Pfizer vaccine and blood transfusions

I wondered if those injected with the covid-19 Pfizer vaccine would pose any risks to those who opt not to be vaccinated when it come to donated blood and transfusions… Here is the New Zealand Blood Service‘s responses to my questions.

1.      Are there any risks to the health of a person who has been vaccinated with one type of Covid vaccine and then later receives blood from someone who has had a different type Covid vaccine?

The safety of New Zealand’s blood and blood product supply is always a priority and we defer donors when there is evidence that a drug or condition may negatively affect the quality of the blood transfused.

As there will not be any vaccine in the blood stream from our donors, we do not believe that there is any danger to a recipient receiving blood from someone who has had a different vaccine. With the Pfizer vaccine, we have a 12 hour stand down.

The active component of the Pfizer vaccine (MRNA) is quickly broken down and does not persist in the body outside the muscle cells for more than a few hours.

The spike protein, that the vaccine induces, is attached to the muscle cell and does not appear in the blood stream. Any donor who received a vaccine that has not been approved for use in New Zealand has a 28 days stand down.

This will ensure that there is no vaccine in the donor’s blood. Should other vaccines be approved for use in New Zealand, we will review the specific vaccine and determine an appropriate stand down period based on its mechanism of action.

2.      Should someone need blood who has chosen not to be vaccinated, and then later receives blood from someone who has, will the recipient be as good as vaccinated?

A recipient of blood from a vaccinated donor will not have been vaccinated. The Pfizer vaccine is not transmitted by blood.

The donor blood may contain some antibodies to Covid19 but these will be broken down over weeks to a few months, like all antibodies are. The recipient will not have any immunity of their own.

3.      Will NZ Blood service document on its blood products whether the blood is that of a vaccinated donor?

No, we will not be documenting on the blood whether a donor has been vaccinated. Donors have many different types of antibodies in their blood and antibodies to Covid19 are just one more.

The Pfizer vaccine is not transmitted by blood transfusion. All other vaccines not approved by Medsafe have a lengthy stand down period for the donor, so will not appear in the blood either.

4.      What tests are NZ Blood doing to see what effect, if any, Covid vaccinations are having on blood and blood products?”

New Zealand Blood Service (NZBS) are not testing to determine if Covid19 vaccinations are having any effect on blood. Blood services internationally, including NZBS, have a good understanding of vaccination in relation to blood donation.

NZBS shares information and discussion with other blood services around new medicines and vaccines, including Covid19, to determine if any services have identified potential impact on the quality and safety of blood products. 

Both NZBS and other blood services have not identified any blood safety concerns about the Pfizer vaccine that is in use in New Zealand.