A recent study, published in the journal Vaccine, provided evidence that the new 13-valent pneumococcal conjugate vaccine (PCV13) is as safe as the previous version, the 7-valent pneumococcal conjugate vaccine (PCV7). The newer version of the vaccine, introduced in 2010 after clinical trials, protects against a broader range of pneumococcus (Streptococcus pneumoniae, a significant human pathogenic bacterium) subtypes. These studies show that the new version did not increase the risk for any serious adverse events related to the vaccine.
Pneumococcal disease is a serious health care issue, especially for children and adults with certain risk factors. Pneumococcal disease can lead to various serious diseases like pneumonia and bacterial meningitis, or less serious ones like otitis media. Unfortunately, pneumococcal disease can be fatal. In some cases, it can result in long-term problems, like brain damage, hearing loss, and limb loss.
The study, which was funded by the Centers for Disease Control and Prevention, researchers at Kaiser Permanente (KP) evaluated the electronic medical records of nearly 600,000 children, ages 1 to 24 months, who received the PCV13 vaccine over a two year period. What is great about KP is that it is a highly integrated health care system that collects all of its patient’s medical records in a centralized manner, no matter if the patient goes to a hospital, sees a specialist or gets a vaccination. They can track patients for a substantial number of years, and because of the broad ethnic and economic base of its patients, it can bring considerably large numbers to a research study.
The results of the study were out of 600,000 injections of PCV13 vaccine :
- 87 incidents of febrile seizure (a convulsion resulting from a rapid rise in body temperature), or a rate of 1.5 out of 10,000.
- 5 incidents of encephalopathy (a general description of a brain disorder, but not a specific one), or a rate of 1 out of 100,000
- 62 incidents of asthma, or a rate of about 1.3 out of 10,000
- 7 incidents of Kawasaki disease (an autoimmune disease), or a rate of about 1 out of 100,000
These rates are no different than PCV7 and are not statistically different than background rates of these diseases. In other words, although they happened after the vaccination, there is no indication that the vaccines, or just random background incidents, caused these adverse reactions. Moreover, and this is important, the death rate of those who get pneumococcal pneumonia can be up to 10%. That means out of 100,000 children who are hospitalized for pneumococcal pneumonia, about 10,000 will die, even with treatment with antibiotics and other medications. The same can be said of pneumococcal meningitis.
The authors conclude that:
In conclusion, safety surveillance at VSD (Vaccine Safety Datalink Project) is not intended to provide conclusive evidence of causality. Rather, it is a method to quickly detect potential associations between a vaccine and an adverse event so that a thorough investigation can be planned. In this study, we identified potential signals for encephalopathy and Kawasaki disease following PCV13 vaccination. Evaluation these signals through medical record review failed to confirm the PCV13 associated encephalopathy, however the association of Kawasaki disease and PCV13 may deserve further investigation. Based on 90 weeks of data including approximately 600,000 doses of PCV13 collected at the Vaccine Safety Datalink Project, we identified no significant increased risk of pre-specified adverse events associated PCV13 vaccine comparing to PCV7 vaccine.
Just to dissuade anyone from misinterpreting the conclusion, the researchers found nothing significant about a correlation between Kawasaki disease and PCV13. The numbers are so low (only 7 incidents), it would be impossible to draw any conclusion without a larger base of data, or someone showing actual causality. There is no evidence here to suggest correlation or causation, just a thought that maybe someone should take a look, just in case.
“It is important that children receive the pneumococcal conjugate vaccine as it provides protection against very serious and potentially fatal infections, including meningitis and bloodstream infections. The new vaccine protects against an additional six types of pneumococcal bacteria,” said study lead author Hung Fu Tseng, PhD, MPH, a research scientist at the Kaiser Permanente Southern California Department of Research & Evaluation.
Vaccines save lives.
- Tseng HF, Sy LS, Liu IL, Qian L, Marcy SM, Weintraub E, Yih K, Baxter R, Glanz JM, Donahue J, Naleway A, Nordin J, Jacobsen SJ. Postlicensure surveillance for pre-specified adverse events following the 13-valent pneumococcal conjugate vaccine in children.Vaccine. 2013 Apr 8. doi:pii: S0264-410X(13)00375-7. 10.1016/j.vaccine.2013.03.040. [Epub ahead of print] PubMed PMID: 23579258.
- Yih WK, Kulldorff M, Fireman BH, Shui IM, Lewis EM, Klein NP, Baggs J, Weintraub ES, Belongia EA, Naleway A, Gee J, Platt R, Lieu TA. Active surveillance for adverse events: the experience of the Vaccine Safety Datalink project. Pediatrics. 2011 May;127 Suppl 1:S54-64. doi: 10.1542/peds.2010-1722I. Epub 2011 Apr 18. PubMed PMID: 21502252.