COVID-19 vaccine FAQ

COVID-19 has affected everyone, one way or another these past 3 years. We hope that you have been able to stay healthy and safe. Our thoughts are with those who have lost loved ones. There have been many COVID-19 concerns among the aHUS community so, back in March 2020 an aHUS & COVID-19 webinar was held. In case you missed it or would like to see it again here is the link to the webinar:

 During 2020 there was much discussion about the development of an effective vaccine. Many vaccines are in development; since December 2020, Health Canada has approved several vaccines. For more info, click HERE for the Health Canada website.

 With the approval of several vaccines, we have had questions arising from our aHUS community such as: whether the vaccine is safe, can the vaccine cause a relapse, etc.

We would like to provide you with some general information that we have received. It is important to remember that this information should NOT be taken as medical advice and each person should consult with their own treating physician about what is right for them.

Is the Covid vaccine safe?

The approved vaccines have gone through a rigorous review by Health Canada and decisions are based only on scientific and medical evidence showing that vaccines are safe, effective and of good quality. The benefits must also outweigh the risks.

At this time, most physicians are in support of their aHUS patients receiving the vaccine and consider it safe, since the benefits outweigh the risks.

Since there is no long-term data yet, ongoing studies will continue.

What are the side effects of the vaccine?

In general, the side effects are within the range of regular vaccines. These are some common symptoms that people have described after receiving the vaccine:

-Sore arm and swelling around the area of injection.


-Body aches; general aching over the body which can last for a few days and feels like mild flu.

-Increased tiredness.

-Raised body temperature or a slight fever.

Can a COVID vaccine cause a relapse of aHUS?

Immunization in general could be a potential trigger for aHUS. However, patients on treatment should be generally protected. Thus, if you are on eculizumab and getting the vaccine, the potential risk for a relapse is very small. If you are not on eculizumab, a COVID vaccine could in theory lead to activation of aHUS and relapse in someone whose disease is inactive.

On the other hand, in theory, that individual could have a similar or worse aHUS relapse by a COVID-19 infection, leading to a more severe COVID illness, even though this has only rarely been reported. It is very important that close monitoring be done after vaccination to check for a flare of active disease.

Is the vaccine safe in kidney patients?

For people with kidney disease, COVID-19 can be very serious. Vaccination against COVID-19 for people with chronic kidney disease, including people receiving dialysis treatment or with kidney transplants is likely to be highly beneficial.

International kidney experts have reviewed the evidence and agree that the vaccines are safe for people with kidney disease, on dialysis and with kidney transplants.

Any small risk associated with the vaccination is likely to be significantly outweighed by the potential benefits against COVID-19.

Advice to individuals may vary because people with kidney disease often have other conditions too, so what is right for one person, may not be right for someone else. Your kidney doctors will advise you on what is best for you, so speak to them for more advice.

Additional general information on COVID-19 and the vaccines can be found at these websites:

Government of Canada website COVID-19 Vaccines

We hope this information has been helpful in providing some answers to questions you might have. 

Feel free to contact or if you have additional questions or concerns. We will do our best to continue gathering information and sharing it with our community.

Stay safe and healthy!