(NEXSTAR) – Recently, it become the most prevalent virus among children in the Denver area. It has contributed to rising pediatric hospitalization rates in San Diego. And no, it’s not COVID-19. It’s RSV.

RSV, or respiratory syncytial virus, causes mild, cold-like symptoms. While most people recover in a week or two, RSV can be serious for infants and older adults, according to the Centers for Disease Control and Prevention. In children younger than 1-year-old, RSV can lead to bronchiolitis and pneumonia.

While hospitals nationwide are reporting high case counts of RSV among children, it isn’t uncommon to see the virus peaking during this time of year. The CDC reports that the “RSV season” typically begins between mid-September and mid-November, peaks from late December to mid-February, and comes to an end between mid-April and mid-May. The only difference is Florida, where the CDC says RSV season starts earlier in the year and lasts longer.

In 2020, when mask-wearing and physical distancing were in effect for COVID-19, there were fewer cases of RSV reported, according to the American Academy of Pediatrics. In spring 2021, when many of those COVID-19 protocols were lifted, RSV cases began to rise again.

“RSV is very contagious and very prevalent in the school system as well as throughout daycare centers and in homes,” said Dr. Reginald Washington, chief medical officer at Rocky Mountain Hospital for Children in Denver, said last week. He noted that while COVID is increasing in its prevalence, RSV is the most prevalent virus impacting kids in his area.

Amidst rising cases of both RSV and COVID-19, how can you tell the difference between the viruses?

What are the symptoms of RSV and COVID-19?

RSV and COVID-19 share many of the same symptoms. They are both viruses that can affect the respiratory system and can be more dangerous for infants and young children, as well as older adults.

Here are the symptoms of RSV, courtesy of the CDC:

  • Runny nose
  • Decrease in appetite
  • Coughing
  • Sneezing
  • Fever
  • Wheezing

These symptoms typically appear in stages, not all at once. In most cases, RSV leads to a cold, which can be followed by bronchiolitis or pneumonia.

Here are the common symptoms of COVID-19:

  • Fever or chills
  • Cough
  • Shortness of breath or difficulty breathing
  • Fatigue
  • Muscle or body aches
  • Headache
  • New loss of taste or smell
  • Sore throat
  • Congestion or runny nose
  • Nausea or vomiting
  • Diarrhea

While COVID-19 brings symptoms more related to the flu, both viruses can cause a fever, coughing, and other respiratory-related signs.

How do I know if I have RSV or COVID-19?

COVID-19, as we know, can be detected with the use of nasal swaps. RSV, on the other hand, is typically diagnosed based on a physical examination by a doctor.

According to the Mayo Clinic, laboratory and imaging tests aren’t usually needed to determine if you have RSV, but they can help to diagnose complications of the virus or rule out other conditions that cause similar symptoms. RSV testing may include blood tests; chest X-rays; a swab of your mouth or nose; and pulse oximetry, which detects oxygen in the blood.

Unlike COVID-19, there is no vaccine for RSV, yet most RSV infections will go away on their own in a week or two. The CDC recommends washing your hands often, covering your coughs or sneezes, avoiding close contact with others, and cleaning frequently touched surfaces to prevent the spread of RSV.

To prevent the spread of COVID-19, the CDC recommends the above practices, as well as wearing a mask when in public indoor settings.