Though symptoms may vary by variant, according to the Centers for Disease Control and Prevention (CDC), epidemiologists haven’t linked select symptoms to specific variants. If you have COVID more than once, even your individual symptoms may differ from infection to infection.

That said, with the “quad-demic” of COVID, flu, respiratory syncytial virus (RSV), and norovirus making the rounds this winter, how do you know which illness your symptoms reflect? Testing, a process with which you’ve likely become intimately familiar these last few years, is the only way to know for sure.

Free, rapid COVID tests—four per household—are still available at COVIDtests.gov. They’re also sold at countless stores and online retailers. Some over-the-counter and laboratory tests can use a single sample to determine whether you have COVID, influenza A, influenza B, and/or RSV. A norovirus test must be completed by a health care professional, and there’s no test for the common cold.

What are the symptoms of COVID?

COVID symptoms may vary based on your vaccination status, the CDC notes, and new symptoms may emerge as the coronavirus continues to evolve. For now, these are among the common indicators, which range from mild to severe:

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

The following symptoms are less common, according to the World Health Organization:

• Rash on skin, or discoloration of fingers or toes
• Red or irritated eyes

Not everyone who tests positive for COVID will exhibit symptoms, but those who do may notice symptoms two to 14 days after exposure to the virus. People with COVID can be contagious anywhere from one to two days before and eight to 10 days after their symptoms begin, the CDC says. You can still spread the virus to others if you’re asymptomatic.

Which COVID symptoms require emergency care?

If you or someone in your care shows any of the following symptoms, the CDC urges seeking emergency medical care:

• Inability to wake or stay awake
• Lips, skin, and nail beds that appear pale, blue, or gray
• New confusion
• Persistent pain or pressure in the chest
• Trouble breathing

How do I treat my COVID symptoms?

While over-the-counter medications such as ibuprofen and acetaminophen can provide relief for most people with mild symptoms, the CDC says, it’s a good idea to discuss treatment options with your doctor as soon as you test positive for COVID.

People with certain medical conditions ranging from asthma to cancer to obesity are at high risk of severe COVID infection. People who have never gotten a COVID vaccine or aren’t up to date on their vaccinations are also at increased risk. Your health care provider will determine whether prescription antiviral medication such as Paxlovid (nirmatrelvir with ritonavir) or Lagevrio (molnupiravir) is right for you. To be effective, these treatments must be started within five to seven days of symptom onset.

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