What is Influenza (Flu) Surveillance?

Each year, DPH and U.S. public health experts monitor influenza (flu) and other diseases. This activity is called disease surveillance.

Flu surveillance allows DPH and the Centers for Disease Control and Prevention (CDC) to see what impact flu is having on the health of residents. Learn more about how surveillance helps us.

South Carolina Flu Activity

Flu Watch

DPH compiles the South Carolina flu data for a weekly surveillance report called, Flu Watch. This report is shared each Wednesday.

Week of December 1 - December 7, 2024 (MMWR Week 49)

• View Latest Flu Watch - (pdf)
• View 2024-2025 Weekly Surveillance Reports
  For the current flu season (2024-2025), positive rapid antigen tests are not required to be reported. An evaluation of the flu surveillance system shows removing this reporting requirement does not compromise the virologic surveillance of flu in South Carolina

Additional Resources:

• SC Flu Surveillance Components and Definitions page
• Reporting Forms and Worksheets
• View Past Surveillance Reports

Biweekly Flu Vaccination Data

As part of statewide monitoring of one of the most active flu seasons (2022-2023) in recent years, DPH has begun tracking flu vaccination numbers and will provide those numbers every two weeks, beginning Wednesday, Nov. 23.

• View Biweekly Flu Vaccination Data
• View Seasonal Flu Vaccination Trend Data

How Does Flu Surveillance Help Us?

Surveillance helps us to:

• Determine whether the flu virus is what is causing flu-like symptoms (Sometimes other conditions have flu-like symptoms but are not flu);
• Understand which new flu viruses are circulating in South Carolina (The types of flu virus that infect people often change from one flu season to the next.);
• Tell us when the flu virus first appears in the state and also when it decreases;
• Determine where in the state the flu virus is circulating; and
• Understand what types of vaccines are most likely to succeed the following year.

In South Carolina, flu surveillance consists of several components. Each component provides different types of information about flu; together, they create a complete overview of flu activity in the state.

U.S. and International Flu Activity

Visit the Centers for Disease Control and Prevention's (CDC) website for national statistics on flu.

Visit the World Health Organization's (WHO) website for global flu activity updates.