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I received a combination of different WHO EUL vaccine doses for my vaccination, and I have not contracted COVID-19 before. Is the combination valid?



The acceptable combinations and minimum intervals between doses for persons who have not contracted COVID-19 before are as follows:

[Manufacturer] Name of Vaccine

Minimum Doses

Minimum Acceptable Interval Between Doses

Any two of the following WHO EUL vaccines (W):


  • [Pfizer/BioNTech] BNT162b2/ Comirnaty®)

  • [Moderna] mRNA-1273/Spikevax

    [Astrazeneca] Vaxzeveria AB/ AZD1222 (ChAdOx1-S)

  • [Serum Institute of India] CovishieldTM

  • (ChAdOx1_nCov-19-S), NVX-CoV2373/Covovax [Bharat Biotech] BBV152/ Covaxin®

  • [Novavax] NVX-CoV2373/ NuvaxovidTM

2 doses

 17 days

For combinations with these vaccines (S):

  • [Sinopharm] SARS-CoV-2 Vaccine

  • (VeroCell), Inactivated (lnCoV)

  • [Sinovac] COVID-19 Vaccine (Vero Cell),

  • Inactivated/CoronavacTM

Total 3 doses


(consisting of 1 or 2 doses of these vaccines)

17 days for both first interval and second interval


(*13 days for first interval if first vaccine is Sinovac-CoronaVac)

In addition to the combinations listed above, they should receive one further dose of a WHO EUL vaccine at least 150 days after the last dose to achieve minimum protection. For those who have received Sinovac/Sinopharm, they should receive one further dose of a WHO EUL vaccine at least 90 days after the last dose.

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