COVID-19 Healthcare Quality and Worker Safety Information
Selected Adverse Events Reported after COVID-19 Vaccination - CDC is providing timely updates on the following adverse events of interest:
Anaphylaxis after COVID-19 vaccination - Anaphylaxis after COVID-19 is rare and has occurred at a rate of approximately 5 cases per one million vaccine doses administered. Anaphylaxis, a severe type of allergic reaction, can occur after any kind of vaccination. If it happens, healthcare providers can effectively and immediately treat the reaction. Learn more about COVID-19 vaccines and allergic reactions, including anaphylaxis.
CDC scientists have conducted detailed reviews of cases of anaphylaxis and made the information available to healthcare providers and the public:
- Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine
- Reports of Anaphylaxis After Receipt of mRNA COVID-19 Vaccines in the US-December 14, 2020-January 18, 2021
- Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Moderna COVID-19 Vaccine- United States, December 21, 2020-January 10, 2021
- Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine - United States, December 14-23, 2020
To learn more, please visit: Selected Adverse Events Reported after COVID-19 Vaccination | CDC
Post-COVID Conditions: CDC Science: How CDC is using science to learn more about post-COVID conditions (or long COVID) - CDC is analyzing healthcare data, partnering with clinicians, and working with researchers to learn more about post-COVID conditions (Long COVID).
Post-COVID conditions (PCC, or Long COVID) are a wide range of new, returning, or ongoing health problems people can experience four or more weeks after first being infected with the virus that causes COVID-19. To learn more, please visit: Post-COVID Conditions: CDC Science | CDC
Related Content

Feb 04, 2021
A Peculiar Case of Pediatric Subdural Empyema
Subdural empyemas are associated with significant morbidity and mortality if not recognized and treated promptly. The condition leads to purulent fluid collections between the dura and arachnoid mater. In infants, meningitis is the most common cause; in older children, sinusitis and otitis media are typically the primary sources.


Dec 29, 2020
Financial Impacts of ED Observation Units: Literature and Strategies Review
The emergency department observation unit (EDOU) is a specialized unit designed for efficient, ongoing medical treatment, assessment, and reassessment of patients before the decision can be made to discharge or admit. Do they end up costing patients more?