As colder weather arrives, winter’s “triple-demic” is expected to emerge with rising cases of influenza (flu), COVID-19 and respiratory syncytial virus (RSV).
The simultaneous rise in all three illnesses strains health care systems due to increased patient numbers. The 2024-25 flu season was the leading contributor to the overall impact, with weekly rates of laboratory-confirmed flu hospitalizations reaching their highest levels since the 2010-11 season.
Florida State University’s Dr. George Rust is a professor and co-director at the Center for Medicine and Public Health Policy and Practice, and also serves as the FSU College of Medicine Medical Director. Rust is a family physician, public health professional, author and health outcomes researcher. He recently authored the book “Healing in a Changing America,” offering a candid guide to self-discovery and organizational effectiveness in the pursuit of health equity.
In 2025, Rust has been involved in expert pitches that include the H5N1 bird flu, the measles outbreak and flu season. He has won numerous awards for his teaching and service and is board-certified in both family practice and preventive medicine. He also serves as the medical director for six local county public health departments.
Rust believes the occurrence of all three illnesses at once poses an elevated risk during the colder months.
“Many people get sick and just stay home miserable for a few days or a week, but some people get sicker,” Rust said. “Public health surveillance systems notice higher rates of emergency room visits, hospitalizations and roughly 45,000 deaths per year due to respiratory infections during this season. Even healthy people can get pneumonia from these respiratory infections. People who have chronic lung disease, cancer, heart failure or weakened immune systems are at risk for being hospitalized or dying from these diseases.”
Rust also believes protective strategies can mitigate the harsh effects of these illnesses.
“Thankfully, we have excellent vaccines for all three conditions,” Rust added. “Because the strains of influenza circulating around the world change each year, an annual flu shot is needed and is recommended for all adults and for children over age 6 months.”
Media inquiries on Dr. Rust’s perspective and guidance for the winter “triple-demic” may reach out to him via email at George.rust@med.fsu.edu.
Dr. George Rust, professor and co-director, FSU Center for Medicine and Public Health Policy and Practice
Why do the colder months pose the greatest risk for influenza, COVID-19 and RSV?
There are several reasons for the increase in respiratory infections in the winter. Cold, dry air or even indoor heated air (also dry) can help the virus to hang in the air longer and remain alive on surfaces longer. In addition, drying out the lining of the nose can decrease mucous production that traps germs, and can also diminish the response of immune cells in the nose and respiratory tract. When it’s cold, people tend to stay indoors more. We often like to go home for the holidays and attend holiday gatherings. We travel and carry our germs with us, and then we share them with others in crowded indoor settings.
What are the best preventive measures to avoid all three illnesses?
Flu shots on average offer 40-60% effectiveness. This year, the H3N2 strain is circulating and was not covered in flu vaccine formulations. We also need updated COVID-19 shots to cover the latest strains. RSV vaccines are given only once. The RSV vaccine is recommended for all people over age 75 and for people age 50-74 who have weakened immune systems or certain chronic diseases. Keep in mind that we get vaccines not just to protect ourselves, but to protect our family and our neighbors, especially those who are most vulnerable. Community spread decreases when many people get vaccinated.
The vaccines are not perfect, however. Disinfecting commonly touched surfaces and frequent handwashing can help. Medically vulnerable people should consider wearing a mask. Avoiding contact with sick people is important, which means that if you get a respiratory infection, you shouldn’t go to school or work.