Covid rates are still rising across most of the country, fueled by the highly contagious new variants of the virus —KP.2 and KP.3 and LB.1. As of July 18, the highest levels of Covid are in the Western states, although there are no areas of the U.S. where rates are noticeably dropping, according to CDC wastewater data.
At least 21 states have very high levels of Covid, the data shows.
“You have a very, very transmissible variant, probably one of the most transmissible we’ve had,” said Dr. Peter Chin-Hong, a professor of medicine and infectious disease specialist at the University of California, San Francisco. “We have a lot of population immunity, but it doesn’t mean that there isn’t a lot of chaos.”
But people who test positive for Covid don’t need to isolate for five days, according to recent guidance from the Centers for Disease Control and Prevention.
This is the first major wave since the CDC updated its Covid guidance, said Katelyn Jetelina, an epidemiologist who tracks illnesses on her website, Your Local Epidemiologist. She recommends isolating until an at-home Covid test turns negative, which could be anywhere from three to 15 days.
Yet, with fewer people testing for Covid, experts say it’s more important than ever to pay attention to symptoms.Since March, the CDC’s guidance has matched advice for flu and other respiratory illnesses: Stay home when you’re sick, but you can return to work or school once you’re feeling better and you’ve been without fever for 24 hours.
“The guidelines reflect a number of things, including the fact that we generally are overall shedding for less time now,” Bill Hanage, an associate director at the Center for Communicable Disease Dynamics at Harvard University, said. “And there’s more of a link between symptoms” and being contagious.
Because most Americans have already either had a version of the virus or have had several vaccines or boosters — or have had Covid and are also vaccinated — it’s hard to separate Covid symptoms from other respiratory illnesses without testing. Right now, chances are, if you have upper respiratory symptoms — sniffles or congestion — or a cough, it could be Covid.
According to the CDC, someone with Covid can go back to normal activities when symptoms have been getting better for at least 24 hours and no fever even without taking fever-reducing medication like acetaminophen or ibuprofen.
Then for the next five days, take precautions such as wearing a mask in crowded indoor situations.
The majority of viral spread happens when people are the sickest.
“As the days go on, less virus spreads,” CDC Director Dr. Mandy Cohen said in an interview this year.
The CDC guidance is for the general public only, and does not include isolation guidelines in hospital settings, which is generally 10 days.
Covid symptoms
For people who have been through at least one Covid infection, or are up to date with the vaccines, symptoms often resemble a common cold or other respiratory illness.
Common Covid symptoms include:
- Runny nose
- Fatigue and muscle aches
- Sore throat
- Cough
- Mild fever
- Nausea or diarrhea
There's not really a major sign that indicates Covid, doctors say, so the only way to know for sure is to take a test.
When should I test for Covid? How often?
The original guidance from the CDC was to test approximately five days after exposure because it took that long before the virus became detectable in the body. Now, with high levels of prior exposure, some people could feel symptoms a day or two after exposure, not because the virus is growing more quickly but because the immune system recognizes the virus and responds symptomatically, Michael Mina, an epidemiologist and former professor of immunology and infectious diseases at the Harvard T.H. Chan School of Public Health, said.
While many people aren't bothering to test now — tests aren't free anymore — Mina advises taking an at-home test on the third day after symptoms begin. If it's negative, test again the next day.
"If I had only two tests, that's where I'd stop testing," Mina said. "If positive, you don't need more tests. My best educated guess is, assume you're infectious for five days after testing positive."
In a prior study, Mina said that up to 50% of people were still infectious a week or eight days after symptoms begin and up to 20% were still contagious up to nine days later.
While people's immunity is doing a better job than a year ago, Mina believes many people could still be contagious five days after symptoms begin.
The experts recognize that most people will be ready to get back to work or school quickly after they feel better. What's most important is to be careful around people who may be immunocompromised or elderly.
"You don’t want people to be locking themselves in their bedrooms for five days," said Hanage. That said, "there are some contexts where you really would want to be more careful, including giving it to somebody who’s vulnerable for whatever reason."
