COVID-19 Vaccines and Bleeding Disorders: Frequently Asked Questions (FAQs)

NHF recognizes that individuals with bleeding disorders may have questions and concerns relevant to the new COVID-19 vaccines, including any implications specific to their conditions. The following FAQs are therefore meant to address some of the most common questions. Please note that these answers were created for broad purposes and that affected individuals should engage closely with their healthcare provider to discuss the possibilities of vaccination, including potential contraindications (if any), and specific questions related to safety and efficacy. Given the nature of this virus, rapid developments in vaccines, and the upcoming transition in our federal government, this continues to be a very fluid situation.

Two mRNA COVID-19 vaccines – from Pfizer-BioNTech and Moderna – have already been approved and are currently being administered to people in the US and internationally. There are several other vaccines that are in development and will be considered for “Emergency Use Authorization” (EUA) from the U.S. Food and Drug Administration (FDA), including two viral vector vaccines – developed by Oxford-Astrazeneca and Johnson & Johnson.  These additional vaccines are currently in large, phase III clinical trials and yielding promising results thus far. NHF will keep the bleeding disorders community updated as new information becomes available.

What is an “Emergency Use Authorization” (EUA)?

An Emergency Use Authorization (EUA) is a mechanism to facilitate the availability and use of medical countermeasures, including vaccines, during public health emergencies, such as the current COVID-19 pandemic. Under an EUA, FDA may allow the use of unapproved medical products in an emergency to diagnose, treat, or prevent serious or life-threatening diseases or conditions such as infection with the virus that causes COVID-19 disease when certain statutory criteria have been met, including that there are no adequate, approved, and available alternatives.

These vaccines were developed very fast. Are they safe?

It is true that the Pfizer/BioNTech and Moderna vaccines have been developed very quickly. But the technology behind the vaccines is not new. They both are what are called mRNA vaccines, which function very differently than the types of vaccines used in the past. mRNA vaccines, rather than using a weak or ineffective sample of the virus to trigger antibodies  – like in a flu shot – mRNA vaccines instruct your cells to create a harmless protein (called “spike” protein) that your body recognizes as foreign, creating an immune system response. Scientific papers describing this mRNA technology, discovered by Hungarian scientist Katalin Karikó (who oversees mRNA work for BioNTech) were first published in 2005.

Is it safe for a person with a bleeding disorder to receive the COVID vaccine?

If you have a bleeding disorder, there are no contraindications to being vaccinated with either vaccine now available via EUA status for intramuscular administration. It should be noted that, immune tolerance therapy, treatment for hepatitis C, and HIV and other conditions including the use of immunosuppressive agents do not preclude a person from receiving either available vaccine. For patients in a clinical study, vaccination should be reported to the study investigators.

Would I be in a priority group to receive the vaccine with a bleeding disorder?

Since people with bleeding disorders are not at a greater risk of contracting COVID19 or developing a severe form of the disease, they are not considered a priority group. General selection rules will apply for those with a bleeding disorder. Bleeding disorder patients in the risk groups identified by age, state of health, health care or other essential worker will be vaccinated as a priority like others in the general population with the same risks. Priority groups will vary by state.

Is there a particular type of vaccine I should choose?

Currently there is no reason to choose a particular type of vaccine. If you are considering enrolling in a gene therapy clinical trial, you should avoid any vaccines that use a modified adeno-associated virus (AAV) since these viruses are used in gene therapy. No vaccinations currently approved or in development are using AAV viruses. However, vaccines that are using a different virus, adenovirus, are being tested and are unrelated to AAV therefore would not be a problem with enrolling in a gene therapy clinical trial in the future.

Will I have a bleed if I take the vaccination?

The vaccination is administered intramuscularly but the smallest gauge needle should be used (25-27 gauge), if possible. Some vaccines must be administered using the accompanying needle–syringe combination, and so the use of an alternative needle may not be possible or desirable.

It would be preferable for you to infuse with a factor replacement product prior to or right after the vaccination and applying pressure for 10 minutes after the vaccination. Patients receiving emicizumab may be vaccinated by intramuscular injection at any time without receiving an additional dose of FVIII. Patients with von Willebrand Disease or rare bleeding disorders should consult with their hematologist regarding special precautions prior to receiving the vaccination. All rare bleeding disorder patients (including those with thrombocytopenia and/or platelet function disorders) should be vaccinated. Patients on anticoagulants should have prothrombin time testing performed within 72 hours prior to injection to determine international normalized ratio (INR); if results are stable and within the therapeutic range, they can be vaccinated intramuscularly.

Following the vaccination, the area should be monitored for hematoma formation immediately for 10 minutes to reduce bleeding and swelling and by self-inspection 2-4 hours later at home to ensure that there is no delayed hematoma. Discomfort at the injection site is to be expected. Discomfort in the arm felt for 1-2 days after injection should not be alarming unless it worsens and is accompanied by swelling.

Any adverse events should be reported to the physician and any allergic reactions need to be reported immediately to your physician or you need to go to the emergency room. To read more about vaccinations in general please click on this link for NHF’s Medical and Scientific Advisory Council’s recommendations, MASAC Document 221 – Recommendations on Administration of Vaccines to Individuals with Bleeding Disorders.

Should I take the vaccination if I am pregnant or breastfeeding?

Currently, there is limited data on the safety of COVID-19 vaccines for women who are pregnant or breastfeeding, although studies are planned. The Centers for Disease Control and Prevention (CDC) and the FDA have safety monitoring systems in place to capture information about vaccination during pregnancy and will closely monitor reports. Individuals who are pregnant and considering vaccination for COVID-19 are encouraged to speak with their clinicians. According to the CDC, key considerations that should inform these conversations include likely exposure to the virus that causes COVID-19; risks of COVID-19 to the pregnant patients and their fetus; and current knowledge about available vaccines including efficacy, known side effects, and the lack of available data in this population.