State and Local Health Departments

Public health in the United States is mostly a state and local job. Under the Constitution's reserved police powers, states have broad authority to protect health, including requiring vaccinations, which the Supreme Court upheld in Jacobson v. Massachusetts in 1905, and ordering quarantines. Every state has a health department, and about 2,800 local health departments serve counties, cities, and districts, along with tribal health agencies.

Health departments track diseases that doctors and labs must report, investigate outbreaks, inspect restaurants, water systems, and pools, run immunization and maternal and child health programs, license health facilities, and keep birth and death records. Much of their money comes from federal grants, especially from the CDC, which was cut back and reorganized in 2025, leading to layoffs in some departments. The workforce shrank during the 2010s and was strained by the COVID pandemic.

After the pandemic, more than half the states passed laws limiting the emergency powers of health officials or governors, such as mask and closure orders, and some restricted vaccine requirements. Other states expanded their own vaccine advice as federal recommendations changed in 2025, and several regional alliances of states began issuing joint vaccine guidance. The 2025 and 2026 measles outbreaks, the largest in more than 30 years, tested local departments. Supporters of limits say officials overreached during the pandemic, while public health leaders warn that weakened powers and funding leave communities less prepared.