The newest version, which was posted on Monday, amended the agency’s guidance to say that people who have been in close contact with an infected individual — typically defined as being within six feet of a person with the coronavirus and for at least 15 minutes — “do not necessarily need a test” if they do not have symptoms. Exceptions, the agency noted, might be made for “vulnerable” individuals, or if health care providers or state or local public health officials recommend testing.
“Wow, that is a walk-back,” Dr. Butler-Wu said. “We’re in the middle of a pandemic, and that’s a really big change.”
Dr. Butler-Wu said she was concerned that the guidelines would be misinterpreted as implying that people without symptoms were unable to pass the coronavirus on to others — a falsehood that experts had been trying for months to dispel. “If people are getting exposed, and they’re not getting tested, and they’re not isolating, that’s a huge problem,” Dr. Kuppalli said.
By the C.D.C.’s own estimates, roughly 40 percent of people infected with the coronavirus may never go on to develop symptoms, remaining asymptomatic for the duration of their tenure with the virus. These numbers are tentative — and ironically can’t be confirmed without more testing of people who appear entirely healthy.
Although researchers remain unsure how often asymptomatic people unwittingly transmit the coronavirus, studies have shown that the silently infected can carry the virus in high amounts. The evidence is more clear-cut for pre-symptomatic people, in whom virus levels tend to peak just before illness sets in — a period when these individuals might be mingling with their peers, seeding superspreader events. Notably, experts can’t distinguish asymptomatic people from those who are pre-symptomatic until symptoms do or don’t appear.
The Coronavirus Outbreak ›
Frequently Asked Questions
Updated August 24, 2020
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What are the symptoms of coronavirus?
- In the beginning, the coronavirus seemed like it was primarily a respiratory illness — many patients had fever and chills, were weak and tired, and coughed a lot, though some people don’t show many symptoms at all. Those who seemed sickest had pneumonia or acute respiratory distress syndrome and received supplemental oxygen. By now, doctors have identified many more symptoms and syndromes. In April, the C.D.C. added to the list of early signs sore throat, fever, chills and muscle aches. Gastrointestinal upset, such as diarrhea and nausea, has also been observed. Another telltale sign of infection may be a sudden, profound diminution of one’s sense of smell and taste. Teenagers and young adults in some cases have developed painful red and purple lesions on their fingers and toes — nicknamed “Covid toe” — but few other serious symptoms.
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Why does standing six feet away from others help?
- The coronavirus spreads primarily through droplets from your mouth and nose, especially when you cough or sneeze. The C.D.C., one of the organizations using that measure, bases its recommendation of six feet on the idea that most large droplets that people expel when they cough or sneeze will fall to the ground within six feet. But six feet has never been a magic number that guarantees complete protection. Sneezes, for instance, can launch droplets a lot farther than six feet, according to a recent study. It’s a rule of thumb: You should be safest standing six feet apart outside, especially when it’s windy. But keep a mask on at all times, even when you think you’re far enough apart.
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I have antibodies. Am I now immune?
- As of right now, that seems likely, for at least several months. There have been frightening accounts of people suffering what seems to be a second bout of Covid-19. But experts say these patients may have a drawn-out course of infection, with the virus taking a slow toll weeks to months after initial exposure. People infected with the coronavirus typically produce immune molecules called antibodies, which are protective proteins made in response to an infection. These antibodies may last in the body only two to three months, which may seem worrisome, but that’s perfectly normal after an acute infection subsides, said Dr. Michael Mina, an immunologist at Harvard University. It may be possible to get the coronavirus again, but it’s highly unlikely that it would be possible in a short window of time from initial infection or make people sicker the second time.
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I’m a small-business owner. Can I get relief?
- The stimulus bills enacted in March offer help for the millions of American small businesses. Those eligible for aid are businesses and nonprofit organizations with fewer than 500 workers, including sole proprietorships, independent contractors and freelancers. Some larger companies in some industries are also eligible. The help being offered, which is being managed by the Small Business Administration, includes the Paycheck Protection Program and the Economic Injury Disaster Loan program. But lots of folks have not yet seen payouts. Even those who have received help are confused: The rules are draconian, and some are stuck sitting on money they don’t know how to use. Many small-business owners are getting less than they expected or not hearing anything at all.
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What are my rights if I am worried about going back to work?
“It seems backward to just ignore pre-symptomatic patients,” Dr. Butler-Wu said.
David Piegaro, who lives in Trenton, N.J., had sought out several tests for the coronavirus in recent months, after events like funerals and those that require travel because of his post in the national guard. He never experienced symptoms, and his tests have all been negative, bringing him peace of mind, especially because he lives with his parents and grandfather. “I viewed testing as a good thing to do,” he said. “Asymptomatic people could be spreading the virus, so widespread testing seems valuable.”
Tracking asymptomatic cases is also important from the perspective of the infected, Dr. Kuppalli said. Less than a year into this pandemic, experts still don’t know the full extent of the long-term consequences of contracting the coronavirus, even if the initial encounter seems benign.