structure is similar to that of many creatures they infect. These similarities could also easily be explained by our creator’s use of a common design framework (order, complexity, responsiveness). Some creationists believe that current harmful viruses could have descended from ancestor viruses that were once not harmful. For more on the origin of viruses from a Creationist perspective as well as a thorough treatment of their ability to acquire and pass on the DNA of other creatures check out this article by Berglund.
All of this is interesting stuff, but how about some practical considerations of the influenza vaccine and a few others.
- Effectiveness: according to the CDC, the influenza vaccine (now a combination of four different inactivated flu strains) is 40-60% effective. Interestingly the LAIV (Live attenuated influenza vaccine), first available in 2003, is no longer recommended by the CDC as it is considered relatively ineffective (46% in 2015-16 compared with the shot, 65%, CNN article). This is the nasal spray variety I mentioned above. Flu vaccines are considered effectively for only one season.
- The DTaP and Tdap vaccines (batched to simultaneously to protect against tetanus, diptheria, and pertussis) requires regular boosters to remain effective. “CDC’s current estimate is that in the first year after getting vaccinated with Tdap, it protects about 7 out of 10 people who receive it. There is a decrease in effectiveness in each following year. About 3 or 4 out of 10 people are fully protected 4 years after getting Tdap.” The pertussis vaccine or whooping cough has become notorious for its ineffectiveness. Increased outbreaks in recent years, interestingly, occurred in vaccinated populations primarily.
- MMR (measles, mumps, rubella):
- Side Effects: all vaccines have potential side effect as do all pharmaceuticals. Some are quite serious.
There are other important factors to consider as well. How virulent and prevalent is the virus? In other words is getting vaccinated worth the cost, hassle, and potential side effects. Also, how are the vaccines sourced? Do vaccines descend from aborted fetal tissue?
A few answers.
- Influenza sourcing: influenza vaccines are egg-based. Other mammalian sources are in the works for people allergic to eggs.
- MMR sourcing: Rubella vaccine is based on aborted fetal tissue
- Hepatitis A vaccines [VAQTA/Merck, Havrix/GlaxoSmithKline, and part of Twinrix/GlaxoSmithKline]
- Varicella (chickenpox) vaccine [Varivax/Merck, and part of ProQuad/Merck]
- Zoster (shingles) vaccine [Zostavax/Merck]
- Adenovirus Type 4 and Type 7 oral vaccine [Barr Labs]
- Rabies vaccine [IMOVAX/Sanofi Pasteur]
This sourcing information comes from The History of Vaccines, an educational outreach from the College of Physicians of Philadelphia.
These questions matter and contribute to my “viruses and vaccines are not created equally” hypothesis. So do your homework and stay tuned for results on this year’s flu vaccine research.