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COVID 19 Vaccination: What We Know Now


As the COVID-19 pandemic rages on in the U.S., the numbers are simply staggering: Over 18.7 million cases and 330,000 deaths, both the highest numbers of any country in the world by far.


But there is hope on the horizon.


The Pfizer COVID-19 vaccine was approved by the Food and Drug Administration for use in the U.S. on December 11. The Moderna COVID-19 vaccine was approved on December 18. Vaccination of at-risk individuals in the health care work force has already begun. It was anticipated that up to 10 million Americans will be able to receive their initial vaccine doses before the end of 2020, with the vast majority of Americans expected to have access to a vaccine by the spring of 2021 (https://www.sciencenews.org/article/covid-19-coronavirus-moderna-vaccine-fda-approval ). As of December 24, a vaccination tracker on Bloomberg News estimated that 1.23 million Americans had received the vaccine (https://www.bloomberg.com/graphics/covid-vaccine-tracker-global-distribution/ ).


Although the vaccine rollout has been unprecedented in its speed, it has not been without controversy. Many individuals are wary of the new vaccines, citing the rapidity of development and attendant safety concerns. Internet-based social media chatter has raised plenty of doubt about the vaccine, although a recent poll by the Kaiser Family Foundation revealed that 71% of Americans are now willing to take a free and safe COVID-19 vaccine, up from 63% three months ago (https://thehill.com/policy/healthcare/530333-poll-finds-increasing-number-of-americans-including-black-people-would-take).


It is estimated that so-called “herd immunity,” when the virus begins to decrease its circulation in the community, is reached when the percentage of the population which has immunity is ~70%. Although there are over 18 million confirmed COVID-19 cases in the U.S., the actual number of cases is estimated to be much higher—up to 8 times higher, in fact.


So what is fact and what is fiction? Let’s take a look at the data.


How the Pfizer and Moderna Vaccines Were Developed

Both the Pfizer and Moderna vaccines are so-called messenger RNA (mRNA) vaccines. This is a novel type of vaccine which has never previously been approved by the FDA.


Traditional vaccines may use either a weakened version of a virus (a so-called “live attenuated vaccine”), a dead or “killed” version of a virus (inactivated vaccine) or a lab-generated protein to cause an immune response in the vaccinated person.


Live attenuated vaccines can cause infection in some immunocompromised individuals. Examples of live attenuated vaccines include measles, mumps, rubella, smallpox and chickenpox.


Inactivated or “killed” vaccines cannot cause infection, although they can result in allergic reactions in recipients due to the culture medium the viral organisms are grown in before being inactivated. Inactivated virus vaccines can be made up of the whole virus (such as with polio, hepatitis A and rabies) or a protein subunit of a virus (such as with influenza, human papillomavirus, hepatitis B or anthrax). The vaccines for tetanus and diphtheria are specifically directed at toxins produced by those organisms.


Lab-generated vaccines include vaccines developed by recombinant DNA technology, in which a segment of viral DNA is inserted into a yeast cell which then produces the pure viral protein. Some hepatitis B, influenza and human papilloma virus (HPV) vaccines are produced this way (https://www.cdc.gov/vaccines/pubs/pinkbook/downloads/prinvac.pdf ).


mRNA vaccines, such as the Pfizer and Moderna COVID-19 vaccines, use an artificially synthesized strand of messenger RNA wrapped in a protective fat layer to keep in from disintegrating. The mRNA strand contains molecular instructions to construct a version of the so-called “spike protein” which resides on the outside of SARS CoV-2, the virus which causes COVID-19. That results in an immune response by the vaccine recipient’s body which causes both antibody production and cell-based immunity. This is a new sort of vaccine which has not ever been utilized previously—and is a product of the scientific community’s increasing prowess in biotechnology (https://www.washingtonpost.com/world/europe/coronavirus-vaccine-race-messenger-rna-imperial-college/2020/07/05/6565b2d0-ba2e-11ea-97c1-6cf116ffe26c_story.html ).

Pfizer and Moderna Vaccine Efficacy

Both the Pfizer and the Moderna vaccines were quite effective at conferring protection against COVID-19—around 95% protective after the second dose of each vaccine.



These two diagrams show the relative efficiacies of the two EUA-approved vaccines over time. The treatment group in either case is the lower curve (blue with Pfizer; red with Moderna). The differences between the vaccinated persons and those given placebo vaccine injections in both studies are striking.


The Pfizer vaccine clinical trial used two groups of 21,000 persons each. The persons in the group were randomized to receive either the vaccine or a placebo (which is like an injection of salt water). There were two vaccine doses in the trial, given three weeks apart. The recipients and the persons administering the vaccine were blinded as to who received each injection. The Pfizer vaccine was 95% effective at preventing COVID-19 infection after both doses had been administered. Among the 20,000 trial participants who received both doses of the vaccine, only 8 persons contracted COVID-19, and only one became seriously ill. By contrast, 162 persons in the 20,000-person placebo arm contracted the disease, and 9 of those developed serious illness.


The Moderna vaccine clinical trial looked at 15,000 participants in each arm of the trial (placebo and treatment phases). The vaccine had a 94.1% efficacy overall. Once again, a second dose of vaccine, administered 4 weeks after the first, was needed for maximum efficacy.


A CNN comparison between the two approved vaccines can be reviewed here:


Vaccine Side Effects

The side effects for both vaccines in the clinical trials were mild and tended to resolve after the second day following the injection. The most common side effects were injection site soreness, fatigue, headache, muscle aches, joint aches and chills. A total of 15% had fever. Localized lymph node swelling was seen in 14%. No serious or life-threatening side effects were reported. Symptoms tended to be slightly worse after the second injection (https://www.theatlantic.com/health/archive/2020/12/what-expect-when-you-get-covid-19-vaccine/617428/ ).


After vaccine rollout, there have been a few isolated cases of serious post-injection allergic reactions documented. All of the patients had a history of prior severe allergic reactions. None of the patients died. However, it has been recommended that anyone who experiences a severe allergic reaction with the first dose of a particular vaccine should not receive the second dose of the vaccine (https://www.theatlantic.com/health/archive/2020/12/coronavirus-vaccine-allergic-reaction/617482/ ).


Vaccine Availability

The Pfizer vaccine poses a unique challenge: It must be kept very, very cold until it is ready to be administered. Typically, it is stored at -70 degrees Celsius (-94F), which is colder than the average winter temperature at the South Pole. This does present some distribution challenges, since many smaller medical facilities and pharmacies don’t have access to freezers with that capacity. Pfizer has developed its own shipping containers which can keep its vaccines at the required temperatures for up to 10 days. Keeping the vaccine that cold for a longer period of time requires a network (the so-called “cold chain”) of airport freezer warehouses, freezer trucks and on-site freezers which may limit its use.

Once thawed for administration, the Pfizer vaccine can be stored in a standard refrigerator for up to five days before it expires.


The Moderna vaccine needs to only be stored at -20 degrees Celsius (-4 F), which is roughly the equivalent of the temperature of a home freezer. Once thawed, it may be kept in a standard refrigerator for up to 30 days before it expires. The lack of the need for a “cold chain” transport system may allow the Moderna vaccine to get into more remote areas not readily accessible to the Pfizer vaccine. A comparison between the Pfizer and Moderna vaccines is reviewed here: https://www.sciencenews.org/article/covid-19-coronavirus-moderna-vaccine-fda-approval ).


The Astra-Zeneca vaccine, which is not yet approved in the U.S., can be transported and stored between 2 and 8 degrees C (36-47 F), which is about the temperature of a home refrigerator. The Johnson and Johnson vaccine, a single-dose vaccine, can be transported at similar temperatures to the Astra-Zeneca vaccine and will likely be available in early 2021 (https://www.verywellhealth.com/johnson-and-johnson-covid-19-vaccine-5093160 ). Both of these vaccines are participants in Operation Warp Speed, the U.S. vaccine development program, and are likely to receive FDA approval at some point during 2021.


Vaccine Questions

There have been numerous questions about the vaccine which have come up as it is being rolled out. Obviously, in a situation as complex and as fluid as this one, numerous questions arise daily. Here are a few we have seen:


Should I be vaccinated if I have already had COVID-19? It appears that the vaccine confers better immunity to COVID 19 than many mild naturally-occurring infections of the virus. The antibody response is certainly not predictable on a case-by-case basis, and there have been documented cases of people being infected with COVID-19 twice. For this reason, it is recommended that persons who have had prior COVID 19 infections be vaccinated.


Can I take the COVID-1 9 vaccine if I am immunocompromised? Neither the Pfizer nor the Moderna vaccine is a live virus vaccine, so there is no risk of infection with either vaccine. As such, there is no reason why an immunocompromised person cannot receive the vaccine. Given that immunocompromised persons are at higher risk for COVID-19 complications, it is actually strongly recommended that they receive the vaccine (https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-with-medical-conditions.html ).


I have an egg protein allergy. Can I receive the COVID-19 vaccine? Unlike many live virus and killed virus vaccines, the COVID-19 vaccine is not “grown” in any culture medium (such as the egg-based viral cultures used in some vaccines). As such, there is no risk in taking these vaccines if one has an egg protein allergy.


I am not a health care worker. When can I expect to be able to be vaccinated? There is a multi-tiered approach to vaccine candidacy. The nation’s 18 million health care workers and ~2 million nursing home residents have been earmarked to get the vaccines first. Persons with essential jobs that place them at increased risk for exposure, such as teachers and food workers, as well as persons over the age of 74 are in the next tier. Persons with underlying medical conditions will likely be next. Younger, otherwise healthy persons will be vaccinated later, perhaps in the early spring.


It is hoped that everyone in the U.S. who wants to be vaccinated for COVID 19 will be able to receive vaccination by June 2021.


The Washington Post has a tool which allows one to assess one’s place in the vaccine line on a state-by-state basis. Georgia, for example, has about 470,000 health care workers and 87,000 nursing home residents. The state has received about 85,000 doses of vaccine as of this writing and anticipates receiving 470,000 doses by the end of the year 2020—enough to vaccinate 4.4% of the state’s population https://www.washingtonpost.com/graphics/2020/health/covid-vaccine-states-distribution-doses/).


Can children receive the COVID-19 vaccine? Neither the Pfizer nor the Moderna vaccine has been tested in children, although Pfizer has begun trials in children as young as age 12 and has already been approved for use in children as young as age 16. The Moderna vaccine cannot be given to anyone under the age of 18.


How much will the vaccines cost? The vaccines themselves are free to anyone who wants them, although some companies may charge a small fee for doing the injection.


Can I decide which vaccine I want to take? At least initially, no. The vaccines are likely to be in short supply at first, and their efficacies and side effect profiles are similar, so the current recommendation is that one receive whichever vaccine is available. That may change over time, however, as more vaccines become available.


Will I still need to wear a mask and socially distance after I am vaccinated? For a while, yes. It will take several months for the vaccine to be widely distributed enough in the population to stop the virus from spreading. For that reason, continued social distancing and mask-wearing will need to be practiced for some time yet—perhaps even through the remainder of 2021.


I’ve had Gullian-Barre syndrome. Can I get the vaccine? Gullian-Barre syndrome is a rare ascending motor paralysis which was reported with the Swine flu vaccine in 1976. There have been no cases of this syndrome with either approved COVID-19 vaccine, so persons with a prior history of Guillain-Barre are not excluded from vaccination.


Will the vaccines work against the new COVID 19 strain seen in England? It was recently reported that a new variant of SARS CoV-2, the virus which causes COVID-19, was spreading rapidly through Great Britain. This variant, known as B.1.1.7, is estimated to be as much as 50% more transmissible than other variants currently in circulation (https://www.economist.com/science-and-technology/2020/12/23/evidence-mounts-a-new-coronavirus-variant-is-more-transmissible ). More than 50 countries, including the U.S., have restricted arrivals from Britain as a result. Thankfully, hospital admissions data at this point do not seem to indicate that this new strain causes more severe disease than other strains. Moreover, the 23 new genetic mutations identified in the B.1.1.7 variant do not affect the part of the spike protein used for generating vaccine-related immunity. There is therefore broad consensus that the vaccines currently in use against SARs CoV-2 will be effective against this new variant.


COVID vaccine myths and falsehoods

There have been a number of myths and falsehoods circulated on the Internet about the COVID-19 vaccines. Unfortunately, these misconceptions have hindered acceptance of the vaccine among certain groups of individuals.


Myth 1: The vaccines were rushed. This is simply not true. While the rapid development of vaccines for COVID-19 set a record by several years, the vaccines took advantage of a combination of several important variables. First, pre-existing vaccine research on the related SARS virus gave researchers an edge. Second, the SARS CoV-2 viral genome (the virus which causes COVID-19) was sequenced very early. The first one was published by Chinese researchers on January 10, 2020, even before COVID had spread out of China (https://wwwnc.cdc.gov/eid/article/26/10/20-1800_article ). Third, advance funding by the governments of the U.S. and other nations allowed pharmaceutical companies to develop the vaccine without significant fiscal risk. Fourth, the presence of an active pandemic gave researchers plenty of readily-available test subjects for the clinical trials, allowing for very rapid enrollment of patients. Finally, the evolution of new biotechnology techniques allowed more rapid progress than had previously been possible during earlier vaccine development efforts. We’re simply better at biotech than we used to be. The resulting science is impressive. The full set of FDA documents supporting vaccine development are publicly available for review. Here is a link to the Moderna vaccine documentation, for example: https://www.fda.gov/media/144434/download


Myth 2: The vaccines contain microchips which can be used for tracking individuals. This myth began as anti-vaccination groups spread memes on social media about Bill Gates, the Microsoft founder who has donated millions to help spur vaccine development and administration in developing countries worldwide. The common theme is that Gates wants the microchips inserted into individuals so that he can somehow “track” them. This allegation is simply false—and, in fact, fails the application of simple logic. The vaccines themselves are very small in volume (0.3 mL for Pfizer; 0.5 mL for Moderna), and there is no “tracking microchip” in the world small enough to be injected in this volume of liquid through the tiny needles which are used in vaccination. In addition, if a subversive goal of vaccination involved insertion of “tracking microchips,” why use a vaccine which is voluntary? Why not put it in something universal—like drinking water, for example?


Of course the most obvious logic-based refutation is this one: Over 96% of the U.S. population now carries a cellular phone, each of which has GPS-based tracking software built right into it. The technology to track us via our cell phones already exists. So if someone really wants to track you, guess what? They probably already are.


The Gates Foundation has indeed donated over 300 million to aid in COVID-19 vaccination, as it has for numerous other vaccines. But there are no microchips in the COVID-19 vaccine, or in any other vaccine. That’s just a whole bunch of malarkey (https://www.businessinsider.com/coronavirus-vaccine-pfizer-moderna-doesnt-contain-a-microchip-2020-12 ).


Myth 3: I can get COVID-19 from the vaccine. This is actually quite impossible. As stated earlier, the Pfizer and Moderna vaccines are mRNA vaccines. They are not live virus vaccines. As such, there is no risk of acquiring COVID 19 from vaccination with these mRNA vaccines. The Oxford-Astra Zeneca vaccine does use a weakened chimpanzee adenovirus as a vector, and the Johnson and Johnson vaccine similarly uses a weakened adenovirus with recombinant DNA technology to induce an immune response, but even these vaccines are also highly unlikely to cause any sort of infection. Both the Astra-Zeneca vaccine and the Johnson and Johnson vaccine are likely to be approved in the U.S. sometime in the first half of 2021.


The Chinese vaccine-makers Sinopharm and Sinovac use inactivated or “killed” versions of SARS CoV-2, but even these vaccines are not capable of causing infection with COVID-19. It is unlikely that the Chinese vaccines will ever be marketed in the U.S.


Myth 4: The COVID-19 vaccines will alter my DNA. This is simply impossible. The mRNA vaccines work in the cytoplasm of the cell. The strands of mRNA used never enter the nucleus of the cell and are destroyed in the process of protein synthesis. Former US Centers for Disease Control and Prevention director Dr. Tom Frieden came up with this analogy:


"An mRNA vaccine doesn't actually contain the virus itself. Think of it as an email sent to your immune system that shows what the virus looks like, instructions to kill it, and then—like a Snapchat message—it disappears. Amazing technology," Frieden recently tweeted.


The idea that such a vaccine can “alter one’s DNA” is science fiction. Cigarette smoking and ambient sun exposure are both more likely to cause DNA alteration than the COVID vaccines.


Myth 5: People who get the COVID-19 vaccines frequently get Bell’s Palsy. Bell’s palsy, a disease which temporarily causes unilateral facial muscle paralysis by affecting the facial nerve, was reported in 4 out of 22,000 vaccine recipients during the Pfizer trial. This is consistent with the number of people who develop Bell’s palsy in the general population and in fact may have nothing to do with the vaccine.


Myth 6: The COVID-19 vaccine will make you infertile. This is completely false. There are no data anywhere which imply that COVID 19 vaccination causes infertility. This is a baseless internet rumor propagated by anti-vaccination activists. In fact, due to the large number of ACE 2 receptors in testicular tissue, there has been some speculation that COVID 19 infection itself may negatively impact male fertility (https://www.thelancet.com/action/showPdf?pii=S2589-5370%2820%2930348-5 ).


Myth 7: The current COVID-19 vaccines use aborted fetal tissue. This is false. The Pfizer and Moderna vaccines are synthesized in a laboratory. No fetal tissues were used in their development.

This rumor got its start because five of the vaccine candidates being tested utilize human fetally-derived cell lines to grow the adenoviruses which produce the vaccine products, including the Astra-Zeneca and Johnson and Johnson vaccines. However, even in these vaccine types, no fetal tissues are injected into recipients. And mRNA vaccines like the approved Moderna and Pfizer vaccines are not produced in that fashion in any case (https://www.sciencemag.org/news/2020/06/abortion-opponents-protest-covid-19-vaccines-use-fetal-cells ).


Myth 8: The government is about to make COVID-19 administration mandatory. No they’re not. There’s been no published guideline anywhere which mandates COVID-19 vaccination. Moreover, employers and schools cannot presently mandate COVID-19 vaccination as the vaccines are being given under the FDA’s Emergency Use Authorization program.


Final Thoughts

As we move from 2020 into 2021, the availability of COVID 19 vaccination is a glimmer of hope in an otherwise bleak winter pandemic season. Worldwide, the COVID 19 pandemic has defined this past year in every respect. COVID 19 has been found on every continent, including Antarctica, and in every nation in the world. The viral illness has rocked the world’s economy and has caused over 80 million documented cases of illness and 1.75 million deaths worldwide so far this year (https://www.worldometers.info/coronavirus/#countries ).


The United States has been disproportionately impacted by the virus, with the highest numbers of cases and deaths of any nation. The end result has been an alteration in almost every social thing we do, from athletic contests and church services to seminal life events like weddings, funerals and family gatherings.

It has been, without question, a very stressful year.


As a health care professional, I have seen firsthand the impact of COVID-19 on individual patients and on the health care system as a whole. My medical practice essentially shut down for all elective procedures for two months last spring in order to conserve resources for the hospitals. I’ve seen COVID patients survive and I’ve seen them die. Medical colleagues have been infected and become ill, some more seriously than others. The pandemic has changed many of the things I do in practice.


And yet I am hopeful.


The state of Georgia has begun immunizing health care workers and residents of nursing homes. The Georgia Department of Public Health has outlined its vaccination game plan here: https://dph.georgia.gov/covid-vaccine


I received my first dose of the Pfizer COVID 19 vaccine last week. I was grateful for the opportunity (I had no side effects at all, by the way). It has been heartening to see my medical colleagues’ selfless dedication to the care of others—and to beating this pandemic. It is my fervent hope that the development of effective vaccines will mark the beginning of the end of one of the darkest chapters in the history of American public health. In the interim, we must all remain vigilant, wear masks in public places, maintain social distancing—and pray for better days ahead.


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