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A vaccine can help prevent the spread of COVID-19 and reduce the associated morbidity and mortality from transmission of the disease in vaccinated individuals. Pfizer and Moderna vaccines are available and induce immunity in greater than 94% of individuals. The Pfizer and Moderna vaccines are both nucleoside-modified messenger RNA (modRNA) vaccines. The two vaccines are the first of a new type of vaccine based on messenger RNA (mRNA). Instead of injecting a weakened or killed virus into the body, mRNA vaccines teach cells how to make a protein—or even just a piece of a protein—that triggers an immune response.

Johnson and Johnson's single-dose Covid-19 vaccine works safely according to the U.S. Food and Drug Administration and is also available. The vaccine was 66.1% effective in preventing moderate to severe disease.

Why The Mask Reversal? What do we Know About "Breakthrough Infections"?

According to the CDC, as of July 19, 2021 a total of 4,072 vaccinated Americans had been hospitalized with symptomatic breakthrough infections, out of more than 161 million vaccinated for a breakthrough hospitalization rate of less than 0.003 percent. Overall 849 have died of covid-19, so the death rate from those breakthrough infections is 0.0005 percent. For comparison your chance of dying from a lightning strike is .0007 percent, and your chance of dying from the seasonal flu is 0.1 percent. What this means is that for otherwise healthy vaccinated people — and those who have natural immunity from previous infection — the chance of dying of covid-19 is close to zero.

The same is true for unvaccinated children. As Johns Hopkins University professor Marty Makary points out in the Wall Street Journal, CDC data show that of the more than 600,000 Americans who died with a covid diagnosis code in their record, just 335 were children under 18 — and the CDC has no idea whether they had a preexisting condition and whether their covid diagnosis was incidental or causal. 

Moderna’s COVID-19 Vaccine - Active Against Variants

Moderna’s vaccine mRNA-1273, was found to elicit neutralizing antibody activity in all study participants, according to initial trial results published in The New England Journal of Medicine and has been approved for use by the Food and Drug Administration. (1) For more information visit

An update released shows that protection from the COVID-19 vaccine candidate remained elevated 3 months after delivery of the second dose, study. Alicia T. Widge, MD, an allergist-immunologist at the National Institute of Allergy and Infectious Diseases, and colleagues reported on 34 healthy adult participants in three separate age groups who received two injections of the vaccine, called mRNA-1273, at a dose of 100 μg.

According to Widge and colleagues, the vaccine “produced high levels of binding and neutralizing antibodies that declined slightly over time, as expected, but they remained elevated in all participants 3 months after the booster vaccination."

Research suggests that vaccination produces neutralizing titers against all key emerging variants evaluated thus far including those identified in the UK (B.1.1.7 variant) and the Republic of South Africa (B.1.351 variant).8

Pfizer Vaccine Appears Effective Against New SARS-CoV-2 Strains

The COVID-19 vaccine developed by Pfizer and BioNTech appears to be effective against emerging SARS-CoV-2 variants that spread more easily than other strains according to early data from Pfizer and the University of Texas.

The new variants appear to infect people more easily but thus far there is no evidence that they are more deadly. The coronavirus is an RNA virus, and they typically develop mutations over time. Doctors believe that the current vaccines should be effective however as the virus continues to mutate this could change. It will be important to monitor COVID-19 infections that occur in individuals who have previously had the disease and those who develop disease who are vaccinated.7,8

Pfizer-BioNTech: Update on COVID-19 Booster Shot

According to Moderna and Pfizer-BioNTech COVID-19 vaccine administration of a “booster” vaccine 6 months after the primary 2-dose series will be necessary. The Pfizer vaccine elicits high neutralization titers against both the wild type and the Beta variant (B.1.351) Corona Virus as does Moderna which also has activity against the Delta variant. Moreover, an updated version of the Pfizer-BioNTech COVID-19 vaccine that targets the full spike protein of the Delta variant is also in development. 

The Centers for Disease Control and Prevention and the FDA released a joint statement July 8th stating that, “Americans who have been fully vaccinated do not need a booster shot at this time.” 15,16

Israel however has already announced the country would give booster doses to its elderly population and Pfizer and BioNTech have announced that they plan to seek authorization for their COVID-19 “booster” vaccination. Their data shows vaccine effectiveness diminishes over time, and that a booster “may be needed within six to 12 months after full vaccination.” 

So who’s right? and why wouldn't you develop the booster program as early as possible just to be cautious? This is especially true for immunocompromised individuals like cancer patients who are most at risk of dying from COIVD-19? 

A subsequent study of COVID vaccine boosters suggests Moderna or Pfizer works best and both were approved by the FDA in October 2021 - reversing the previous position.

Additional Dose and Booster Shot FAQ

Is an additional dose the same as a booster shot?

No. An additional dose is different from a booster dose, immunocompromised individuals, may not develop the same immune response after vaccination so an additional dose is recommended to help them build the same level of immunity as people who are not immunocompromised.

Who should get a booster shot of COVID-19 vaccine?

The Centers for Disease Control has recommended everyone 16 years and older receive a booster shot.

  • For Moderna and Pfizer-BioNTech COVID-19 vaccines, a single COVID-19 vaccine booster dose is recommended 6 months after completion of an mRNA primary series. The Moderna booster dose is a smaller 50 microgram dose.
  • For Janssen (Johnson & Johnson) COVID-19 vaccine, a single COVID-19 vaccine booster dose is recommended for people aged 18 years and older, 2 months after receipt of the initial Johnson & Johnson dose, under the FDA’s Emergency Use Authorization.

Who should get an additional dose of vaccine?

Currently, individuals with moderately to severely compromised immune systems are recommended for an additional dose of COVID-19 vaccine if they previously received a two-dose primary series of either the Pfizer BioNTech or Moderna COVID-19 vaccines. More information here: COVID-19 Vaccines for Moderately to Severely Immunocompromised People | CDC

Can I get any type of COVID-19 vaccine for the additional dose or booster dose?

FDA Authorizes Moderna, Janssen COVID-19 Booster Shots, Allows for Mix and Match

The Food and Drug Administration (FDA) has amended the Emergency Use Authorizations (EUA) for the Moderna COVID-19 vaccine and the Janssen COVID-19 vaccine to include use of a booster dose.

For the Moderna COVID-19 vaccine, a single booster dose at the 50µg dose level (0.25mL) may be administered at least 6 months after completion of the primary series to individuals 65 years of age and older, as well as to people 18 to 64 years old at high risk of severe COVID-19 or to those with frequent institutional or occupational exposure to SARS-CoV-2. Additional information about the booster dose can be found in the updated Moderna COVID-19 EUA fact sheet.

For the Janssen COVID-19 vaccine, a single booster dose may be administered at least 2 months after completion of the single-dose primary regimen in individuals 18 years of age and older. The Janssen COVID-19 vaccine booster dose level is the same as the one administered for the primary vaccination (0.5mL). The updated Janssen COVID-19 EUA fact sheet can be found here.

The Agency has also authorized the use of a heterologous (or “mix and match”) booster dose for all currently authorized and approved COVID-19 vaccines following the completion of primary vaccination. After a review of available data, the FDA found that the benefits of a single heterologous booster dose outweighed the known or potential risks.18-20

Johnson & Johnson

The Johnson & Johnson vaccine candidate unlike Pfizer and Moderna, uses a human adenovirus that has been modified to no longer replicated in humans and cannot cause disease. The vaccine is reported to be 66% effective in preventing moderate to severe COVID-19 at 28 days post-vaccination. The vaccine is reported to be 85% effective in preventing severe/critical COVID-19. Moreover, the vaccine demonstrated complete protection against COVID-19 related hospitalization and death at 28 days post vaccination. Onset of protection was observed as early as day 14 and there were initially no reported COVID-19-related deaths in vaccinated individuals. Vaccine roll out however was halted due to concerns about blot clots occurring in several women of child bearing age, including one fatality.9,10 

On Friday, April 23, 2021 the US FDA Advisory Committee on Immunization Practices voted to recommend resuming the use of the Johnson& Johnson COVID-19 vaccine based on their assessment that the benefits clearly outweigh the risks. There were 6 reported cases of blood clots including one fatality in women between age 18 and 48 in the first 6.8 million vaccine doses administered.

Johnson & Johnson also reported that a booster dose of its COVID-19 vaccine generated a ninefold increase in antibodies among clinical trial participants compared with levels seen 28 days after the first shot supporting the use of a booster shot in people who previously received the single-dose regimen. The studies demonstrated significant increases in binding antibody responses among participants aged 18 to 55 years, as well as among those aged 65 years or older who received a lower booster dose, the company said.

How Long Does Immunity Last?

The answer to this question has long been awaited and the early evidence looks good. Top line data from the phase 3 study evaluating the Pfizer-BioNTech COVID-19 vaccine released in April 2021 shows that it is highly effective beyond 6 months after the second dose - vaccine efficacy was observed to be 91.3%.  The vaccine was 100% effective at preventing severe COVID-19 disease and 100% effective in preventing the COVID-19 B.1.351 South Africa variant.10

Antibodies elicited by the Moderna COVID-19 vaccine also persisted through 6 months after the second dose, according to new data published in The New England Journal of Medicine.11

Single dose vaccination with Pfizer was found to be 63% effective in residents of nursing homes suggesting the importance of getting both vaccine doses.12

What About Children?

The Food and Drug Administration expanded the Emergency Use Authorization for the Pfizer-BioNTech COVID-19 Vaccine to include adolescents 12 to 15 years of age. Previously, the vaccine had only been authorized to prevent COVID-19 in patients 16 years of age and older.13

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How Nurses Can Promote Healthy Lifestyles for Their Patients

Nurses are undoubtedly an influential force among patients, probably because of their close and frequent contact with patients and wide awareness of population-specific health issues.

The safety of the vaccine in this patient population was based on data from 2260 adolescent participants enrolled in an ongoing randomized, placebo-controlled study in the United States. Participants were randomly assigned to receive either the vaccine (n=1131) or placebo (n=1129) and more than half were followed for at least 2 months following the second dose.

The most common adverse reactions reported in the trial included injection site pain, tiredness, headache, chills, muscle pain, fever, and joint pain. These side effects typically lasted 1 to 3 days and occurred more frequently following the second dose.

As for effectiveness, analysis of immunogenicity data showed that immune responses to the vaccine in the adolescent group (n=190) were non inferior to those observed in older participants (16 to 25 years; n=170). Additionally, a review of COVID-19 cases that occurred 7 days after the second dose among 12 to 15 year olds without evidence of prior SARS-CoV-2 infection demonstrated that the vaccine was 100% effective in preventing COVID-19. No cases occurred among the 1005 participants who received the vaccine, while 16 were reported among the 978 placebo recipients.

While vaccinating children can help contribute to developing herd immunity reports suggest that children without other health conditions have almost zero risk of developing significant complications from COVID-19 infection. The UK reported that over the last year children were nearly 5x more likely to die from suicide than COVID and similar data exists in the US and Doctors from Johns Hopkins have reported a mortality rate of zero among children without a pre-existing medical condition.

Israeli researchers found that one dose of the Pfizer vaccine, instead of the normal two, was 100% effective in children ages 12 to 15 - .this could have significant implications for achieving broad immunity in adolescents while reducing the risk of heart complications, which have been clustered around the second dose

What is known about the risk of myocarditis and COVID vaccination?

A risk of myocarditis and pericarditis following the Pfizer and Moderna vaccine has been reported.

Myocarditis is characterized as inflammation of the heart muscle. Pericarditis is inflammation of the tissue surrounding the heart. Symptoms may include chest pain, shortness of breath and heart palpitations. Individuals developing myocarditis are typically under age 30 and symptoms appear 4-8 days after vaccination, more commonly after the second dose of the mRNA vaccine.

Israeli doctors reported that the incidence of myocarditis was 2.1 per 100,000 vaccinated individuals and was most common in males age 16-29 following the Pfizer vaccine.16

The CDC says 323 cases of heart inflammation have been confirmed after the second dose of the Pfizer or Moderna vaccine. More than 250 possible cases are still being investigated. According to the voluntary, self-reporting Vaccine Adverse Event Reporting System, the rate of myocarditis among adolescents 12 through 17 who received a COVID-19 vaccine was 1.8 per 100,000. For boys, it was 3.2 per 100,000.

For every 1 million second doses administered, Moderna vaccine recipients had 10.7 additional cases of myocarditis and pericarditis over people who got Pfizer, according to the study. The difference was even higher in men, who experienced 21.9 excess myocarditis and pericarditis cases with Moderna’s second shot, while women had 1.6 additional cases. Higher rates of myocarditis have not been reported in individuals receiving the single-dose Johnson & Johnson vaccine, which does not use the mRNA technology.21

Vaccination may also prevent long-term symptoms, and a hyper-inflammatory condition called MIS-C, which strikes an estimated 1 of every 3,200 children infected with SARS-CoV-2 (SN: 5/12/20).

For more information visit the CDC and VAERS website.

COVID-19 Vaccination Does Not Increase Deep Vein Thrombosis 

Vaccination against COVID-19 does not appear to increase the risk of deep vein thrombosis (DVT), according to research presented at the 2021 American Society of Hematology (ASH) Annual Meeting. Researchers evaluated clinical data from 382,527 patients at least 18 years of age vaccinated against COVID-19 between November 2020 and June 2021; 64% had received the Pfizer vaccine, while 32% had received the Moderna vaccine, and 4% received the Janssen vaccine. The incidence of DVT was found to be similar to the expected historical rate.17

Other Vaccine Development Summary from Haymarket Media

  • Several other vaccines using a variety of platform technologies are in the pipeline. A Novavax protein subunit vaccine has been designated for fast-track review by the FDA. Phase 3 trials are under way in the UK and will start soon in the US and Mexico. Novavax is also working on a combination flu/COVID-19 vaccine for use after the pandemic.
  • Sanofi and GlaxoSmithKline have a recombinant protein-based vaccine that will be ready to seek regulatory review in 2021. Sanofi is also partnering with Translate Bio on an mRNA vaccine.
  • Manufacturers are seeking approval in many countries - as well asemergency use listing from the World Health Organization - that would make the vaccines available in low-income countries. Globally, the WHO notes, there are 48 COVID-19 vaccine candidates undergoing clinical evaluation.

Oxford-AstraZeneca - ChAdOx1 nCoV-19 Vaccine 

Interim results from the phase 1/2 COV00 “University of Oxford” clinical trial evaluating the vaccine candidate ChAdOx1 nCoV-19 (AZD1222) with AstraZeneca showed that vaccination led to strong immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in all evaluated participants.6

Initial trial results demonstrated that vaccination led to a 4-fold increase in antibodies to SARS-CoV-2 one month after vaccination and a T-cell response in all participants that peaked by day 14 and was maintained 2 months after vaccination. The vaccine a elicited neutralizing antibody responses against SARS-CoV-2 in 91% of study participants 1 month after vaccination and in 100% of participants after receiving a second dose.  AstraZeneca reported that its COVID-19 vaccine had a 79% efficacy rate at preventing symptomatic COVID and was 100% effective in stopping severe disease and hospitalization across all ages including people over 65.  The European Medicines Agency concluded after an investigation that the vaccine did not raise the overall risk of blood clots.

The AstraZeneca vaccine is different than the Moderna and Pfizer vaccines. It is a “viral vector” vaccine. The vaccine uses a harmless cold virus that normally infects chimpanzees to carry the COVID spike protein’s genetic material into the body, which produces some harmless protein that primes the immune system to react to the real COVID virus.15

One question that could confound vaccine development is whether the presence, or absence, of antibodies to the novel coronavirus can reliably determine immunity. A viral infection triggers a two-fold immune response that includes production of immune cells that target the virus. This includes a B-cell antibody response that can recognize a virus and lock onto it, preventing its entry into cells and a cellular T cell response that can kill both the invading virus directly and the cells it has infected.

Vaccine candidates against COVID-19 currently in the works aim to generate antibody and T cell responses, and recent findings highlight the importance of understanding the T cell response seen in human clinical trials. An optimal vaccine may need to induce both an antibody and a T cell response. There are also questions about exactly which combination of immune-system cells will result in significant protection.

Blood tests that look for antibodies are used to estimate how many people have been infected with the virus even if they never showed symptoms. But scientists still do not know how antibody levels correlate to exposure to the virus or how long they may last. Regularly measured antibodies against the virus, typically IgG, often disappear, especially in asymptomatic individuals. Evidence is increasing that some people exposed to the virus have a transient short-lived antibody response or a T cell response in spite of a minor or absent antibody response.

Some patients that have recovered from COVID-19 infection who tested negative for coronavirus antibodies go on to develop T cells in response to their COVID-19 infection. The key question for current vaccine development is whether the antibody response to the virus is robust and lasts long enough to confer a long-lasting immunity.

T cells may have a more important role in offering protection against COVID-19 than previously thought. One small French study found that six out of eight family members in close contact with relatives who had COVID-19 developed a T cell response but did not test positive for antibodies. (2) A Swedish study in 200 people also found a strong T cell response in asymptomatic individuals following coronavirus infection, regardless of whether they showed an antibody response. (3) Published in Nature this week, 23 SARS recovered patients, infected with betacoronaviruses induced multi-specific and long-lasting T cell immunity. (6)

Taken together these studies suggest that coronavirus infection rates may be much higher than what has been studied using antibody tests alone and effective COVID-19 vaccine may need to prompt T cells to work in addition to producing antibodies in order to achieve vaccine effectiveness.

What if I have a history of allergies?

The American College of Allergy, Asthma, and Immunology released a statement offering guidance to patients with allergies (7) and updated its guidelines regarding the risk for allergic reactions with COVID-19 vaccines on March 25th, 2021.

All individuals planning to be vaccinated should be screened to determine the possible risk for allergic reaction and those with a history of severe allergic reaction to other vaccines should be referred to an allergist/immunologist for further evaluation. Anyone with a severe or immediate allergic reaction of any severity within 4 hours of receiving the first COVID-19 shot should not receive the second dose and may be referred to an allergist/immunologist.

People who have received dermal fillers may develop swelling at or near the site of filled injection following mRNA COVID-19 vaccination; this occurs infrequently and seems to be temporary. Individuals receiving the mRNA COVID-19 vaccine should expect local and systemic post vaccination symptoms, which are expected side effects and not allergic reactions.

  • Allergic reactions to vaccines, in general, are rare with the incidence of anaphylaxis estimated at 1.31 in 1 million doses given.
  • Individuals with common allergies to medications, foods, inhalants, insects, and latex are no more likely than the general public to have an allergic reaction to the Pfizer-BioNTech COVID-19 vaccine. Those patients should be informed of the benefits of the vaccine versus its risks.
  • The Pfizer-BioNTech COVID-19 vaccine should be administered in a health care setting where anaphylaxis can be treated. All individuals must be observed for at least 20-30 minutes after injection to monitor for any adverse reaction. All anaphylactic reactions should be managed immediately, with epinephrine as the first line treatment.
  • The Pfizer-BioNTech COVID-19 vaccine should not be administered to individuals with a known history of a severe allergic reaction to polyethylene glycol as it is a component of this vaccine that is known to cause anaphylaxis.
  • Data related to risk in individuals with a history of allergic reactions to previous vaccinations and/or mast cell activation syndrome/idiopathic anaphylaxis is very limited and evolving. A decision to receive the Pfizer-BioNTech COVID-19 vaccine should be undertaken by you with your physician or other provider administering the vaccine using their professional judgment balancing the benefits and risks associated with taking the vaccine.

What are the vaccine’s side effects?

The most common side effects reported in the clinical trials were pain at the injection site, fatigue, and fever. Serious side effects were rare and other reported side effects of the vaccines include:

  • Injection site pain
  • Tiredness
  • Headache
  • Muscle pain
  • Chills
  • Joint pain
  • Fever
  • Injection site swelling
  • Injection site redness
  • Nausea
  • Feeling unwell
  • Swollen lymph nodes (lymphadenopathy)

Stay Current With COVID Updates .....


  1. An mRNA Vaccine against SARS-CoV-2 — Preliminary Report
  2. Intrafamilial Exposure to SARS-CoV-2 Induces Cellular Immune Response without Seroconversion
  3. Robust T cell immunity in convalescent individuals with asymptomatic or mild COVID-19
  4. Fact Sheet: Explaining Operation Warp Speed
  5. SARS-CoV-2-specific T cell immunity in cases of COVID-19 and SARS, and uninfected controls
  6. Safety and immunogenicity of the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2: a preliminary report of a phase 1/2, single-blind, randomised controlled trial(
  7. BBC. Coronavirus: EU tries to agree response to new UK strain. .
  8. CDC. New variant of the virus that caused COVID-19 detected. .
  9. Moderna COVID-19 vaccine retains neutralizing activity against emerging variants first identified in the UK and the Republic of South Africa. [press release]. Kenilworth, NJ: Merck; January 25, 2021.
  10. Pfizer and BioNTech confirm high efficacy and no serious safety concerns through up to six months following second dose in updated topline analysis of landmark COVID-19 vaccine study. [press release]. New York, NY and Mainz, Germany: Pfizer Inc. and BioNTech SE; April 1, 2021.
  11. Doria-Rose N, Suthar MS, Makowski M, et al. Antibody persistence through 6 months after the second dose of mRNA-1273 vaccine for Covid-19. N Engl J Med. Published online April 6, 2021. doi: 10.1056/NEJMc2103916.


  13. FDA authorizes Pfizer-BioNTech COVID-19 Vaccine for emergency use in adolescents in another important action in fight against pandemic. [press release]. Silver Spring, MD: US Food and Drug Administation. May 10, 2021.

  14. Accessed on August 25, 2021.



  17. Houghton DE, Padmanabhan A, Ashrani AA, et al. Deep vein thrombosis after COVID-19 vaccinations. Presented at ASH 2021; December 11 to 14, 2021. Abstract 291.

  18. FDA takes additional actions on the use of a booster dose for COVID-19 vaccines. News release. October 20, 2021.

  19. Moderna announces FDA authorization of a booster dose of Moderna’s COVID-19 vaccine in the US. October 20, 2021.

  20. Johnson & Johnson COVID-19 vaccine booster shot authorized for emergency use by US FDA. October 20, 2021.