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ASH Releases Real-Time Resource to Guide Clinicians in Awareness of Rare Clotting Condition After COVID-19 Vaccination

(WASHINGTON, Apr. 15, 2021) — Today, the American Society of Hematology (ASH) released a new resource to guide clinicians around the world in recognizing and treating an extremely rare clotting condition appearing to occur after immunization with the Johnson & Johnson or AstraZeneca COVID-19 vaccines.

The resource, which will be updated in real-time, reports on a syndrome characterized by severe blood clots and low platelet counts known as vaccine-induced immune thrombotic thrombocytopenia (VITT). To date, out of more than 6.8 million doses of the Johnson & Johnson vaccine administered in the U.S., six individuals have suffered this complication. The condition has also been reported in rare instances after the AstraZeneca vaccine, which is not yet available in the U.S. but has been administered widely in Europe and Canada.

Key points about Vaccine-induced Immune Thrombotic Thrombocytopenia: Frequently Asked Questions:

  • This resource aims to bring awareness of VITT to all providers on the front lines against COVID-19 – emergency room physicians, primary care providers, and urgent care providers in addition to hematologists – who should be mindful of this possible complication and act rapidly if a patient has suspected VITT.
  • It helps health care providers recognize the signs and symptoms, which typically occur four to 20 days following vaccination and should not be confused with more typical post-vaccine symptoms that occur in the first 24-48 hours.
  • It outlines the steps that should be taken to make a diagnosis.

While VITT is exceedingly rare, ASH recognized the importance of informing all clinicians on the frontlines of treating COVID-19, and rapidly convened a panel of expert hematologists from all over the world to offer information about the condition.

Based on current information, the panel’s consensus is that the risk of COVID-19, including thrombosis, far outweighs the extremely rare risk of VITT associated with highly efficacious vaccines. Providers can encourage patients being vaccinated against COVID-19 to monitor, and seek medical attention for rare instances of severe symptoms.

ASH is maintaining www.hematology.org/COVID19 as a medium to exchange information to assist hematologists in navigating the COVID-19 public health crisis.

The American Society of Hematology (ASH) (www.hematology.org) is the world’s largest professional society of hematologists dedicated to furthering the understanding, diagnosis, treatment, and prevention of disorders affecting the blood. For more than 60 years, the Society has led the development of hematology as a discipline by promoting research, patient care, education, training, and advocacy in hematology. ASH publishes Blood  (www.bloodjournal.org), the most cited peer-reviewed publication in the field, and Blood Advances (www.bloodadvances.org), an online, peer-reviewed open-access journal.

Leah Enser, American Society of Hematology
[email protected]; 202-552-4927