El mirador

Covid19 vaccines. 25 frequently asked questions

English version of El Mirador on Vaccines and Vaccination Covid19


1. The covid19 vaccines, have already arrived?

Vaccines against covid19 are already being used and vaccination has begun, first in Russia and then in the United Kingdom.

The same vaccine used in the United Kingdom (Pfizer-BioNTech) has been approved in Canada and the United States, where it will also begin to be used in the coming weeks.

2. Are the two vaccines being used in Russia and the UK safe?
Yes. At least in the short term.

In the short term there are no major harms. No major adverse effects have been shown in basic studies to license vaccines (double-blind, randomized, controlled trial).

In practice, after the injection, there have been some cases of severe allergic reaction (anaphylaxis) in the UK with the Pfizer-BioNTech vaccine.

In basic studies, in some patients, especially with the second dose, there has been severe pain at the injection site, fever, malaise and chills that prevent normal life. And some suspicion of neurological damage, such as facial paralysis, and lymphadenopathy.

In the long term we don’t know anything.

Nor do we know anything in special groups or situations, such as those who have various allergies, ethnicity and/or genetic variations, etc.

Of particular concern is that there are problems with genetic intervention.

3. Are vaccines against covid19 free?

They are free in Russia and in the United Kingdom and will be free in Spain and everywhere.

Free vaccination plans are being established in all countries, prioritizing essential workers and the most vulnerable groups, such as workers and the elderly in nursing homes.

That they are free does not mean that the vaccines do not cost, but we do not know the prices paid by the public health systems since the contracts are considered “trade secret”.

We know that the cheapest vaccine will be that of AstraZeneca-Oxford as it has promised to sell it at cost (about 2.5 euros) for the duration of the pandemic. The rest can cost ten times as much.

4. Will it be mandatory to get vaccinated?

Vaccination will be voluntary.

It will be mandatory only in the strict situations provided for by the Public Health Law, like any other vaccine.

5. Will they ask us for our “vaccination card” for activities such as traveling, working and others?

It would be absurd, since it would lack science, ethics, justice and solidarity. The uncertainty is permanent regarding their practical results.

Furthermore, we do not know if vaccines will decrease the transmission of the virus.

We also do not know if they will produce “herd immunity” (group, population).

6. Do we have data on the effect according to vulnerable groups?
No, or very scarce.

Vaccines are generally studied first in healthy, young people.

In patients, in basic studies, little or no impact has been shown in people from vulnerable groups, for example with asthma, emphysema-COPD, diabetes, hypertension, heart problems, etc.

7. Can people be vaccinated with immunosuppressants treatments, such as chemotherapy for cancer or glucocorticoids and/or monoclonal antibodies for rheumatoid arthritis, ulcerative colitis, psoriasis, etc?

Immunosuppressed people, including people receiving immunosuppressive therapy, may have a lowered immune response to the vaccine.

No data are available on the concomitant use of immunosuppressants.

8. I am being treated with anticoagulant medications, can I get vaccinated?

Persons receiving anticoagulant therapy or those with a bleeding disorder that would contraindicate intramuscular injection should not receive the vaccine unless the potential benefit clearly outweighs the risk of administration.

9. “I am already very old, I did not get the covid19 when everyone got it in my nursing home. I seem to be resistant to the bug. Will I have to get vaccinated?”
Yes, in principle.

But we have few results from basic studies that concern the elderly.

In general, these studies preferably include healthy people between 18 and 65 years of age.

10. Can they be used during pregnancy and lactation?

They have not been studied in pregnant women or women during lactation. The recommendation is not to use it in these situations.

In women of childbearing potential, pregnancy should be excluded before vaccination. In addition, women of childbearing potential should be advised to avoid pregnancy for at least 2 months after the second dose.

Covid19 vaccines should not be used during breast-feeding.

11. Do vaccines harm fertility?
We do not know.

Reproductive toxicity studies in animals have not been completed.

12. Can vaccines be used in children and teens?
We do not know.

There are no data to establish its effect during childhood/adolescence.

13. How long does the immunity produced by the vaccine last?
We do not know.

For now it can be said that with two doses the immunity could be similar to that of having get the disease.

We do not know if the vaccination would have to be repeated to maintain immunity in the longer term.

14. Will vaccines prevent deaths from covid19?
We do not know.

Studies prior to the authorization of covid19 vaccines do not allow us to know if complications, hospitalizations, admissions to intensive care units or deaths will decrease.

For now it is reckless to say that “the covid19 vaccine will save lives” (that it will “prevent deaths”). Hopefully it’s true in the end!

15. So what do vaccines prevent?
Mild cases of covid19 (the “symptomatic cases”).

The Gamaleya vaccine have only published the final results in press releases, not in scientific journals.

The Gamaleya vaccine (Sputnik V) has an efficacy of 91% and that of Pfizer-BioNTech (BNT162b2) 95% (and data suggest that it may also reduce severe cases).

With data from the Pfizer-BioNTech vaccine, at two months of follow-up, out of every 10,000 vaccinated, 4 will have covid19. And out of every 10,000 not vaccinated, 88 will have covid19.

It is a reduction of 84 cases of mild covid19 per 10,000 vaccinated. That is, the vaccine will not offer any benefit to 9,916 people and will expose them to its adverse effects.

There is another vaccine, from Moderna, with an efficacy of 95%, which has been shown to prevent serious cases of covid19, but it is not yet commercialized nor has its results been published in a scientific journal.

ADDED 12/19/20: “The US FDA has approved the use of Moderna’s vaccine without having published any scientific text yet. The results presented to the FDA show an efficacy of 94.1% in preventing mild cases of covid19. That is, up to nine weeks after the last dose, 8 out of 10,000 vaccinated will have covid19 and out of 10,000 unvaccinated, 132. This is a reduction of 124 cases of mild covid19 per 10,000 vaccinated. In other words, the vaccine will not offer any benefit to 9,876 people and they will be exposed to the possible adverse effects of it “.

The vaccine, from AstraZeneca-Oxford, which has published its results in a scientific journal, has an efficacy between 62 and 90%, depending on the vaccination schedule.

16. If you have got the covid19, is it beneficial to get vaccinated?
We do not know.

We do not know how long natural immunity lasts, or if such immunity is beneficial or harmful compared to the immunity caused by the vaccine.

In any case, the possibility of re-infection by SARS-CoV-2 is extremely rare (in the world there are 27 documented cases).

In some vaccines, such as against dengue and Q fever, a determination of antibodies in the blood must first be made because if there are antibodies the vaccine becomes dangerous, even fatal, due to the immune reaction it causes.

17. If I get vaccinated against covid19, can I get vaccinated at the same time with other vaccines?

We do not know if there would be problems in this case.

18. Will we be able to choose between the different vaccines?
Presumably not (within the public health system).

We do not know what the criteria will be for vaccination with the different vaccines.

We know that, in addition to free public vaccination according to the official schedule, in Australia (and perhaps the world) vaccines will be sold in pharmacies and will be dispensed by prescription.

That is, whoever can pay for them will be vaccinated without having to comply with the public calendar dates and its groups.

19. Will we be able to “return to normality” with the vaccines?
Probably not.

Vaccines against covid do not seem to make the problem of the pandemic “disappear”.

We will have to follow the hygiene rules and others.

For example, Scotland’s chief minister has advised Scots not to take out plans for the 2021 summer holidays (unless they are reimbursable contracts if the pandemic persists).

20. What vaccines have already Russia and the UK?
Two different.

The Gamaleya vaccine (Sputnik V) is used in Russia and Pfizer-BioNTech’s (BNT162b2) in the UK.

21. How do these vaccines work?
With genetics from the virus itself.

These vaccines carry a genetic component of SARS-Cov-2 (the new coronavirus). In a certain sense, “the harm is fought with the harm itself” since what is injected is part of the genetic material of the virus that produces covid19.

They are vaccines that temporarily turn us into quasi-transgenic organisms so that we can make a virus protein.

The one from Russia carries the SARS-COV-2 genome in the form of DNA and is carried by another virus modified so that it does not infect (an adenovirus, a virus that produces colds, different in each of the two doses). That is, the Russian vaccine carries the SARS-COV-2 genome in the form of DNA and the DNA of the adenovirus. DNA is deoxyribonucleic acid, that of genes.

The Pfizer-BioNTech vaccine carries modified mRNA from the new coronavirus and is carried by lipid nanoparticles. The mRNA is ribonucleic acid, which allows the synthesis of proteins in ribosomes.

22. Will they really inject us with genetic material from the new coronavirus?

These vaccines carry part of the genetic material of SARS-CoV-2.

It is viral, non-human genetic material that transforms human cells into “factories” to produce a component of the “corona” of the new coronavirus. The virus already does this naturally: it releases its genetic material into our cells and “forces” the synthesis of its own proteins and its own genetic material.

Genetic vaccines “copy” this viral mechanism but only for a protein of the “crown” of SARS-CoV-2.

The vaccine, therefore, cannot produce covid19 (it does not inject the complete virus, only a small part of it).

The vaccine produces the SARS-CoV-2 antigen, which has no capacity to infect, it is just a protein that would allow the virus to adhere to human cells.

23. Do these genetic vaccines change human genetics?

They only impact is outside the nucleus of the cell.

They do not change the genetic material of human cells, they only make protein “factories” work.

The viral genetic material acts by itself, it does not produce changes in the human genetic material (at least in the short term).

24. How is that?
As a consequence of the injection of viral genetic material, human cells “are forced” to produce viral material and the body creates defenses against this material.

The viral component produced by human cells is an antigen, a “foreign” protein and therefore defenses against it are produced (antibodies are produced and can be measured in the blood and they are changes in immune cells).

Those defenses are the ones that will later protect us from having covid19.

25. Is there experience with other vaccines of this style, genetic, against other diseases?
Yes and no.

There is experience with vaccines similar to the vaccine (with DNA) being used in Russia, Spuntnik 5.

There is no experience with vaccines (with mRNA) similar to the one being used in the UK, Pfizer-BioNTech.

A genetic DNA vaccine against Ebola from Merk has been used successfully, with more than 300,000 vaccinated, in the Democratic Republic of the Congo in 2018, and in 2020 in another outbreak, in the same nation and in Burundi, Rwanda, South Sudan and Uganda.

The AIDS vaccine was a failure, a genetic vaccine with DNA, which was tested in South Africa and led to an increase in the spread of the immunodeficiency virus (HIV) in those vaccinated. Just the opposite of what you wanted to achieve.

No vaccine of the style of the vaccine that is being used in the UK (Pfizer-BioNTech) has ever been used. Its the first time.

In summary: Are you going to get vaccinated, doctor?

You have to take into account that each person is a different world, being professional, patient or just a person of the population of a country.

My example does not serve as a general norm, since everyone has their circumstances and their own fears and values, but in this case I believe that prudence advises a “wait and see” attitude.

It is what is technically called “intentional therapeutic inertia”, the value and art of doing “nothing”, a logical and prudent option in this case with so much uncertainty https://onlinelibrary.wiley.com/doi/full/10.1111/1742-6723.12922

That is, it is about maintaining an expectant attitude by doing what needs to be done and that we know works (hand washing, avoiding poorly ventilated closed places, etc.) and avoiding the decision on vaccines until there is more knowledge https://www.actasanitaria.com/el-arte-y-la-ciencia-de-no-hacer-nada-inercia-clinica-intencionada/

In any case, it is important to remember the urgent need to implement without any doubt the “social vaccines”.
Regarding covid19, we can improve the conditions and social determinants in a similar way to the supply of drinking water with respect to water-borne infections. And that is long-lasting and serves as a “vaccine” against covid19 and against many other diseases https://www.actasanitaria.com/covid19-vacunas-habra-muchas-pero-solo-una-durarera-la-social/


This text has been made possible thanks to the information on daily clinical practice shared by health professionals at the online Covid19 Seminar, which has 342 professionals from 11 countries. 55%, doctors and residents of family/general medicine, and 80% Spanish. It has been in activity since March 24, 2020 https://covid19siap.wordpress.com/   http://equipocesca.org/covid19-del-estado-de-alarma-al-estado-de-solidaridad-siap-extraordinario/

The initiative on the patients’ questions came from Luz Vázquez Canales, a Valencian family doctor.


1. Doctor of a Spanish prison

My patients hardly ask about the vaccine.

I think because:

A. Many of them are drug addicts and often do not show much interest in other things.
B. They assume that they are going to do it without choice for two reasons: 1) the coercion (explicit or implicit) that is applied to almost everything in prison, and 2) perhaps more importantly, that for them the vaccine can be the key to being able to receive visits from their relatives again.

My patients may not be very representative of the general population, but I couldn’t stop responding.

What worries me most is not that patients do not ask, but that among my coworkers and my healthcare friends there is little or no criticism and it has been assumed that the vaccine is our new messiah.

2. Male rural doctor

Today I found an answer that has been quite understandable:
“You want to sell me a car and you can’t tell me what engine it has, what color, how many wheels … and even though you don’t know, you insist that I buy it. Well that does not give much confidence”.

3. Female rural doctor (Laura)

My lifelong hairdresser told me two days ago:
“Laura, I have read that the vaccine that they are going to give us carries mRNA. I don’t know what and that this is different from all the vaccines that have come out now.

Can you explain to me exactly what that mechanism means?

I don’t understand.

What I know so far is that when they vaccinated you they put the virus directly on you, but I don’t know what this “mRNA” thing is. But also what I have heard is that we can catch diseases with this new vaccine”.

We had a conversation of over an hour about this while I was putting the dye on. I couldn’t help but send you this magnificent article written by Juan through Juan Simó’s blog: http://saludineroap.blogspot.com/2020/11/vacunas-contra-la-covid-que-contienen.html

Curiously, the other client next to me also asked if I could send it to her.

The hairdresser told me:
“To my mother, who is very ill and has many diseases, I do want to get it on because I prefer her to die of a side effect of the vaccine than of the covid itself. I do not lose anything by putting it on, I know that he has little life left.
But my daughter, my husband and I are going to wait for now. What if we develop a disease with the genetic material that they are going to put on us? My daughter is young and has a great future ahead of her. I’m afraid, what do you want me to tell you?”

The client on my side was very happy that the British began to put it on them first, because if something happened we were going to see it before in them than in us.

4. Male urban doctor

I describe the conversation as I remember it, which is certainly not what it was, but that is the general memory problem.

At the end of the consultation due to an apparent respiratory infection, the patient comments:

Patient (P): Well, it seems that the vaccine will come soon … let’s see if it solves all this.
Doctor (D): Yes, it seems that it will be soon. But there are still many doubts about it.
P: I understand that I will have to get it on, right?
D: It is true that your case is of a vulnerable person, but it seems that the intention is to start with health personnel and people who live in nursing homes and institutions.
P: Sure. They seem to be working well, right?
D: Yes, they seem safe, but it will be necessary to see in what terms of efficacy they speak: do the vaccines prevent asymptomatic disease and limit transmission?, do they prevent complications, the hospital or ICU or deaths, which is what is ultimately interesting.
P: Ok.
D: And in your case, we will not know if your body’s response to the vaccine would be the same as in a healthy person.
P: I understand.
D: When they study any new drug, such as a vaccine, it is done in highly selected populations, and patients with severe disease such as cancer or chronic kidney failure, or with immunosuppressants treatment are generally excluded … Then we will not know exactly what effect is to be expected in people in the same situation. We do not yet have data in this regard, I suppose we will know more details when the studies are completed and its use is extended to the entire population.
P: Well, I will do what you tell me.



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Juan Gérvas

Médico general jubilado, Equipo CESCA (Madrid, España). [email protected]; [email protected]; www.equipocesca.org; @JuanGrvas