With the approval of two vaccines, many vaccine safety monitoring systems watch for possible side effects. This continued monitoring can pick up on side effects that may not have been seen in clinical trials. V-SAFE is a new smartphone-based, after-vaccination health checker for people who receive COVID- 19 vaccines. V-SAFE will use text messaging and web surveys from CDC to check in with vaccine recipients for health problems following COVID-19 vaccination. The system also will provide telephone follow up to anyone who reports medically significant side effects. Learn more about V-SAFE here (PDF) and here (PDF).