Emergency Preparedness and Vaccine Safety

CDC’s Immunization Safety Office (ISO) prepares for emergencies by ensuring that robust systems are in place to rapidly monitor vaccine safety in the event of an emergency vaccination program.

During an emergency involving mass vaccination, monitoring vaccine safety is important because:

• The vaccines being used might be new. With any new vaccine, initial safety data might be limited. In this situation it will be important to closely monitor safety to detect unexpected or concerning patterns.
• Large numbers of vaccines might be given in a short period of time, and therefore more adverse events (possible side effects) might be reported to the Vaccine Adverse Event Reporting System (VAERS).
• Public awareness of vaccination programs during an emergency might stimulate reporting to VAERS resulting in higher volume reporting than during non-emergency situations

Vaccine Safety Tools in an Emergency

• V-safe is a new smartphone-based, after-vaccination health checker for people who receive COVID-19 vaccines. V-safe uses text messaging and web surveys from CDC to check in with vaccine recipients following COVID-19 vaccination. V-safe also provides second vaccine dose reminders if needed, and telephone follow up to anyone who reports medically significant (important) adverse events
• VAERS accepts vaccine adverse event reports from patients, parents, healthcare professionals, vaccine manufacturers and others.  CDC and FDA scientists review reports and use statistical techniques to detect unusual or unexpected patterns that might indicate a vaccine safety problem.
• The Clinical Immunization Safety Assessment (CISA) Project is a national network of vaccine safety experts which addresses vaccine safety issues, conducts clinical research and assesses complex clinical adverse events following vaccination.
• The Vaccine Safety Datalink (VSD) project gathers information on vaccines given to members of certain health care organizations around the country. A system called rapid cycle analysis allows CDC to address vaccine-associated health problems very quickly.
• Vaccine Safety Coordinators positioned in 62 health departments in states, territories, large urban areas and freely associated states carry out vaccine safety and emergency preparedness activities while coordinating with CDC.

Vaccine Safety Standard Operating Procedures For COVID-19

In the COVID-19 response, Standard Operating Procedures (SOPs) have been developed to help public health professionals perform tasks related to COVID-19 vaccine safety and monitoring. These SOPs also provide guidance to CDC staff when something may seem out of the ordinary or does not have a specific set of instructions. CDC has multiple vaccine safety monitoring systems in place to help keep COVID-19 vaccines safe. SOPs to monitor COVID-19 vaccines have been developed for each of the systems.

Learn more about Ensuring the Safety of COVID-19 Vaccines in the United States

These SOPs are living documents and subject to updates as needed.

Examples of Past Vaccine Safety Emergency Responses