Just a year ago, we were just hearing of this novel virus and what its impact might be; today vaccines are already being administered. Nurses have long been reported as the most trusted professional, so it seems there are multiple reasons for offering this vaccine to the healthcare population first. This approach lays a foundation of trust in consumers so that herd immunity may be more successfully accomplished.
Vaccine Lifecycle is Ongoing
While distribution has already ensued, it's important to keep in mind that understanding how this will work in our bodies, both positively and negatively, is an ongoing study. Basic research initiates any available vaccine, with a stage of discovery and then pre-clinical studies. After the application for the Investigational New Drug is completed and approved, clinical studies follow in three phases of safety and effectiveness, then a Biologics License is approved prior to FDA review. ACIP review (the CDC's committee) follows and in phase four, safety monitoring occurs for serious, unexpected, and adverse events.
This truly did happen at warp speed for the COVID-19 vaccine. Typically this takes 8 to 9 years. The collaborative work between the #governmental agencies and #pharmaceutical industry has been significant, which I am not sure any of us are truly aware, nor do we comprehend the potential consequences of these agreements, deals, investments, or graces. Further, the clinical trials that have been undertaken were exceedingly brief. Watchful surveillance is ongoing, not just for safety, but again for effectiveness.
Pfizer-BioNTech, Moderna, AstraZeneca-Oxford, and Johnson & Johnson-Janssen are those which will likely be available in the United States. The Pfizer-BioNTech was the first available and administered to hospital staff and the elderly, but Moderna became available more recently. The AstraZeneca-Oxford vaccine is primarily a produce of Europe, but is expected to become available in the U.S.
AstraZeneca-Oxford and Johnson & Johnson-Janssen are vector vaccines, while both Pfizer-BioNTech and Moderna are messenger RNA vaccines. Each of these target vulnerable aspects of the Corona virus, which is understood to be the s-protein or that little spike we see sticking out the side of the virus. If our body can recognize this, then it can create the necessary antibodies.
Messenger RNA
The underlying or proposed method of pharmacokinetics for many of our vaccines is that we are provided a weakened genetic material that replicates the #virus or bacteria in any particular vaccine, then in the event we are later exposed, our cells will have a prior knowledge and be able to amp a quick and aggressive attack.
The COVID-19 vaccine is different in that it isn't a weakened virus, but rather a message for our cells in how to recognize the spike protein, which is found on the surface of the SARS-CoV-2 virus. This difference means that those who would become ill from a weakened strain in prior vaccines would not have such response to the COVID-19 vaccine, since mRNA does not enter the cell nucleus. It therefore, could not give someone COVID-19. mRNA is quite vulnerable however, which is why this vaccine needs to remain quite cold.
mRNA vaccines have been studied for influenza, Zika, rabies, and cytomegalovirus (CMV), although its application is new with the COVID-19 vaccine. This approach seems to be the wave of the future.
Emergency Use Criteria for Vaccine Approval
The COVID-19 vaccine has been approved for emergency use authorization (EUA) which the FDA uses to expedite otherwise unapproved products or off-label use of already approved products in a declared emergency involving a chemical, biological, radiological, or nuclear (CBRN) agent. These medical countermeasures can include drugs, devices, or biologics that have the potential to "diagnose, treat, or prevent serious or life-threatening diseases or conditions caused by a CBRN agent when there are no adequate, approved, and available alternatives.
The process for emergency use is fairly defined in that it requires confirmation of public health emergency, whether domestic, military, or public health. A pre-meeting will facilitate a more rapid submission, but ultimately a submission of EUA request is offered to the FDA for review, which is either approved or rejected. The EUA is then terminated once the emergency has been deemed to have resolved.
The request that must be satisfied for the FDA to grant this emergency use authorization includes the presence of a serious or life-threatening condition, which COVID-19 has offered. There has to be evidence of effectiveness and a risk-benefit analysis for safety. No other alternatives must be available to address this life-threatening condition. The FDA expects that the EUA will continue to complete the work towards full FDA approval. This will likely remain in EUA approval throughout 2021.
Normally when one is offered vaccines, they are also offered a VIS sheet that discusses the mechanisms of action of the vaccine, the risk and benefits. Along with the COVID-19 vaccine, one should get a fact sheet specific to the whether the vaccine is Pfizer-BioNTech COVID or Moderna. One difference in the two is that the Pfizer vaccine is available to those as young as 16 years, but Moderna is only approved for those 18 years and older.
Pfizer-BioNTech
Information available on the Pfizer-BioNTech made available to those receiving the vaccine is that it is in fact, a mRNA vaccine designed to prompt the body to recognize the spike protein or s-protein of the virus. The efficacy after the second dose is thought to be 95% with a confidence interval of 90.3% and 97.6%.
This vaccine is offered in two doses, both intramuscularly, three weeks apart. The second dose should be the same vaccine, specifically Pfizer-BioNTech. There is a four-day grace period after that first dose, so between the 17th and 21st day, but outside that window, the first vaccine would be considered invalid. If this window is missed, the recommendation is still to offer the second dose and not to restart the series however. The second dose acts like a booster for the immune response and memory, so it should be administered while the first vaccine is still recognized by the body's immune system.
Avoid receiving another vaccine, such as the flu vaccine, between your COVID-19 vaccine doses and 14 days following the second booster to allow the immune system full opportunity to ramp up a defense to COVID-19.
A common question is about those who have had SARS-CoV-2 infection and whether they are recommended for vaccination, and yes, they currently are with exception of those who are currently sick. Following isolation, one can then obtain the COVID-19 vaccination; however, since reinfection is very uncommon during the first 90 days, one may consider waiting this time. If one has had previously received monoclonal antibodies or convalescent plasma, they are recommended to wait 90 days to avoid interference with vaccine-induced immune response.
Interestingly, the COVID-19 vaccine is being recommended to individuals with or without underlying medical conditions who do not otherwise, have contraindications to vaccination. Thus far, safety profiles are similar between those with and without medical conditions. Individuals with immunocompromising conditions are certainly at greater risk for COVID-19, so they should be vaccinated unless otherwise contraindicated. They should be aware that they may have a diminished response to the vaccine.
There is no data regarding pregnancy or breastfeeding and safety. mRNA is not a live vaccine and does not enter the nucleus of the cell. Keep in mind that women who are pregnant, are immunocompromised, so are at greater risk for poor outcomes from COVID-19, as does her developing child.
Contraindications seem to be largely related to an individual's vulnerability to #anaphylaxis or significant #allergies. Each Pfizer-BioNTech COVID-19 has 30mcg of a nucleoside- modified messenger RNA (modRNA) encoding the viral spike glycoprotein of SARS-CoV-2. This is held in a lipid base and a diluent of sodium chloride. Allergy to any of this would be a contraindication, but each client should be monitored for at least 15 minutes after administration of the vaccine or 30 minutes with any history of anaphylaxis. Providers should be well versed in being able to administer epinephrine. Most reactions will occur in the first two minutes, but like the healthcare worker in Alaska, those reactions weren't seen for almost ten minutes.
Neither the Pfizer nor the Moderna vaccine involved the use of cell lines that originated in fetal tissue taken from the body of an aborted baby at any level of design, development or production, per the Chairmen of the U.S. bishops' doctrine and pro-life committees, on November 24th, 2020.
This particular vaccine, Pfizer, is the one best known currently as it is the one that swept through hospital staff. There have been some challenges with having a second dose available for those who have received the first dose. I have also heard reports of vaccines being wasted because they were brought to room temperature and then staff weren't available to administer the vaccine prior to it becoming unsafe to administer due to temperature changes. More and more hospitals and particularly, nursing homes, are reporting that staff are not accepting the COVID-19 vaccine.
Moderna
The second option currently for COVID-19 vaccine is the Moderna vaccine. It was approved in mid-December for the EUA, so less information is available for the Moderna vaccine. Certainly as these and potential two others become available, clinicians will need to understand storage and handling, preparation of vaccine, administration and emergency response, as well as documentation and how to register the data in to the state program. Education for both clients and practitioners is important, as well as adverse event monitoring.
mRNA vaccines are very fragile and the temperatures they require are a bit challenging. This is also different depending on the vaccine. The Pfizer vaccine needs stored at -70C and the Moderna is about -20C, which is quite different. Of course, these require very specific freezers which must be well monitored. The Moderna is likely to be used more often in remote clinics due to the freezer requirements.
Both are good for six months, frozen, but once refrigerated in preparation for use, they are good for only a month. The Pfizer vaccine is only good for a few hours after it is reconstituted in preparation for administration. As I understand, neither of these vaccines have preservatives but the Pfizer vaccines requires normal saline provided by the company to reconstitute the product.
Vaccine Hesitancy
There are certainly very appropriate reasons to have concern about being among the first who are receiving any new #vaccine. During a pandemic, opinions can range widely and passionately. It is times like these even, that bring to the table discussion about mandation of vaccines. Will this vaccine bring me harm? Will that harm be worse than the risk I currently face with contracting and suffering from COVID-19? How might the vulnerable be at risk by my decision either way? We are somewhat in the unknown.
Thus far, reported adverse events include pain at the injection site, redness, fatigue, myalgias, headache, and fever. Rare reports of severe allergic response have occurred. Certainly the media has reported a few additional cases, which I hesitate to share here without having more credible testimony or evidence.
Vaccine efficacy is some of what plays a part in whether one is willing to take the risk that comes with vaccination, and thus far, the COVID-19 vaccine has demonstrated a 95% efficacy for at least 4 months. Protective antibodies beyond this time are not yet known. Those who are immunocompromised will have earlier decline, as will the elderly. Whatever your concerns or questions, know that they are valid and I am happy to discuss these with you one-on-one to help you decide if the COVID-19 vaccine is right for you and your family.
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