Learn about CDC’s Traveler Genomic Surveillance Program that detects new COVID-19 variants entering the country. Sign up to get travel notices, clinical updates, & healthy travel tips. Measles spreads rapidly in communities that are not fully vaccinated and may pose a risk to international travelers in places not included in the THN. CDC recommends all travelers get fully vaccinated against measles before traveling to any international destination. CDC priorities CDC serves the American public—individuals, families, and communities—who rely on accurate data, health guidance, and preventive measures. As the CDC's databases are no longer maintained with accurate and up-to-date information, a shadow CDC of states and medical societies is forming to fill the vacuum. Travelers Professionals and Vaccine Communications Information for Health Care Providers CDC vaccine and vaccination information for U.S. health care providers. To make science and data easier for broad audiences to interpret, CDC is translating science into practical, easy to understand policy by clarifying and presenting scientific language so that anyone can understand it and standardizing guideline development across the agency. The Health Topics A-Z Index lists topics with relevance to a broad cross-section of CDC.gov’s audiences. The items are representative of popular topics, frequent inquiries, or have critical importance to CDC’s public health mission. Global Health Security CDC is a critical part of the U.S. government-wide effort to promote global health security. How to Protect Yourself and Others Tools and Resources Interim Clinical Considerations Clinical Care Quick Reference Infection Control Guidance Containing COVID-19 in Non-U.S. Healthcare Settings Surveillance and Data Analytics SARS-CoV-2 Laboratory Biosafety Guidelines Antibody Seroprevalence CDC's Role in Tracking Variants SARS-CoV-2. The Centers for Disease Control and Prevention (CDC) collaborates to create the expertise, information, and tools that people and communities need to protect their health through health promotion, prevention of disease, injury and disability, and preparedness for new health threats.