Final answer:
The Centers for Disease Control and Prevention (CDC) is responsible for public health databases at the national level in the United States.
Step-by-step explanation:
The organization responsible for public health databases at the national level in the United States is the Centers for Disease Control and Prevention (CDC). The CDC oversees the National Notifiable Disease Surveillance System (NNDSS), which monitors diseases considered to be of public health importance. Physicians treating patients with notifiable diseases are legally required to submit reports to the CDC.