Over the past two years, an unprecedented tsunami of pandemic information has guided and informed the decision making of governments, health-care workers, the global scientific community, and the public.
No other event in history has precipitated this level of intense and simultaneous research and exchange of expertise from scientists around the world in such a short period. New and evolving information make it difficult to keep up. Meanwhile, misinformation and fake news have muddied the flood of knowledge.
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CTVNews.ca has compiled a summary of essential COVID-19 facts and myths about the disease, masks, and vaccines, along with links to more in-depth stories we’ve written over the past year on these issues.
Read on to learn the latest scientific thinking on airborne spread, mask effectiveness, natural immunity and other important topics.
COVID-19 IS AIRBORNE
In the early months of the pandemic, when scientists were still learning about SARS-CoV-2, the virus that causes COVID-19, it was believed that transmission was primarily through contact with large droplets. Numerous studies have since shown that the virus is in the air. Transmission risks are highest in crowded, poorly ventilated, indoor spaces. One study, for example, showed how a choir singer likely infected members of his church choral group. Another study found that new variants were becoming more efficient at generating aerosols.
The World Health Organization (WHO) says current evidence suggests “the virus can spread from an infected person’s mouth or nose in small liquid particles when they cough, sneeze, speak, sing or breath. Another person can then contract the virus when infectious particles that pass through the air are inhaled at a short range (this is often called short-range aerosol or short-range airborne transmission).”
MASKS WORK
The global health community widely agrees that wearing a mask is a key, life-saving measure in helping to curb the spread of the virus. An overwhelming body of research – much of it available on the U.S. Centers for Disease Control and Prevention website – demonstrates masks’ effectiveness in substantially reducing viral transmission.
If you are infected, wearing a mask helps protect others by controlling the spread at the source – you. Whether you are healthy or immunocompromised, you are also protecting yourself by wearing a mask. It is a simple and non-intrusive method of lowering transmission, experts say. False claims that masks cause health problems or pose a greater threat than the pandemic itself have not been supported by research, the CDC says.
As the virus evolved, so have recommendations on the type of mask the public should use. Public health and medical experts recommend a well-fitted mask with good filtration, and medical grade masks for those who are high-risk. A three-layer cloth mask worked quite well for earlier variants, but Omicron’s high transmissibility prompted recommendations for N95s or KN95s and KF94s, which have extremely high filtration efficacy and can be reused a number of times.
Numerous studies have also shown that concerns that masks are harmful to children are unfounded. The American Academy of Pediatrics says masks will not affect a child’s ability to focus or learn, and will not affect a child’s lung development or weaken their immune system. It also does not trap carbon dioxide molecules, which are too small to be captured by breathable materials. Public Health Ontario also published a report that looked at data and studies on the issue, with similar conclusions. Meanwhile, U.S. counties that had mask mandates for school, for example, saw fewer pediatric COVID-19 cases compared with counties that did not have mask requirements. At least one study also found that young children can still tell how a person is feeling, even with a mask on.
Debunking face mask myths
Can you hack your face mask for a better fit? Researchers find out
What’s the difference between KN95 and KF94 masks?
How many times can you reuse an N95 mask? Experts weigh in
A health-care volunteer primes a syringe with the Moderna COVID-19 vaccine at Pinnacle Bank Arena on Friday, Jan. 22, 2021 in Lincoln, Neb. (Kenneth Ferriera/Lincoln Journal Star via AP)
VACCINE FACTS AND MYTHS
There are six different vaccines authorized in Canada now, based on four different technologies: Pfizer-BioNTech’s Comirnaty and Moderna Spikevax, which are both mRNA vaccines, and AstraZeneca’s Vaxzevria and Johnson & Johnson’s Janssen vaccine, which are viral vector-based vaccines. Novavax’s Nuvaxovid is protein-based and Medicago’s Covifenz is plant-based.
A mRNA vaccine teaches our cells to make a specific protein that triggers an immune response to produce protective antibodies. The protein itself is harmless,and the cells in our bodies quickly break down the mRNA after the instructions have been delivered and the protein made. It is not gene therapy and does not alter your genes because the vaccine does not enter into the part of the cell that carries our DNA genome.
A viral vector-based vaccine uses a harmless virus – like the ones that cause the common cold – as a delivery system. It too is designed to stimulate the immune system to create antibodies. The virus used has been altered so that it can not replicate or make you sick. It is also not the SARS-CoV-2 virus that causes COVID-19.
A protein-based vaccine is made from purified proteins and other additives administered to the recipient and designed to trigger an immune response. This particular method has been around for decades and is how vaccines for shingles and hepatitis work.
Medicago’s plant-based vaccine contains virus-like particles derived from plants, which serve as mini bioreactors. The plants read the genetic instructions of a particular virus and produce large quantities of virus-like particles, which are then harvested and made into a vaccine. The particles themselves do not contain genetic material so they are not infectious, but they imitate the structure of the virus which stimulates an immune response.
COVID-19 vaccines are not linked to a wave of deaths and illnesses among athletes and other healthy people, for example, despite deceptive video compilations circulating online suggesting otherwise. Sudden heart attacks among athletes have been the leading cause of death in athletes long before COVID-19 and are not suddenly increasing.
Vaccination outweighs risk of myocarditis and other heart issues, cardiologist says
Novavax and Medicago: How are their COVID-19 vaccines different from all the others?
What is the difference between mRNA and viral vector-based vaccines?
VACCINE SIDE-EFFECTS
As of February 25, 2022, there have been a total of 40,011 “adverse events” reported following vaccination, representing 0.05 per cent of all doses administered, according to publicly available data published by the federal government. Of the total, 31,596, or 0.039 per cent, are non-serious. Another 8,415 reports, or 0.01 per cent, are categorized as serious. Adverse events may be any unfavourable or unintended sign, such as a skin rash, or any abnormal laboratory finding, a symptom, or disease. An event is considered serious if it results in death, is life-threatening, requires hospitalization or extending existing hospitalization, results in persistent or significant disability, incapacity, birth defect, or congenital anomaly.
There is a rare possibility of developing mild myocarditis – an inflammation of the heart muscle – after receiving an mRNA shot. Numerous studies, the CDC and Health Canada, however, say the risk is low, resolves quickly, and importantly, the benefits outweigh the risks of catching COVID-19. Research from a large study found that the risk of new heart problems was significantly higher after recovering from a COVID-19 infection. Another large study, which looked at medical records covering one-fifth of the U.S. population found that the risk of myocarditis among teenage boys within three months of infection was about 450 cases per million compared with 67 cases per million after the second dose of an mRNA vaccine.
There have also been reports of thrombosis with thrombocytopenia syndrome (TTS) and Guillain-Barre Syndrome (GBS) following the AstraZeneca Vaxzevria/COVISHIELD vaccination and Johnson & Johnson’s Janssen shot. The CDC also consider these potential adverse events rare, noting that in the case of GBS, studies suggest that a person is more likely to get GBS after being infected with the flu than after vaccination.
There have been several dozen reported cases of blood clots caused by TTS involving the Janssen vaccine in the U.S., for example, out of more than 18.4 million doses administered. Only six cases of capillary leak syndrome involving AstraZeneca’s vaccine were reported out of 78 million doses administered in Europe and the U.K., according to Health Canada.
In the U.S., misinformation about vaccine safety spread in part due to information drawn from reports made on VAERS (Vaccine Adverse Event Reporting System), which can include information that is unverified, inaccurate, coincidental, or incomplete, the CDC disclaimer states.
What is an ‘adverse event?’ Inside the report on Pfizer’s COVID-19 vaccine
People are shown at the Bill Durnan Arena COVID-19 vaccination site in Montreal, Saturday, May 22, 2021. (THE CANADIAN PRESS / Graham Hughes)
VACCINES DO NOT GUARANTEE IMMUNITY
Real-world data and numerous studies show that vaccines significantly reduce the risk of hospitalization and death, proving that the vaccines work. You can still get a breakthrough infection, however, and you can also become asymptomatically infected. This in turn means you can still expose and transmit the virus to others, which is why protective measures are still useful even after vaccination, especially around those who are immunocompromised or otherwise vulnerable. The vaccines themselves can not give you the virus because they do not contain the actual live virus.
Yes, you can still get infected with COVID-19 after being vaccinated. Here’s why
Is it possible to get reinfected with Omicron?
VACCINES, FERTILITY, AND PREGNANCIES FACTS AND MYTHS
Millions of people have been vaccinated around the world,and there is no evidence to support the claim that the vaccines cause fertility issues, according to numerous medical health organizations, advisory groups, and studies. Stories claiming a spike in stillbirths among the vaccinated, for example, are false. Data looking at 35,000 pregnancies also found no mRNA vaccine safety concerns during pregnancy either, says Health Canada. Vaccine antibodies found in breast milk do suggest protective potential for babies, according to at least one study.
There is ample evidence, however, of the serious risks COVID-19 poses for those who are pregnant and unvaccinated, including a CDC report reviewing 1.25 million deliveries. Real-world hospitalization data and cases have also prompted groups like the Society of Obstetrician and Gynecologists of Canada to strongly recommend COVID-19 vaccines for individuals who are pregnant. A number of studies have found that a COVID-19 infection can cause pregnancy complications, and that severe COVID-19 and newborn deaths were more likely among those who are pregnant and unvaccinated.
No evidence linking vaccinations for children and fertility issues later in life: experts
Severe COVID-19, newborn deaths more likely among unvaccinated: study
Infection during pregnancy can cause inflammation, pregnancy complications: study
Post-mRNA vaccine antibodies in breast milk raises protective potential for babies
MAKING SENSE OF THE NUMBERS
When looking at COVID-19 data, context matters. Raw numbers are useful for hospitalizations because it helps capture how stretched the health-care system may be. But if we are trying to gauge the effectiveness of the vaccines in preventing hospitalizations and deaths, the numbers must be calculated as a proportion of the overall population in question: How many vaccinated patients were hospitalized or died out of the total number of people vaccinated? How many unvaccinated patients were hospitalized or died out of the total unvaccinated population?
Unvaccinated patients dying from COVID-19 at higher rates in several provinces
Making sense of the numbers: Greater proportion of unvaccinated are being hospitalized
The ‘grey zone’ hindering efforts to count Canada’s COVID-19 deaths
People wear masks as they wait for the arrivals at the International terminal at Toronto Pearson International Airport in Toronto on Saturday, January 25, 2020. THE CANADIAN PRESS/Nathan Denette
FORGET HERD IMMUNITY
While Canada has an impressive vaccination rate overall, reaching “herd immunity” with the coronavirus is unlikely, experts say. This is due in part to the enormous disparities in vaccination rates around the world – vaccine hesitancy in wealthier countries and poor vaccine access in low-income countries. Most children, especially those under five years of age also remain ineligible for a vaccine. At the same time, antibody protection wanes over time. These factors combined mean the virus will continue to survive and spread as long as it has the opportunity to keep mutating into new variants. Some scientists believe we may move to herd resistance instead, which means populations will be protected enough so that future waves in cases will become less disruptive to society.
Experts warn U.S. may never reach herd immunity with COVID-19. Here’s why
Canada may find it challenging to reach herd immunity from COVID-19, experts say
COVID-19 herd immunity unlikely, but ‘herd resistance’ a possibility, experts say
VACCINES VS NATURAL IMMUNITY
Numerous studies have looked at immune responses following vaccination and infection. In general, they show that both protect people from similar variants for at least six months, according to the CDC. The level of immunity after infection varies from person to person, however, due to differences in individual immune systems, the severity of the infection, for example. A growing number of studies and epidemiological evidence does show that getting vaccinated after an infection provides significantly better protection, including against more infectious variants.
The reason why the scientific and medical community do not advocate purposely catching COVID-19 to acquire natural immunity instead of vaccination, however, is due to the significant risks associated with COVID-19, even among the healthy. One study suggested that the overwhelming majority of patients hospitalized due to COVID-19 experience neurological complications, while another one looking at data from the U.S. Department of Veterans Affairs found that those who recovered from infection were at much greater risk of developing new heart problems. Another large U.K. study linked COVID-19 to significant “cognitive deficits”. Finally, countless people are now grappling with "long COVID," a condition following infection that results in a wide variety of symptoms including severe fatigue, mental health issues, brain fog, and other lasting effects.
Does a COVID-19 breakthrough infection actually give you ‘super immunity’?
Risk of new heart problems jumps after COVID-19: study
More than 80 per cent of people hospitalized with COVID-19 experience neurological complications: study
LONG COVID
It is not clear exactly how many people suffer from long COVID, or post COVID-19 condition, often characterized as extremely debilitating. One review of nine studies from around the world suggests that at least one in three people who were hospitalized with COVID-19 experience significant long-term health problems, such as multiple organ issues and poor mental health. A Danish study also suggested about a third of people experience persistent symptoms half a year to a year following infection. A study out of Norway found that symptoms could linger for up to half a year, even in mild cases among young people. Many Canadian “long-haulers” say they are dealing with cognitive impairment months later.
1 in 3 COVID-19 survivors suffer long-term health issues: review
Almost a third of people report lingering symptom 6-12 months after COVID-19: study
COVID-19 long-haulers report long-lasting cognitive impairment
Young adults with mild COVID-19 suffering from persistent symptoms six months after infection: study
Long COVID and children: expert panel agrees on definition, study says
BUSTING MISINFORMATION
The dissemination of fake news reached new heights during the pandemic, with one report out of the U.K. finding that misinformation coming out of Facebook communities grew by nearly 50 per cent during a six month period in the first year of the pandemic. Misinformation is often woven with partial truths, or facts taken out of context, which makes them appear more credible. For example, those who object to public health measures pointed to the survival rate of over 99 per cent, which is true. But in a population of tens of millions, that still translates to hundreds of thousands of people dying. Meanwhile, the vaccine shots, which underwent rigorous, carefully monitored, large-scale clinical trials prior to even being reviewed by Health Canada, are not in violation of the Nuremberg Code, which is about medical experimentation without consent.
‘It’s garbage’: Infectious disease expert debunks ‘Facts Not Fear’ flyer
Do vaccine mandates violate Canadians’ charter rights?
RELATED IMAGESview larger image
xjmtzywA nurse prepares a COVID-19 vaccine shot before the opening of a mass vaccination clinic in Mississauga, Ont., Friday, Dec. 24, 2021. THE CANADIAN PRESS/Chris Young
