Coronavirus vaccination is a topical issue and we have many questions.
Konstantinos Papanikolaou, Pathologist - Infectious Diseases Specialist and Scientific Associate of "Health", answers the most important of them:
There is a case of getting sick with COVID-19 after vaccination;
No. The -so far- approved by the European Medicines Agency (EMA) vaccines, that is, those of Pfizer and Moderna do not contain the virus itself. Therefore they do not cause coronavirus disease, however, they may cause a low-grade fever during immune induction. This is part of the mechanism of action of the vaccine and is not a real disease. If someone gets sick during or shortly after the vaccination, this will happen because the patient was exposed to SARS-CoV-2 before the vaccine had time to build protection.
I will have a positive test for the virus after the vaccine;
You may have a positive antibody test in your blood a few weeks after the vaccine, as this is how protection against the virus comes about, by antibody production or after disease (natural immunity) either after vaccination. There is no way you can have a positive molecular test or rapid antigen test done in the nasopharynx or oropharynx to diagnose a current COVID-19 infection..
If I have passed COVID-19, I have to get the vaccine;
Yes. There is evidence that natural immunity after infection does not last long and does not completely protect against re-infection. It seems that natural immunity after infection lasts 3 with 12 months, but it is not the same for everyone and depends, among other things, on how severe the disease was (the more severe the disease, the longer the protective antibodies remain in the blood). Vaccination is therefore needed in this case as well, but probably a little later.
The vaccine protects me;
Yes, the vaccine provides protection by training the immune system to respond to the virus. The available data from the approved vaccines but also from those that have not yet been approved, indicate a high level of protection around 80 – 90%. This can avoid serious illness and complications of COVID-19. On the other hand, the continuous observance of protection measures is absolutely necessary (use a mask, hand hygiene, distance maintenance), even after individual vaccination, until herd immunity is established in the general population through mass vaccination.
MRNA vaccines affect my DNA;
No. The messenger RNA of the virus does not enter the nucleus of the cell where our DNA is located. It simply gives our cell a temporary command to produce virus protein, against which our immune system then reacts and is eventually trained to react to the virus.
What are the most common side effects of the vaccine?;
• Systematic: low fever, chills, hardship, myalgias, motion sickness, diarrhea, vomiting.
• Local: pain at the injection site, erythema.
If I have allergies the vaccine is dangerous;
Hypersensitivity reactions have been reported in approximately 2% of vaccinated. Most are mild, However, there were a few cases of rash that required treatment with epinephrine (adrenaline).
• If you have allergies to food or oral medications you can get the vaccine normally.
• If you are allergic to another vaccine or injectable medicine it is advisable to consult your doctor.
• If you have a history of allergies to PEG (polyethylene glycol) contained in mRNA vaccines, or another component of the vaccine, it is recommended that you do not get vaccinated with these vaccines.
• If, end, you reacted immediately (in less than 4 hours) after the first dose of vaccine mRNA, it is recommended not to take the second dose.
Konstantinos PapanikolaouKonstantinos Papanikolaou
Pathologist - Infectious Diseases Specialist
Scientific Associate HYGEIA