The U.S. Centers for Disease Control and Prevention (CDC) recommends getting a COVID-19 vaccine, stating that, “COVID-19 vaccines are effective at protecting you from getting sick. Based on what we know about COVID-19 vaccines, people who have been fully vaccinated can start to do some things that they had stopped doing because of the pandemic.”1
The CDC advises that after being fully vaccinated, you can visit a private home without a mask if everyone is vaccinated. If you have been fully vaccinated, the agency also states that you can visit a private home without a mask if there is only one family of unvaccinated non-high risk individuals present, and you can travel within the borders of the U.S. without being tested for COVID-19 or quarantining, as well as travel internationally without quarantining and without testing, depending upon your destination.2
Based on the CDC guidelines, a fully vaccinated person should not expect to test positive for COVID-19 if it has been at least two weeks since the second dose of Pfizer or Moderna vaccine or a single dose of the Johnson & Johnson vaccine.
Why then have there been 5,800 confirmed cases of COVID-19 in fully vaccinated persons occurring more than two weeks after vaccination and resulting in almost 400 hospitalizations and 74 deaths?3
Several Hundred Breakthrough COVID-19 Cases in Michigan, Three Deaths
Out of 1.2 million fully vaccinated residents of Washington state, there have been more than 100 breakthrough COVID-19 cases reported in 18 counties resulting in eight hospitalizations and two deaths. The COVID-19 cases occurred in individuals who had received two doses of the mRNA COVID-19 vaccines more than two weeks before they were diagnosed.4
Similar breakthrough COVID-19 cases have been reported in Minnesota, Oregon, Nebraska, Idaho, Michigan and Florida among other states. There were 89 breakthrough cases among healthcare workers reported in Minnesota, four cases in Oregon, 15 cases in Nebraska, 246 cases in Michigan, and 97 cases in Idaho, with Central Florida seeing approximately 38 breakthrough cases.5 6 7 8 9 10 In Michigan, 11 of the vaccinated COVID-19 patients were hospitalized and three of them died.11
In Houston, Texas 142 fully vaccinated individuals tested positive for the virus more than two weeks after their second shot. According to the Houston Health Department, per every 10,000 people vaccinated, there were approximately 2.46 positive cases. Dr. David Persse, the Chief Medical Officer for the city explained, “That is not unexpected. The vaccine is not 100 percent effective.”12
Health Officials Not Surprised About Breakthrough Cases
Other medical experts and health officials say they are not surprised by fully vaccinated individuals testing positive for COVID-19. Dr. Sunil Joshi, president of the Duval County Medical Society Foundation, who is urging everyone to get the vaccine despite the occurrence of breakthrough cases, commented:
So remember, the whole goal for this, from the very beginning, has been to keep people out of the hospital. And so anything positive after the vaccine is not unusual, it can happen.13
In response to the reporting of high numbers of breakthrough cases, Dr. Fauci said:
I think the important thing is to look at what the denominator of vaccinated people is, because it is very likely—and what we’re hearing at least indirectly, and we’re certainly going to be confirming that—that that number of individuals who were breakthrough infections is not at all incompatible with a 90-plus percent vaccine efficacy.14
At the same time, however, Dr. Fauci has stated:
With regard to the breakthrough cases of people who have been vaccinated and ultimately have gotten infection, obviously this is something that we take seriously and follow closely.15
Breakthrough Cases Do Not Involve Viral Shedding
When a fully vaccinated persons tests positive for COVID-19 two weeks post vaccination, it is thought to be from a recent exposure to the virus, not due to vaccine virus infection and shedding. While some live attenuated virus vaccines, such as live oral polio vaccine (OPV) no longer used in the U.S., can cause vaccine strain infection, shedding and transmission (which also occurs during natural infection), the currently available COVID-19 vaccines are not live virus vaccines.
It is important to look at the different types of vaccines for a better understanding of how they work. The two main types of traditional vaccines are either live attenuated viral vaccines or inactivated viral or bacterial vaccines.
Live attenuated viral vaccines are made by modifying and weakening a live virus in a lab with the goal of stimulating immunity by injecting, swallowing or inhaling a small amount of the attenuated virus into the body to allow the immune system to recognize it and resist infection when encountering the wild type virus in the future. Live attenuated virus vaccines include the measles, mumps and rubella (MMR), varicella zoster, rotavirus and the influenza nasal spray.16
With live virus vaccines there is a risk that the recipient, especially those who are immune compromised, could get sick with a vaccine strain of the disease that the vaccine was designed to prevent.17 Live viral vaccines also come with the risk that recipients can shed and transmit vaccine strain virus to others. The vaccine strain virus can also combine with circulating wild-type virus and create a new variation of the virus with unknown and unpredictable risks.18
It is well established that, “vaccine strain live virus is also shed for varying amounts of time in the body fluids of vaccinated people and can be transmitted to others.19
One example of viral shedding post vaccination has been demonstrated with the influenza vaccine nasal spray, Flumist.
In one study, MedImmune reported that after FluMist vaccination 89 percent of babies between six and 23 months of age shed vaccine strain live influenza virus and 20 percent of adults between 18 and 49 years old shed vaccine virus. Vaccine-strain virus shedding reached a peak between two and three days after FluMist was inhaled and shedding was generally finished by day eleven.20
The risk of infecting others after receiving a live virus vaccine is well known. In a 1997 New York case, a physician was held legally accountable based on negligence and malpractice to the immediate family of an infant he had recently given live oral polio vaccine because, “administration of oral polio vaccine to an infant creates a well-recognized danger to parents of incurring contact polio.” When the father of the recently vaccinated infant contracted paralytic poliomyelitis and became permanently paralyzed, the doctor was found to be negligent for failing to comply with the vaccine manufacturer’s recommendation to warn plaintiffs of the risk of exposure to polio from their infant’s vaccination or advise them on taking necessary precautions.21
In contrast, inactivated viral and bacterial vaccines contain lab altered microbes that have been inactivated by heat or chemicals such as formaldehyde or are genetically engineered and, therefore, cannot replicate or shed. These vaccines are given in multiple doses with the goal of having the first dose “prime” the immune system and future doses providing protection.
There are different types of inactivated vaccines, such as polysaccharide and polysaccharide conjugate vaccines, which contain long chains of sugar molecules, or attach the polysaccharide to a protein antigen carrier to increase immungenicity. The haemophilus influenza B (Hib), meningococcal and pneumococcal vaccines are polysaccharide vaccines.22
Inactivated genetically engineered recombinant vaccines are produced by using a part of a microbe’s gene and inserting it into another cell’s genes so that when that cell reproduces, it produces vaccine proteins that the immune system recognizes and protection is conferred. The recombinant hepatitis B vaccine antigen is a hepatitis B virus protein produced by yeast cells into which the genetic code of the viral protein has been inserted and, in 1986, it was the first recombinant vaccine to be licensed in the U.S. HPV vaccine, which contains virus like particles (VLPs) and was licensed in the US in 2006, is also a recombinant vaccine.23
None of the currently available COVID-19 vaccines are live virus vaccines and, theoretically, should not carry a risk of vaccine strain shedding or cause symptoms of SARS-CoV-2 infection post vaccination.
What Type of Vaccines are the COVID-19 Vaccines?
Currently, there are two types of COVID-19 vaccines available in the U.S. under Emergency Use Authorization (EUA).
The Pfizer/BioNTech and Moderna vaccines are the first COVID-19 vaccines to be granted an EUA and the first vaccines using messenger RNA (mRNA) technology in humans. The experimental mRNA vaccines have not been officially licensed by the FDA but are being distributed under a special EUA to respond to the government’s pandemic public health emergency declaration.24
On Apr. 13, 2021, the FDA halted EUA distribution of the experimental Johnson & Johnson COVID-19 vaccine in the U.S. due to safety concerns related to blood clots. On Apr. 23, the Advisory Committee on Immunization Practices (ACIP) voted 10-4 with one abstention to lift the pause in distribution of J&J’s COVID-19 vaccine, with J&J reportedly agreeing to include warning language that, in rare instances, the vaccine can cause thrombosis (blood clots) in woman under age 50.25 The AstraZeneca experimental COVID-19 vaccine, which has been associated with blood clots in countries where that vaccine is distributed, has not yet been granted a EUA for distribution in the U.S.26 27
The mRNA COVID-19 vaccines do not include any part of the SARS-CoV-2 virus. Instead of delivering an attenuated or inactivated virus or part of a virus into the body, COVID-19 mRNA vaccines deliver genetic information that provokes the body’s own cells to produce a viral protein that will provide protection.28 It is hoped that this immune response will prevent the recipient from developing symptoms of COVID-19 disease if the SARS-Cov-2 virus is later encountered.29 30
Lipid nanoparticles containing synthetic mRNA allow the vaccine to get into the intracellular space past the cell wall prompting the cell to make viral proteins that in turn, stimulate the immune system.31 In short, an mRNA vaccine tricks the body into becoming a manufacturer of viral proteins that should trigger an immune response.32
According to the Moderna website:
mRNA medicines aren’t small molecules, like traditional pharmaceuticals. And they aren’t traditional biologics (recombinant proteins and monoclonal antibodies)—which were the genesis of the biotech industry. Instead, mRNA medicines are sets of instructions. And these instructions direct cells in the body to make proteins to prevent or fight disease.33
Viral Shedding During COVID-19 Infections
When a person sick with symptomatic COVID-19 disease sheds SARS-CoV-2 viral particles into the environment, they are contagious. Virus shedding is believed to occur with COVID-19 disease starting before a person is symptomatic until approximately eight days after the onset of symptoms, but viral shedding can last as long as 70 days in immunocompromised individuals.34
It is not known whether a person who received the COVID-19 vaccine can shed or transmit the virus if they become infected after being vaccinated. Clinical trials conducted by COVID-19 vaccine manufacturers did not test for the potential of vaccinated persons to become infected with SARS-CoV-2 and shed the virus with or without symptoms of disease.35James Sepulveda, executive director of the Institute for Global Health Sciences at the University of California explained, “We just do not know yet the answer to (that) question. The clinical trials were not designed to have that as an endpoint.”36
Dr. Dyan Hes, founder of Gramercy Pediatrics in New York city confirmed:
We don’t have the clinical trials to show that people who are vaccinated are not shedding the virus. They might not be getting sick, but they might still be shedding if they got it.37
The COVID-19 vaccine is not 100 percent effective at preventing infection with SARS-CoV-2. For example, the Pfizer vaccine, even with its purported 95 percent effectiveness, has not been proven to eliminate all traces of the virus in recipients according to Dr. Maria Elena Bottazzi, co-director of Texas Children’s Center for Vaccine Development and associate dean of the National School of Tropical Medicine at Baylor College of Medicine. A fully vaccinated person may not show symptoms of COVID-19, but that does not mean that they are not contagious and shedding SARS-CoV-2 as the asymptomatic spread of the virus has been well documented.38
According to Dr. Joel Ernst, an immunology and infectious disease expert at the University of California San Francisco, “in the absence of any other information, it’s safe to assume that “having antibodies won’t protect you from shedding the virus.”39
The bottom line is that COVID-19 vaccines may or may not prevent viral shedding and transmission of SARS-CoV-2 if a vaccinated person becomes infected with the virus. The increasing numbers of break-through cases of COVID-19 illnesses in vaccinated persons makes it essential for vaccine manufacturers and public health officials to investigate and calculate the risk of vaccinated persons shedding and transmitting the new coronavirus to others if the vaccine fails to protect them.
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Click here to view References:
1 U.S. Centers for Disease Control and Prevention (CDC). When You’ve Been Fully Vaccinated. Apr. 2, 2021.
3 Stieber Z. 5,800 Fully Vaccinated Americans Have Contracted COVID-19, 74 Dead: CDC. The Epoch Times Apr. 15, 2021.
4 Winsor M. Of 1.2 million fully vaccinated people in Washington state, 100 have gotten COVID-19. ABC News Mar. 31, 2021.
5 Musumeci N. Fauci: ‘Breakthrough’ COVID cases post-vaccination are ‘not surprising’. New York Post Mar. 26, 2021.
6 Crist C. Reports of ‘Breakthrough’ COVID Cases After Vaccine. WebMD Mar. 8, 2021.
7 Bandur M. State tracking ‘vaccine breakthrough’ cases, fully vaccinated people who test positive for COVID-19. KE TV Mar. 31, 2021.
8 Camarda N. 97 rare “breakthrough” COVID-19 cases have been recorded in Idaho. Idaho News Mar. 31, 2021.
9 Steinbuch Y. 246 ‘fully vaccinated’ Michigan residents get COVID-19, three die: report. New York Post Apr. 6, 2021.
10 Bolden L. Dozens in Central Florida contract COVID-19 after being fully vaccinated. clickOrlando Mar. 30, 2021.
11 Steinbuch Y. 246 ‘fully vaccinated’ Michigan residents get COVID-19, three die: report. New York Post Apr. 6, 2021.
12 Miller C. Since January, 142 Houstonians tested positive for COVID 14 days after being fully vaccinated, data shows ABC13 Apr. 12, 2021.
13 Browne E. COVID Vaccine Breakthrough Cases Explained As People Catch Virus After Shot. Newsweek Apr. 1, 2021.
14 Stieber Z. 5,800 Fully Vaccinated Americans Have Contracted COVID-19, 74 Dead: CDC. The Epoch Times Apr. 15, 2021.
15 Musumeci N. Fauci: ‘Breakthrough’ COVID cases post-vaccination are ‘not surprising’. New York Post Mar. 26, 2021.
16 How Vaccines Work. PublicHealth.org.
17 Moore A. Flu Vaccine Guidance For Patients With Immune Deficiency. American Academy of Allergy Asthma & Immunology Sept. 15, 2020.
18 Fisher BL. The Emerging Risks of Live Virus and Virus Vectored Vaccines: Vaccine Strain Virus Infection, Shedding and Transmission. National Vaccine Information Center November 2014.
21 Tenuto v. Lederle Labs, 90 N.Y.2d 606, 613 (N.Y. 1997).
22 Principles of Vaccination. CDC Pink Book.
24 Fisher BL. Over 3,000 “Health Impact Events” After COVID-19 mRNA Vaccinations. The Vaccine Reaction Dec. 22, 2020.
25 Soucheray S. ACIP opts to lift pause on Johnson & Johnson vaccine. CIDRAP Apr. 23, 2021.
26 Loelace B, Kopecki D. FDA advises states to pause use of J&J Covid vaccine after rare blood-clotting issue affects 6 women, kills 1. CNBC Apr. 13, 2021.
27 Cohen E. Government vaccine advisers say they don’t foresee AstraZeneca vaccine being used in the US. CNN Apr. 9, 2021.
28 Parpia R. Moderna to Use New mRNA Technology to Develop Coronavirus Vaccine. The Vaccine Reaction Feb. 12, 2020.
29 CDC. Understanding mRNA COVID-19 Vaccines. Mar. 4, 2021.
30 Donvito T. Can You Test Positive for COVID-19 After Getting the Vaccine? MSN Feb. 9, 2021.
31 Cross R. Will the coronavirus help mRNA and DNA vaccines prove their worth? Chemical and Engineering News Apr. 3, 2020.
32 Five things you need to know about mRNA vaccines. Horizon Magazine Apr. 1, 2020.
33 The Science and Fundamentals of mRNA Technology. Moderna.
34 What’s the difference between viral shedding and reinfection with COVID-19? The Conversation Nov. 30, 2020.
35 CDC. Key Things to Know About COVID-198Vaccines. Mar. 13, 2021.
36 McNamara A. Could people still be infectious after they’re vaccinated for COVID-19? CBS News Dec. 11, 2020.
39 Insuredwell. Could people still be infectious after they’re vaccinated for COVID-19? HealthinsuranceBlogpro.com. Dec. 11, 2020.