Saar Kuzi
Alessandra Coutinho Fernandes
William Cope
Richard Tapping
Kashif Ahmad
Reda Sadki
Shubhra Kanti Karmaker Santu
Adam P Rusch
Elizabeth Edwards
Matthew LawFA16 Immunization Module’s Updates
Vaccine Safety
Vaccinations safety is ensured through rigorous research, testing, and quality control. Vaccines are first evaluated for safety, efficacy, side-effects, and dose related toxicity through clinical trials (CDC). Vaccination studies begin in small groups during phase one trials and must be evaluated against a control group in phase three trials involving hundreds to thousands of people (CDC). After extensive research and testing, FDA licensed vaccine must be tested by manufactures before being released (CDC). All testing is reviewed by the FDA prior to release (CDC). In addition the FDA regularly inspects the facilities responsible for manufacturing and testing the vaccines (CDC).
Although vaccines are carefully monitored for safety, adverse events may occur. These range from moderate to severe. In the case of the Diptheria, Tetanus, and Pertussis (DTP) combination vaccine, common mild adverse events in infants include “fever… and irritability (40-75%), drowsiness (33% to 62%), loss of appetite (20% to 35%), and vomiting (6% to 13%)”(WHO). Severe events are more rare and include high fever in “0.3% of vaccine recipients,” and febrile seizures in “60 per 100,000 doses” according to clinical studies- with fewer occurring in active surveillance studies using data linkage (WHO). Seizures were more common in vaccine recipients with personal or family history of seizure (WHO).
Vaccination is a semi-controlled activation of the immune system and we expect to elicit a immune response. Naturally, our aim is to minimize this immune response to the production of memory cells that will inoculate an individual against a pathogen. However, some local and systemic cytokine signaling will occur, and this will lead to local inflammation and in some cases systemic adverse events like fever. When evaluating vaccine efficacy we must determine if the benefits of long-term immunization outweigh these acute responses.
Center for Disease Control and Prevention (CDC). The Journey of Your Child’s Vaccine. December 28, 2015. http://www.cdc.gov/vaccines/parents/infographics/journey-of-child-vaccine.html
World Health Organization (WHO). Information Sheet Observed Rate of Vaccine Reactions Diphtheria, Pertussis, Tetanus Vaccines. May 2014. http://www.who.int/vaccine_safety/initiative/tools/vaccinfosheets/en/
I agree that the literature has repeatedly shown benefits that have immensely outweighed the cons of most types of vaccination. However, I still feel it is worth investigating into the factors that perhaps lead to one to be more susceptible to an adverse reaction and how to mitigate such reactions, if not only to protect the mentioned 0.03%, but also to elucidate more about the mechanisms by which activated immunity can be controlled in a balanced way.
For the current required vaccinations, I am firmly of the belief that the benefits far outweigh the risks when it comes to vaccination. Anti-vaxxers like to focus on that 0.3%, on the 60/100,000 as evidence that vaccinations should not be given. But, there is a 0.007% chance of death after having a colonoscopy (0.03% when factoring all reported deaths, but those directly attributable to colonoscopy amounted to 0.007%) [1]. That doesn't mean that people should stop getting colonoscopies. Simply existing comes with risk, and while it is truly unfortunate for those that suffer the *extremely rare* side affects of a vaccine, procedure, or treatment, we have to turn back to statistics and ask if the health of the population is significantly better than before.
[1] http://www.asge.org/assets/0/71542/71544/56321364-c4d8-4742-8158-55b6bef2a568.pdf