Understanding Viral and Bacterial Infections
Learn the key differences between viral and bacterial infections, their symptoms, treatments and when to see a doctor.
Written by: Corey Alexander
Published on: October 23, 2025
As the cooler months approach in Jacksonville and Northeast Florida, respiratory illnesses and infections become more prevalent. From mild viral colds to more serious bacterial conditions, understanding the differences between these infections is essential for getting the right care and protecting your health.
At UF Health Emergency & Urgent Care Centers, we’re here to provide expert guidance and care, right in your community.
What Are Viral Infections?
Viral infections are caused by viruses — tiny agents that invade living cells to replicate. In Northeast Florida, common viral illnesses include the flu, respiratory syncytial virus, or RSV, and the common cold. These infections often spread quickly in schools, workplaces and public spaces, especially during the fall and winter months.
Symptoms of viral infections typically include a runny nose, sore throat, fatigue and mild fever. Most viral illnesses resolve on their own within 10 to 14 days with rest and hydration. However, severe symptoms, such as difficulty breathing, wheezing or a high fever lasting more than three days, may require medical attention.
What Are Bacterial Infections?
Bacterial infections, however, are caused by single-celled organisms that can reproduce independently. In Jacksonville, common bacterial infections include strep throat, bacterial sinus infections, ear infections and skin conditions like cellulitis. These infections can develop as complications from viral illnesses or arise independently.
Certain factors, such as a weakened immune system or chronic health conditions, can increase your risk of developing bacterial infections.
How to Tell the Difference
While viral and bacterial infections can share similar symptoms, there are key differences. Viral infections often develop gradually, such as a cold that starts with a scratchy throat and progresses to a cough and congestion. Bacterial infections, however, tend to appear suddenly and with more intensity. For example, strep throat can cause a severe sore throat and high fever that comes on quickly.
Treatment also varies significantly. Viral infections typically resolve on their own, while bacterial infections often require antibiotics. It’s important to only take antibiotics when prescribed by a doctor. This is to prevent antibiotic resistance, which occurs when bacteria evolve and no longer respond to treatment.
When to Seek Care at UF Health Emergency & Urgent Care Centers
Some viral infections can take a turn and develop into bacterial ones, so it’s important to keep an eye on your symptoms. If things get worse after a few days, like if you’re having trouble breathing, dealing with severe pain, or running a high fever, it’s time to seek medical attention.
You should also come see us if you’re experiencing a stiff neck, a severe headache or persistent vomiting. Swelling or pus from a skin infection are also signs of a bacterial infection.
