Related Experiment Video

Updated: Sep 30, 2025

An Optimized Hemagglutination Inhibition HI Assay to Quantify Influenza-specific Antibody Titers
06:34

An Optimized Hemagglutination Inhibition HI Assay to Quantify Influenza-specific Antibody Titers

Published on: December 1, 2017

36.7K

Thrombotic events following Covid-19 vaccines compared to Influenza vaccines

Marcelo Gabriel Vallone1, Andre Luis Falcón1, Horacio Matias Castro2

  • 1Internal Medicine Section, Hospital Italiano de Buenos Aires. J.D. Perón 4190, Ciudad Autónoma de Buenos Aires, C1181ACH, Argentina.

European Journal of Internal Medicine
|March 15, 2022
PubMed

Insights

COVID-19 vaccination was associated with a higher incidence of thrombotic events compared to influenza vaccination. This finding requires careful consideration alongside vaccine benefits and COVID-19

Area of Science:

  • Epidemiology
  • Vaccinology
  • Thrombosis Research

Background:

  • The risk of thrombotic events following COVID-19 vaccination remains an important public health question.
  • Understanding this risk is crucial for informed vaccination strategies.

Purpose of the Study:

  • To investigate the incidence of thrombotic events in individuals who received COVID-19 vaccines.
  • To compare this risk against a historical control group vaccinated with influenza vaccine.

Main Methods:

  • A retrospective cohort study was conducted comparing adults vaccinated with COVID-19 vaccines (Sputnik, AstraZeneca, Sinopharm) between January and May 2021.
  • A control group received influenza vaccine between March and July 2019.
  • The primary outcome was the cumulative incidence of symptomatic thrombotic events within 30 days post-vaccination.

Main Results:

  • The study included 29,918 patients in the COVID-19 vaccine group and 24,753 in the influenza vaccine group.
  • The incidence of thrombotic events was 12 per 10,000 for COVID-19 vaccines versus 6 per 10,000 for influenza vaccine (p=0.022).
  • A statistically significant increase in thrombotic events was observed in the COVID-19 vaccination group.

Conclusions:

  • COVID-19 vaccination showed a significant association with an increased risk of thrombotic events compared to influenza vaccination.
  • Clinical interpretation must balance these findings with the proven benefits of vaccination and the thrombotic risks of COVID-19 infection.
  • Further research may be needed to fully elucidate the implications.
Abstract

Keywords:
Covid-19Thrombotic eventsVaccines

More Related Videos

Rapid Molecular Detection and Differentiation of Influenza Viruses A and B05:38

Rapid Molecular Detection and Differentiation of Influenza Viruses A and B

Published on: January 30, 2017

15.9K
Use of an Influenza Antigen Microarray to Measure the Breadth of Serum Antibodies Across Virus Subtypes08:52

Use of an Influenza Antigen Microarray to Measure the Breadth of Serum Antibodies Across Virus Subtypes

Published on: July 26, 2019

8.3K

Related Concept Videos

Vaccinations01:51

Vaccinations

Overview
45.5K
Venous Thrombosis III: Interprofessional Care01:29

Venous Thrombosis III: Interprofessional Care

Venous thrombosis requires effective prevention and treatment strategies to improve patient outcomes and reduce potential complications.Prevention StrategiesHealthcare providers must prioritize preventing venous thromboembolism (VTE) for all adult patients upon admission. Interventions depend on bleeding and thrombosis risk, medical history, current medications, diagnoses, planned procedures, and patient preferences. Patients on bed rest should change positions every two hours and, if not...
42
Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants01:18

Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants

Oral anticoagulants are vital tools in preventing and treating blood clotting disorders. This diverse class of medications can be categorized as vitamin K antagonists, exemplified by warfarin, and direct thrombin inhibitors (DTIs), such as dabigatran, as well as factor Xa inhibitors, including rivaroxaban.
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...
1.4K
Anticoagulant Drugs: Low-Molecular-Weight Heparins01:30

Anticoagulant Drugs: Low-Molecular-Weight Heparins

Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
963
Venous Thrombosis II: Clinical Manifestations and Diagnostic Studies01:20

Venous Thrombosis II: Clinical Manifestations and Diagnostic Studies

The key difference between Superficial Vein Thrombosis (SVT) and Deep Vein Thrombosis (DVT) lies in their location and severity.Clinical ManifestationsSVT typically presents with localized pain, tenderness, and redness along the course of a superficial vein, often accompanied by a palpable, cord-like structure under the skin. This condition is usually less dangerous than DVT but can be uncomfortable and may lead to complications such as cellulitis or, rarely, a clot extension into the deep...
51
Venous Thrombosis I: Introduction01:30

Venous Thrombosis I: Introduction

Venous thrombosis, the most common disorder of the veins, involves the formation of a thrombus or blood clot associated with vein inflammation. It can be classified as either superficial vein thrombosis or deep vein thrombosis.Superficial Vein Thrombosis: This involves the formation of a thrombus in a superficial vein, usually the greater or lesser saphenous vein. Though less severe than deep vein thrombosis (DVT), SVT can lead to complications if untreated.Deep Vein Thrombosis (DVT): This...
56