Vaccine Safety

Johnson & Johnson’s Janssen COVID-19 Vaccine: CDC and FDA have recommended that use of Johnson & Johnson’s Janssen (J&J/Janssen) COVID-19 Vaccine resume in the United States, effective April 23, 2021. However, women younger than 50 years old especially should be aware of the rare risk of blood clots with low platelets after vaccination, and that other COVID-19 vaccines are available where this risk has not been seen. If you received a J&J/Janssen vaccine, here is what you need to know. Read the CDC/FDA statement.

Get Started with v-safe
Get Started with v-safe, together

Use your smartphone to tell CDC about any side effects after getting the COVID-19 vaccine. You’ll also get reminders if you need a second vaccine dose.

The United States currently has the safest vaccine supply in its history. The nation’s long-standing vaccine safety system ensures that vaccines are as safe as possible.

Vaccine Safety is a vital part of the nation’s response to the COVID-19 pandemic. As vaccines are developed and become available, the public’s knowledge of their safety, both initially and during extended use, is an important part of a successful national vaccination effort.

CDC’s Immunization Safety Office works to communicate timely and transparent information about the safety of vaccines to public health officials, healthcare providers, and the public. The office conducts vaccine safety monitoring and clinical research to help keep vaccines safe.

Report a Possible Health Problem following
Vaccination to VAERS

Everyone is encouraged to report possible health problems (adverse events) after vaccination to the Vaccine Adverse Event Reporting System (VAERS). Healthcare providers and vaccine manufacturers are required to report certain health events.

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Request a COVID-19 CISA Clinical Consultation

Healthcare providers or health departments in the United States can request a consultation for complex COVID-19 vaccine safety questions from CISA COVIDvax.

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COVID-19 Vaccine Safety
Vaccine and syringe injection It use for prevention, immunization and treatment from COVID-19

Vaccine Safety is a top priority while CDC and federal partners work to make COVID-19 vaccines available.

VAERS
screenshot top of VAERS hompage

The Vaccine Adverse Event Reporting System (VAERS) serves as the nation’s early warning system to monitor for potential vaccine safety problems. Anyone can report possible health problems to VAERS.

VSD
VSD map

The Vaccine Safety Datalink (VSD) is a collaboration between CDC and 9 health care organizations that conducts active vaccine safety monitoring and research.

CISA Project
CISA Project Map

The Clinical Immunization Safety Assessment (CISA) Project is a partnership between CDC and 7 medical research centers that provides expert consultation and conducts clinical research on vaccine-associated health risks.

COVID-19 Vaccine Information

For clinicians:
COVID-19 Vaccine Product Information
Key information for each specific COVID-19 vaccine including administration, storage and handling, safety, and reporting.

For the general public:
COVID-19 Vaccine Information Overview
Overview of what everyone should know about the different COVID-19 vaccines.
COVID-19 vaccine factsheets:
COVID-19 Vaccine Emergency Use Authorization (EUA) Fact Sheets for Recipients and Caregivers
Fact sheets for each COVID-19 vaccine authorized under the Emergency Use Authorization (EUA).