Most people, today, are more aware of the ill effects of vaccination than they were 50 years ago. Public awareness of health, disease and treatment options has increased multifold with the use of the internet and the media.
Should I vaccinate or not? Is it the right time, should I wait? Are the vaccines safe? Will it really protect my child from the disease (how effective is the vaccine?) Are the risks of taking the vaccine shot greater than the risk of the disease itself? Will it confer lifelong immunity? (Does it mean booster shots are involved?) Does the state/school require me to vaccinate against a particular disease? These are some questions most parents ask of themselves when they take their little ones to get the shots. This is a tough decision that most parents need to make. Making an informed decision gives us the satisfaction of at least having tried to give our children the best of the knowledge that was available at the time.
The American Academy of Pediatrics (AAP) notes the dilemma faced by many parents in that vaccines are a very safe and important health intervention, but are neither risk-free nor 100% effective. It advises physicians to respect the refusal of parents to vaccinate their child after adequate discussion, unless the child is put at significant risk of harm
What is an infant's immune system like?
I want to start by writing about an infant's immune system because most of the vaccines are given to children under the age of 2 years. The immune system is an intricate network of interdependant organs and cells. To oversimplify this most important functional unit of the body is doing injustice to the system and all the research done to study its functions. The most simplified version is as follows. When a baby is born, he or she has some antibodies from the mother's placenta which protects the infant to some extent from infections. The immunity that the baby received from the mom at birth gradually fades around 6-8 months of life. Babies that are breast fed continue to receive many important antibodies in the colostrum (breast milk immediately after birth). The baby's own immune system starts developing at about 6 days after birth the serum concentration of specific antibodies rises sharply until adult levels are achieved which happens approximately by the end of first year.
If this is true (which it is), then the timing of vaccination is very important.
How are Vaccines tested before they are out in the market?
Vaccines are initially tested on animals. Pre-licensure, the manufacturer of the vaccine conducts phase 1 through Phase 3 trials on humans. Phase 1 studies are about establishing the safety and immunogenicity and are performed in a small number of closely monitored subjects. Phase 2 studies are dose-ranging studies and may enroll hundreds of subjects. Finally, Phase 3 trials typically enroll thousands of individuals and provide the critical documentation of effectiveness and important additional safety data required for licensing.
Until a vaccine is given to the general population, all potential adverse events cannot be anticipated. Thus, many vaccines undergo Phase 4 studies-formal studies on a vaccine once it is on the market. Basically, it is studied in thousands of children to look for side effects (what they call 'rare' side effects which affect 'only a small number of children'). For example, a rotavirus vaccine was withdrawn in 1999 after it was linked to intestinal blockage in about 100 children.
The government relies on the Vaccine Adverse Event Reporting System (VAERS) to identify problems after marketing begins, but it is common knowledge that there are very few parents who report adverse reactions to the doctors unless it is life threatening or disabling. Often subtle changes in behavior and personality of the child after vaccination are completely missed.
Stay tuned for more information on this blog
Questions like:
- What is the link between vaccination and autism and mitochondrial disease?
- What is herd immunity?
- What are the different types of vaccine?
- Immunity conferred by natural disease as opposed to vaccine.
- What are your options if you do not want to vaccinate?
- What is the optimal timing of vaccination?
- What is the individual susceptibility risk and hence identifying the need to be vaccinated?
And many more.
References
- http://www.fda.gov/BiologicsBloodVaccines/DevelopmentApprovalProcess/BiologicsLicenseApplicationsBLAProcess/ucm133096.htm
- http://www.aap.org/advocacy/releases/autismparentfacts.htm
- http://www.cispimmunize.org/fam/facts/VaccineSafety_English.doc
- 'The Vaccine Balancing Act', a seminar on Vaccination by Heather Zwickey, PhD, Research scientist with specialty in clinical medicine and Dr.Hilary Andrews, ND
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