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Excerpt from Vaccine Science Revisited: Are Childhood Immunizations As Safe As Claimed?:


Pneumococcal vaccine � The many shades of Prevnar

“I have a public bathroom rating system that I keep in my head, and anything that I think rates lower than two stars, I won't even enter.� Sally J. Pla (The Someday Birds)


Streptococcus pneumoniae are a family of organisms that many people have been infected by at some point in their lives. This family (strep) has at least 90 different strains of the bacterium called pneumococcus.

Every year, pneumococcus is responsible for a wide range of medical problems in the US, including bacterial pneumonia, bacteremia, ear infections in infants and young children and, as discussed in previous chapter, bacterial meningitis.

Although ear infections are extremely common in young children, the FDA announced that the new vaccine prevents blood poisoning and meningitis, but not ear infections. A person becomes infected when they inhale the droplets that are shed into the air by an already infected individual. Once a person has become infected, the bacteria then enters the bloodstream. From there it can travel to the brain or lungs. Those who have weak immune system may suffer secondary complications like pneumonia.
The pneumococci bacteria live as normal biota in the throat and nose of some individuals. These individuals don’t become sick (from the bacteria) nor do they need treatment because the bacteria don’t cause disease. Those individuals who don’t have it as normal biota in their throat and nose, and instead become sick, are treated with antibiotics. Normally, it only takes about two days or less to get better.

There are two types of pneumococcal vaccines used in the US today. These are the pneumococcal conjugate vaccine (PCV or Prevnar) and the pneumococcal polysaccharide vaccine (PPSV or Pneumovax).

According to the CDC website, the PPSV should not be given to “children younger than 2 years old� and for those children older than two, this vaccine should only be administered if the child has “certain medical conditions�.

As for the PCV vaccine, the CDC recommends that “all children younger than 2 years old� should receive it. For children older than two, the vaccine should only be given for those “with certain medical conditions�.

We found this very interesting because when we looked at the website for Mount Sinai Hospital in Toronto, Canada, according to their microbiology department, the vaccine is “for those at high risk of serious infection.�

Although their website doesn’t mention a vaccine by name, the site is “made possible through an unrestricted educational grant from Pfizer Canada Inc.� Pfizer is the manufacturer of the Prevnar vaccines.

The webpage continues:

“The vaccine is not recommended for children < 2 years as they do not respond satisfactorily. It is not recommended for prevention of inner ear infections of childhood.�

The Mount Sinai Hospital website also points out the specific conditions or illnesses a child must have in order to receive the vaccine. This seems contradictory. It appears the page may not have been updated recently. In the hope of clarifying this, we visited Pfizer Canada’s website. On their webpage, they state that as of December 2009, 120 countries have approved the use of Prevnar 13 in infants and children.

Their American website confirms the use of the vaccine for infants as young as six weeks old. Here, they also state that since 2016, the vaccine Prevnar 13 includes some of the strains that cause ear infection in infants and children. Their Canadian webpage states, as mentioned above, that as of December 2009 the vaccine was approved for infants and children in 120 countries. The American website, states that as of 2016 the vaccine has been used for infants and children in over 150 countries.

Pfizer prides itself in “[m]anufacturing and delivering world-class vaccines� and explains that:

“[…] one dose of Prevenar 13 requires 580 manufacturing steps, over 1,700 employees, 678 quality tests, 400 different raw materials, and more than two-and-a-half years to manufacture from start to finish.�

The vaccine is called Prevnar and the number accompanying the name shows how many serotypes/strains are included in the vaccine.

You can probably already guess what one of the concerns are when a vaccine only covers a fraction of the strains of a certain bacterium. One research paper that brings up such a concern is a paper written in 2007 with the purpose:

“[t]o monitor continuing shifts in the strains of Streptococcus pneumoniae that cause AOM [acute otitis media] […] following the introduction of a pneumococcal 7-valent conjugate vaccine (PCV7).�

The authors found that:

“In the years following introduction of PCV7, a strain of S. pneumoniae has emerged in the United States as an otopathogen that is resistant to all FDA-approved antibiotics for treatment of AOM in children.�

The vaccine approved for children is the Prevnar vaccine. This is, as mentioned above, a conjugate vaccine. Its bacterial sugar coat is grown in soy peptone (protein derivative) broth. A carrier protein is grown in a strain from the C. diphtheriae bacteria in a culture made with bovine protein fragments and yeast products. Because the bacterial sugar coat is too weak to awaken the immune cells, it’s attached to a carrier protein. The carrier protein is much stronger and can aggravate the immune cells. Vaccines that are conjugate vaccines are the vaccines for Hepatitis B, Hib, HPV, pneumococcus and meningococcus.


Ever-changing vaccine

As mentioned above, the pneumococcal family has multiple strains. It was unrealistic for the scientists to make a vaccine that covers all the strains. Instead they picked seven strains and introduced Prevnar 7 to the public. It was a vaccine intended to combat seven out of more than 90 different pneumococcal strains.

Within a few years of targeting these seven strains, the vaccine successfully prevented people from getting sick. As with most things, nature finds its way around obstacles or finds a way to take advantage of them. With these seven strains out of harm’s way, people started getting sick from different strains. These new strains, which had not caused problems in the past, became more prevalent and more dangerous than those they replaced.

In order to keep up, scientists added six additional strains to the Prevnar vaccine. It became Prevnar 13 instead of Prevnar 7. Within a couple of years, these little microorganisms quickly adapted. There are now already new strains taking the place of these 13 strains.

It appears that each time a pneumococcal vaccine is marketed, other serotypes (strains) keep becoming disease-causing. This makes the vaccine less effective against these diseases. So, in order to continue the suppression of the diseases caused by this bacterium (Streptococcus pneumoniae), a new vaccine needs to be continuously developed to cover the new emerging serotypes (strains). This feels a lot like a dog chasing its own tail.


References for Chapter 38: Pneumococcal vaccine � The many shades of Prevnar:

Centers for Disease Control and Prevention. (2017, December 6). Pneumococcal Vaccination: What Everyone Should Know. Retrieved from
Ibid.
Mount Sinai Hospital. Department of Microbiology. (n.d.). What is Streptococcus pneumoniae or pneumococcus?. Retrieved from
Ibid.
Ibid.
Pfizer. (2016, November 16). National Advisory Committee on Immunization (Naci) Gives Prevnar® 13 Grade a Recommendation. Retrieved from
Pfizer. (n.d.). Vaccines. [2016 Annual Review]. Retrieved from
Ibid.
Ibid.
Pichichero, M.E. and Cary, J.R. (2007). Emergence of a multiresistant serotype 19A pneumococcal strain not included in the 7-valent conjugate vaccine as an otopathogen in children. JAMA, 298(15), 1772-1778
Ibid.
Tan T. Q. (2012). Pediatric invasive pneumococcal disease in the United States in the era of pneumococcal conjugate vaccines. Clinical microbiology reviews, 25(3), 409-419.