Pregnant and Concerned about COVID-19 Vaccines? A Primer to Put You at Ease

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Severe misinformation about health comes from a range of different sources, one being the anti-vaccination people. This is particularly relevant with respect to the public health response to the COVID-19 pandemic, featuring a handful of new vaccines. These vaccines have been accelerated through the regulatory process. That’s safe, as we shall see in our discussion, but, particularly when pregnant, a woman tends to worry about anything that goes into her body. With this perspective in mind, it is appropriate to consider a social media meme that has been circulating and that seems to have been written to spread unwarranted fear of the coming COVID-19 vaccines. By appropriate, I mean that it makes sense consider the meme’s claims, not because they hold any validity —they certainly do not, as you shall see— but to make you aware of this category of baseless arguments that have reached millions of people and that may be influencing people you know. The point is to utilize the misunderstanding to teach you about the new vaccines and why you should be happy, not worried, that they are almost ready one year after the pandemic broke.

As with my recent post about masks, the inspiration for today’s story, the anti-COVID-19 vaccine meme to which I refer above, popped up on the timeline of the individual from my hometown who apparently has descended into the world of conspiracy myths (please don’t use the term ‘conspiracy theory’; a theory is something that has reached a high level of certainty in science). Basically, what his recently posted anti-vaccine meme does is to pose, rhetorically, the question: “And yet, in 1 year, we have a vaccine for Cov-19 [sic] and you want me to take it?” The meme does this after saying that there is no vaccine for HIV nor for the common cold, that “the flu vaccine is a joke, and that, “At least 100 years of research and there’s no vaccine for cancer.”

Of all of this, the part most likely to get you worried, whether or not you are pregnant, is the part about the “a vaccine” for COVID-19 being developed and readied in only a year, as if vaccine researchers just started working from scratch back when we first started discussing this horrible disease in the early weeks of this year. So let’s begin by noting that the COVID-19 vaccines —not “a” vaccine, but several, including three that we have discussed thus far (Pfizer-BioNTech (already being distributed to healthcare workers and others in high risk categories), Moderna, and AstraZeneca-Oxford)– did not rise up from nothing beginning a year ago. Rather they are the result of many years of research and development, triggered by outbreaks of diseases caused by two other coronaviruses. One of these diseases, known as SARS, is caused by a virus called SARS-CoV1, identified in 2003. The other, known as MERS, is caused by a virus called MERS-CoV, identified in 2012. Both of these coronaviruses cause disease in humans and also cause a natural immune response because of a particular protein, or antigen, that is expressed on the surface of the viral particles. Known as the spike protein, this protein is what gives coronaviruses their name, as it causes crownlike appearance when the viruses are imaged with electron microscopy. Since it’s that same spike protein on the virus known as SARS-CoV2 (the virus that causes COVID-19), accounting both for the ability of the virus to infect cells and cause disease and for the immune response, researchers were already developing COVID-19 vaccines when the pandemic hit last year. Due to technological advances, they were able to sequence the RNA molecule that carries the genome of the virus very quickly, within days of its discovery, and thus begin tweaking research that had been going on for years. What has been accelerated during 2020 is the clinical testing and regulatory process. This also represents a kind of advance, but it was possible to do this safely because a lot of money was put into the trials. Another major factor that accelerated testing is the rapid, extensive spread of the virus through Earth’s populations. In contrast with pre-clinical testing in which laboratory animals are given the disease-causing agent on purpose, clinical trials make use of the fact that volunteers in the phase 2 and phase 3 trials (when vaccines are tested for efficacy against the disease) can get infected naturally in the community. This natural infection happens less with an infection that is rare and more with an expanding pandemic. The accelerated infection rate amount clinical trial volunteers, in turn, shortens the time needed for clinical trials to generate statistically significant findings.

But this doesn’t mean that money and effort is all that’s needed to create a clinically useful vaccine. As tragic and deadly as the COVID-19 pandemic is, we actually are fairly lucky that the SARS-CoV2 virus has a protein on its surface that provokes a natural immune response that correlates with disease effects and also that doesn’t mutate at such a high rate as to make dozens of different versions of the antigen (the protein that the vaccine causes to be made to provoke the immune system). We can’t say the same thing for the various types of influenza viruses, nor for HIV, nor for that matter many (but not all) of the viruses that cause common colds (some colds are actually caused by coronaviruses much less lethal than SARS-CoV1, MERS-CoV, or SARS-CoV2. In the case of influenza, there are many different viruses and the genome for the proteins on their viral coats evolve and diversify quickly. This is why flu shots are designed to counter a few different influenza viruses at once (the ones predicted to be most common and dangerous in the particular year), why you must get a new flu shot each year, and why the effectiveness varies, although researchers are working on what’s called a universal influenza vaccine, which, once developed, will negate the need for yearly updates. To learn more about the seasonal flu vaccine and why it is extremely important to be vaccinated, particularly this year, see this recent post of mine.

In the case of HIV, the virus mutates exquisitely quickly so you don’t get the kind of stable antigen like the spike protein that stimulates natural immunity that can be the basis of a vaccine; consequently, development of HIV vaccines has indeed been going on for decades with none yet available to you.

As for the part of the meme about there being no vaccine for cancer, there are several things wrong with this idea, the first being that there ARE vaccines that prevent certain cancers and actually do an excellent job to that effect. To unpack this better, we first need to clarify that the word “cancer” does not refer to one single disease, but literally to thousands of different diseases and there are two categories of cancer vaccines. There are vaccines against infectious agents, given to prevent disease, and most cancers are not known to have an infectious cause. But one of the cancers that does have an infectious cause is a type of cancer that you have read about several times here on The Pulse.

Of course, I’m talking about cervical cancer —squamous cell carcinoma of the cervix— caused by a family of viruses called human papilloma viruses (HPV). This type of cancer is life-threatening if it spreads beyond a limited region in the cervix, BUT its precancerous, easily-treatable stages are detected in Pap smear testing. Other factors, such as smoking, increase a woman’s risk, but HPV infection is the biggest factor, and so the disease is entirely preventable by way of immunization with an HPV vaccine. Cervical squamous cell carcinoma is one of the first cancers that has been conquered utterly and it happened because of a vaccine. Because varieties of HPV also cause other cancers, such as penile cancer in males, throat cancer in males and females, anal cancer in both males and females, and a certain type of skin cancer —squamous cell carcinoma of the skin— HPV vaccination also prevents these types of malignancies, all of which result from changes in what are called squamous epithelial cells, which are particularly susceptible to cancerous changes resulting from HPV infection. HPV vaccines are thus a wonderful example of a vaccine success against a particular cellular category of cancer.

A similar example is the vaccine against hepatitis B, which, like HPV vaccination, is also extremely effective. Hepatitis B is a major cause of hepatocellular carcinoma —liver cancer— although it’s not the only cause. Its contribution as a risk factor for this type of cancer varies among populations around the globe, but without question, the advent of hepatitis B vaccination has prevented a very large number of liver cancers from ever occurring, and so this is another example of a vaccine against cancer.

Finally, we should mention that the other category of cancer vaccines, namely therapeutic vaccines, which constitute a main component of what doctors call immunotherapy, which is becoming increasingly important in the growing anti-cancer arsenal.

Bottom line: vaccine research is very advanced and you should trust health authorities and ignore any crazy health memes that you may find circulating in your social media timelines.




David Warmflash
Dr. David Warmflash is a science communicator and physician with a research background in astrobiology and space medicine. He has completed research fellowships at NASA Johnson Space Center, the University of Pennsylvania, and Brandeis University. Since 2002, he has been collaborating with The Planetary Society on experiments helping us to understand the effects of deep space radiation on life forms, and since 2011 has worked nearly full time in medical writing and science journalism. His focus area includes the emergence of new biotechnologies and their impact on biomedicine, public health, and society.

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