How to know if you have flu, COVID, RSV: symptoms, prevalence, signs

• Many seasonal diseases are spreading, not just flu, COVID and RSV.
• Many have overlapping symptoms, but there are few clear ways to distinguish the different diseases.
• If you have a fever, plus a headache or cough, doctors recommend getting tested for the flu and COVID.

USA is sick. Federal health data shows that the country is hot right now with lots of fevers, sore throats and coughs popping up from coast to coast.

Most current illnesses are flu. Waste water surveillance also suggests that COVID is on the rise after Thanksgiving, and RSV — which sent babies and toddlers to urgent care for months — still circulates heavily.

But there are many other diseases besides the “triple epidemic” of flu, COVID and RSV that are contributing to this year’s earlier-than-usual bout of seasonal flu.

“There is a lot of viral garbage out there,” infectious disease expert dr. William Schaffnerfrom Vanderbilt University School of Medicine, told Insider.

Here are some of the most common culprits currently at work, according to infectious disease experts who conduct virus testing at major medical centers across the U.S., as well as federal disease monitors at the Centers for Disease Control and Prevention:

Apart from guesswork based on prevalence, it is not so easy to find out exactly which disease you contracted.

“Fever, muscle aches, cough, headache, it’s going to be common,” Dr. Roy Gulick, chief of infectious diseases at New York-Presbyterian and Weill Cornell Medicine, told Insider. “You really can’t tell the difference between the flu and COVID.”

However, there are some clear symptoms that can help distinguish one disease from another. Paying attention to how quickly your illness develops and which symptoms are most pronounced can help you assess which seasonal illness you may have:

If you think you might have the flu or COVID, it’s worth getting tested. If you catch the infection early enough, antiviral treatments are available that can shorten the course of your infection, but also make it milder.

“If people have a fever or a cough, a headache, they really should be tested for both the flu and COVID,” Gulick said. This is especially important for older adults, who account for the vast majority of deaths from COVID and influenza. “You need to be screened, treated and diagnosed early.”

However, if your illness isn’t the flu or COVID, there’s often not much that can be done other than to wait for your immune system to finish its fight and stay as comfortable and healthy as possible in the meantime.

“Knowing it’s RSV isn’t really going to change anything we do,” pediatrician Manuela Murray, medical director of the University of Texas Medical Branch’s Pediatric Urgent Care Center, told Insider. “We really don’t have any drugs that help.”

The same is true for many other viruses. For most of them, the doctor’s orders are to rest, hydrate, and take pain and fever medication to ease your pain.