Recognized on October 13, World Thrombosis Day focuses attention on the often overlooked and misunderstood condition of thrombosis.

With thousands of educational events in countries around the world, World Thrombosis Day and its partners place a global spotlight on blood clots as an urgent and growing health problem. Our mission supports the World Health Assembly global target of reducing premature deaths by non-communicable disease by 25 percent by 2025, as well as the World Health Organization’s 13th General Programme of Work 2019–2023, the Montevideo Roadmap 2018-2030 on NCDs and the Political Declaration of UNGA’ Third High-level Meeting on NCDs.

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Our Mission

We strive to reduce death and disability caused by thrombosis.

World Thrombosis Day, a campaign of the International Society on Thrombosis and Haemostasis (ISTH), seeks to increase global awareness of thrombosis, including its causes, risk factors, signs, symptoms, evidence-based prevention and treatment. Ultimately, we strive to reduce the death and disability caused by the condition.

Global Objectives

Working Together to Save Lives


Highlight the burden of disease (thrombosis in general) and highlight the need for action, specifically underscoring the unrecognized threat and serious consequences (morbidity and mortality) related to venous thromboembolism (VTE) and atrial fibrillation (AFib).


Increase public awareness of the significance, risks, signs and symptoms of thrombosis, specifically VTE and AFib as an important cause of thromboembolic stroke.


Empower individuals to talk with their healthcare providers about their risk for thrombosis and appropriate prevention. Empower individuals to seek immediate medical attention if they have signs and symptoms.


Galvanize organizations in countries across the globe to conduct appropriate and aligned campaigns in their regions.


Advocate for “systems of care” to properly prevent, diagnose and treat VTE and AFib.

World Thrombosis Day Leadership

Meet the World Thrombosis Day Steering Committee

World Thrombosis Day is guided by a Steering Committee of international medical experts in the fields of hematology, thrombosis and hemostasis, vascular and general internal medicine, and public health. The campaign is led by the International Society on Thrombosis and Haemostasis (ISTH) in collaboration with thousands of international and national professional health, medical organizations and health advocates.

Meet the Committee
Campaign Team

Samantha (Sam) Nelson

Campaign Manager

Barbara Krolak

Marketing Manager

Melissa DiMercurio

Media Relations Manager

“As a blood clot survivor myself, my #WTDWhy is to make sure that all blood clot survivors feel informed, educated and know how strong and resilient they are!”

— Sam Nelson, Campaign Manager

Impact Report
Each year, the World Thrombosis Day campaign is evaluated and its reach and influence are analyzed.
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