'It’s the right choice': Ontario doctors reassure the public on mixing Pfizer, Moderna COVID-19 vaccine doses
Ontario's top doctor is urging people who received their first dose of the Pfizer COVID-19 vaccine to not hesitate to get their second dose with the Moderna vaccine.
"We would ask that you not reschedule any appointment to try and get a second dose of Pfizer at a later date, as we have a large supply of Moderna coming right now," Dr. David Williams, Ontario chief medical officer of health said at a press conference on Monday.
"We are saying that if you have an opportunity, that you may proceed to go ahead and use Moderna as your second dose, as compared to Pfizer, because we want you getting the full protection as soon as possible."
He stressed that both mRNA vaccines are safe and effective and use similar technology, making them safe to mix.
"One of the key strategies to slow transmission and to keep the Delta variant under control and avoid a fourth wave is to get vaccinated as soon as possible," Dr. Williams said.
"First dose does protect you from severe consequences and hospitalization, but that doesn’t interrupt transmission. Second dose does interrupt the transmission."
If you had Moderna or Pfizer for your 1st dose, you can safely take either for your 2nd dose for strong protection. Both are recommended: https://t.co/CDNR286Eig. Thanks to all who've gotten vaccinated, you're making a difference & bringing us 1 step closer to the things we love. pic.twitter.com/QDNeRVymba
— Toronto Public Health (@TOPublicHealth) June 21, 2021
The City of Toronto announced over the weekend that due to delays in Pfizer shipments, city-run immunization clinics with only administer a Moderna mRNA doses to individuals 18 and older starting June 20. Pfizer supply will be reserved for children between the ages of 12 and 17, as Moderna has not yet been approved for that age group.
“While Team Toronto vaccination partners are facing a shipment delay, we must not delay the quick administration of doses," a statement from Dr. Eileen de Villa, Toronto's medical officer of health, reads.
"With the Delta variant growing at an exponential rate in Toronto, vaccines are one of our key strategies to slow transmission. Both Pfizer and Moderna mRNA vaccines are interchangeable, equally effective and safe for everyone over 18 years. If you have an appointment, keep it. If you don’t have an appointment for a first or second dose, make one as soon as you are eligible."
Due to an unexpected shipment delay, Peel vaccine clinics will be using Moderna for all appointments, except for those aged 12-17, starting Monday. pic.twitter.com/V01PZGTmlZ
— Region of Peel (@regionofpeel) June 19, 2021
Peel Region will also be reserving Pfizer doses for children, set to last until at least Thursday, June 24.
Medical experts in Ontario continue to reassure the public that it is safe to mix mRNA vaccines and the public should take the first appointment available to them.
No reason to think that Pfizer for dose 1 + Moderna for dose 2 would be any worse than 2 doses of Pfizer. So if you got Pfizer for dose 1 and are being offered Moderna for dose 2, rest assured that you are doing the right thing by getting it (and not waiting for Pfizer). 4/4
— Jeff Kwong (@DrJeffKwong) June 20, 2021
Just a reminder - if you got a flu shot this year, you likely don't know the brand. Neither do I. They're made by separate companies. We get a different flu vaccine yearly with the same mechanism. The two most common are below.
Moderna and Pfizer are interchangeable pic.twitter.com/8f7DG9dkLt— Zain Chagla (@zchagla) June 20, 2021
Just worked a vaccine clinic @OslerHealth. Most ppl are ok with mixing Moderna and Pfizer. The ones who aren’t ; just need reassurance. It’s the right choice. Both mRNA 💉are interchangeable! @thisisourshotca
— Taj Kaura (@drtajee) June 21, 2021
Apparently this needs to be said:
|-------———--|
| PFIZER |
| AND |
| MODERNA. |
| ARE |
| INTER- |
| CHANGEABLE|
|--------———-|
(\__/) ||
(•ㅅ•) ||
/ づ— David Fisman (@DFisman) June 14, 2021
5- I have no apprehension with Pfizer & Moderna being used interchangeably.
In an ideal situation, if both readily avail, then pick the one you received as 1st dose.
But nothing is ideal in a pandemic - having full protection with two doses is exceptionally critical.— Sabina Vohra-Miller (@SabiVM) June 21, 2021
Moderna is an mRNA vaccine that ialmost identical to Pfizer. One option for a second dose includes mixing these two (eg Pfizer then Moderna). The most important thing is to get that second shot to optimize immune protection. Moderna will get you there too!
— Sumon Chakrabarti (@TorontoIDDoc) June 21, 2021
A lot of concern about mixing the two mRNA vaccines. Due to the vagaries of global supply, most people who got Pfizer will be offered Moderna in the coming weeks. I'll show you why this is a great thing, and why its important to get your second shot as quickly as possible pic.twitter.com/35pRxOfSna
— Kashif Pirzada, MD (@KashPrime) June 21, 2021
the communication around vaccines has been wanting. but cannot stress this enough — if you are offered Pfizer or Moderna, please take first available.
— Andrew Baback Boozary MD (@drandrewb) June 21, 2021
#CovidVaccine mixing 🧵
➡️ science translated to real world settings in medicine
➡️ decisions are made based on several factors e.g #DeltaVariant
➡️ 💉 mixing is not new. You most likely got diff brand flu, hepatitis, measles 💉
➡️ mRNA 💉 same mech
More 🧵⤵️ #COVID19 https://t.co/Ry0mqiPwH1— Dr. Krishana Sankar (she/her) (@KrishanaSankar) June 21, 2021