COVID-19 vaccines prevent severe illness not necessarily infection. Image by Alexandra_Koch from Pixabay

Get the Vaccine But Don’t Throw Out Your Mask Yet

Nancy R. Gough, PhD
Jan 18 · 5 min read

There appears to be quite a bit of confusion about what immunity means for the COVID-19 vaccines that are in use in the U.S. and Europe. These are the 2 mRNA-based vaccines and the DNA-based vaccine:

The first two diagrams show the mRNA-based vaccines by Moderna and BioNTech & Pfizer; the last diagram shows the DNA-based vaccine by Oxford University and AstraZeneca. [Made with; compiled by Nancy R. Gough, BioSerendipity,LLC]. Find out more

For these vaccines immunity means that the person who has been vaccinated with both doses will be protected against getting severe COVID-19, the kind that causes disease symptoms, hospitalization, the need for artificial ventilation, or possibly results in death.

The question: Can I get infected with the SARS-CoV2 coronavirus after getting the vaccine?

The answer: Likely, yes, but no studies have tested this yet.

Vaccinated people may still be able to get infected with the virus that causes COVID-19, but their immune system will react in such a way that severe disease or any symptoms are prevented from happening. The vaccine could convert infection into an asymptomatic case or a mild case or it could completely prevent infection. No one knows for sure yet.

Because a vaccinated person could still get infected with the virus, he or she could still infect a nonvaccinated person and that person could be someone that gets severe COVID-19 and winds up in the hospital or even dies.

This means that vaccinated people need to keep wearing their masks when in public. The vaccinated person still needs to protect other unvaccinated people from the possibility of contracting the virus.

The only potentially safe time to not wear a mask in the presence of others is if all of the people present have received both doses of a vaccine against SARS-CoV2, the virus that causes COVID-19. Even then, if one of the vaccinated people present is infected with the virus, this person could infect the other vaccinated people present. Critically, the exposure of vaccinated individuals to other vaccinated individuals who are infected with the virus could lead to the infection of not only the vaccinated person but others who have not been vaccinated and who come into close contact with the vaccinated and now infected person.

So, even if you have received both doses of the vaccine, keep wearing your mask to protect the unvaccinated from you. You could still transmit the virus to someone else. You could be just like the asymptomatic people who go on to infect someone who then develops severe COVID-19.

The vaccines protect against getting severe or symptomatic COVID-19, not necessarily against getting infected with SARS-CoV2.

Get vaccinated as soon as you are eligible but keep wearing a mask to protect others. Just because you got the vaccine and now you won’t get sick with COVID-19 doesn’t guarantee that you can’t get someone else sick with COVID-19 if you become exposed to the virus.

Question: Does the vaccine give you the virus?

Answer: No, the three vaccines described here cannot ever give someone the virus.

These vaccines give the vaccinated person the ability to make 1 viral protein. One viral protein does not mean you are infected with the virus. It means that your immune system can recognize this viral protein so that if you do come into contact with the virus, your immune system can attack it.

Vaccines that prevent infection or that reduce disease severity are both considered effective. The current vaccines have been shown definitively in clinical trials to prevent severe symptomatic COVID-19 disease incredibly well. We do not yet know if they prevent infection or spread.

Moderna Vaccine Trial Results:

Baden LR, El Sahly HM, Essink B, Kotloff K, Frey S, Novak R, Diemert D, Spector SA, Rouphael N, Creech CB, McGettigan J, Kehtan S, Segall N, Solis J, Brosz A, Fierro C, Schwartz H, Neuzil K, Corey L, Gilbert P, Janes H, Follmann D, Marovich M, Mascola J, Polakowski L, Ledgerwood J, Graham BS, Bennett H, Pajon R, Knightly C, Leav B, Deng W, Zhou H, Han S, Ivarsson M, Miller J, Zaks T; COVE Study Group. Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine. N Engl J Med. 2020 Dec 30:NEJMoa2035389. doi: 10.1056/NEJMoa2035389. Epub ahead of print. PMID: 33378609; PMCID: PMC7787219.

Pfizer Vaccine Trial Results:

Polack FP, Thomas SJ, Kitchin N, Absalon J, Gurtman A, Lockhart S, Perez JL, Pérez Marc G, Moreira ED, Zerbini C, Bailey R, Swanson KA, Roychoudhury S, Koury K, Li P, Kalina WV, Cooper D, Frenck RW Jr, Hammitt LL, Türeci Ö, Nell H, Schaefer A, Ünal S, Tresnan DB, Mather S, Dormitzer PR, Şahin U, Jansen KU, Gruber WC; C4591001 Clinical Trial Group. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. N Engl J Med. 2020 Dec 31;383(27):2603–2615. doi: 10.1056/NEJMoa2034577. Epub 2020 Dec 10. PMID: 33301246; PMCID: PMC7745181.

AstraZeneca and Oxford University Trial Results:

Voysey M, Clemens SAC, Madhi SA, Weckx LY, Folegatti PM, Aley PK, Angus B, Baillie VL, Barnabas SL, Bhorat QE, Bibi S, Briner C, Cicconi P, Collins AM, Colin-Jones R, Cutland CL, Darton TC, Dheda K, Duncan CJA, Emary KRW, Ewer KJ, Fairlie L, Faust SN, Feng S, Ferreira DM, Finn A, Goodman AL, Green CM, Green CA, Heath PT, Hill C, Hill H, Hirsch I, Hodgson SHC, Izu A, Jackson S, Jenkin D, Joe CCD, Kerridge S, Koen A, Kwatra G, Lazarus R, Lawrie AM, Lelliott A, Libri V, Lillie PJ, Mallory R, Mendes AVA, Milan EP, Minassian AM, McGregor A, Morrison H, Mujadidi YF, Nana A, O’Reilly PJ, Padayachee SD, Pittella A, Plested E, Pollock KM, Ramasamy MN, Rhead S, Schwarzbold AV, Singh N, Smith A, Song R, Snape MD, Sprinz E, Sutherland RK, Tarrant R, Thomson EC, Török ME, Toshner M, Turner DPJ, Vekemans J, Villafana TL, Watson MEE, Williams CJ, Douglas AD, Hill AVS, Lambe T, Gilbert SC, Pollard AJ; Oxford COVID Vaccine Trial Group. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK. Lancet. 2021 Jan 9;397(10269):99–111. doi: 10.1016/S0140–6736(20)32661–1. Epub 2020 Dec 8. Erratum in: Lancet. 2021 Jan 9;397(10269):98. PMID: 33306989; PMCID: PMC7723445.

Trial Reporting Controversy:

Vaccine Information:


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