Gone are the days of hallmark COVID-19 symptoms. While loss of taste and smell, and persistent cough were once tell-tale signs of the respiratory infection, symptoms today vary widely, with tests being the only sure-fire way to confirm a diagnosis, physicians told NBC News in a June 27 report. 

“Every week, we test someone for COVID who I didn’t think had it who tests positive,” Steven Furr, MD, president of the American Academy of Family Physicians and family physician in Jackson, Ala., told the news outlet. “Then we have others who I’m pretty sure have COVID who test negative … It’s really hard to separate COVID from any other respiratory illness right now.” 

Physicians say patients who end up testing positive have symptoms that “vary from A to Z and beyond.” Some do have classic respiratory virus symptoms: Sore through, congestion and low-fever. Others have gastrointestinal symptoms, but nearly no respiratory symptoms. 

Sans one major signal, physicians have largely abandoned “you probably have COVID” diagnoses in favor of test-confirmed diagnoses only. 

Shifts in symptom patterns have occurred over time as people gained exposure, and thus, some level of immunity to the virus. Virus mutations also play a role, experts say. 

In the spring, COVID-19 activity in the U.S. hit its lowest levels since the pandemic began. As of June 25, the CDC said infections “are growing or likely growing” in most states, stable or uncertain in five states, and “declining or likely declining in 1 state or territory.” Hospitalization and death rates remain low, though test positivity and emergency department visits related to COVID have risen in recent weeks. 

On June 27, the CDC recommended everyone 6 months and older receive an updated vaccine. Officials have said new shots are expected to be available in August and September, according to NBC. Earlier this month, the FDA instructed vaccine manufacturers to target JN.1, a strain that dominated this past winter. Within a week, the agency circled back with manufacturers to say a specific offshoot of the JN.1 lineage — KP.2 — may be a better target, since it now makes up a higher proportion of cases.

KP. 3, another JN. 1 relative, currently makes up about 33% of cases in the U.S., followed by KP. 2 at around 21%, and LB.1 at 18%.