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If You Have Coronavirus Symptoms, Assume You Have the Illness, Even if You Test Negative If You Have Coronavirus Symptoms, Assume You Have the Illness, Even if You Test Negative
(1 day later)
You had some exposures that may put you at risk for coronavirus. A few days later you come down with a bad cough yourself and feel a little short of breath and really tired. You take your temperature: 101 degrees. A fever.You had some exposures that may put you at risk for coronavirus. A few days later you come down with a bad cough yourself and feel a little short of breath and really tired. You take your temperature: 101 degrees. A fever.
You suspect you might have Covid-19, the disease caused by the novel coronavirus. The days roll into each other, and your doctor urges you to stay home unless your condition worsens. You feel pretty bad, though, and finally get an appointment.You suspect you might have Covid-19, the disease caused by the novel coronavirus. The days roll into each other, and your doctor urges you to stay home unless your condition worsens. You feel pretty bad, though, and finally get an appointment.
They test you for influenza by sticking a swab far up your nose, and you are told the test came back negative, you don’t have flu. They tell you they are saving the Covid-19 tests for those who are even worse off than you are. You go home with a prescription for antibiotics, possibly because they don’t know what else to do, and read about celebrities who are testing positive but don’t seem so sick.They test you for influenza by sticking a swab far up your nose, and you are told the test came back negative, you don’t have flu. They tell you they are saving the Covid-19 tests for those who are even worse off than you are. You go home with a prescription for antibiotics, possibly because they don’t know what else to do, and read about celebrities who are testing positive but don’t seem so sick.
A couple of days later, still with fevers, you go back, and the doctors relent and test you for SARS-CoV-2, the virus that causes Covid-19. They again stick something up your nose to what feels like the bottom of your eyeball.A couple of days later, still with fevers, you go back, and the doctors relent and test you for SARS-CoV-2, the virus that causes Covid-19. They again stick something up your nose to what feels like the bottom of your eyeball.
They tell you that the results will be available in a couple of days and you go home and wait. Finally, the results come back and you are told you do not have Covid-19. Now what?They tell you that the results will be available in a couple of days and you go home and wait. Finally, the results come back and you are told you do not have Covid-19. Now what?
This is a real patient’s story. In fact, it is a lot of people’s story — at least some version of it. Across the world, people with signs and symptoms of Covid-19 are testing negative and wondering what it means. They are not showing up in the statistics, and they are left in limbo about what to do next.This is a real patient’s story. In fact, it is a lot of people’s story — at least some version of it. Across the world, people with signs and symptoms of Covid-19 are testing negative and wondering what it means. They are not showing up in the statistics, and they are left in limbo about what to do next.
The problem may be with the test. Current coronavirus tests may have a particularly high rate of missing infections. The good news is that the tests appear to be highly specific: If your test comes back positive, it is almost certain you have the infection.The problem may be with the test. Current coronavirus tests may have a particularly high rate of missing infections. The good news is that the tests appear to be highly specific: If your test comes back positive, it is almost certain you have the infection.
The most common test to detect the coronavirus involves a process known as reverse transcription polymerase chain reaction, or RT-PCR, a jumble of words that describes a method capable of detecting virus particles that are generally present in respiratory secretions during the beginning of an infection. From a technical standpoint, under ideal conditions, these tests can detect small amounts of viral RNA.The most common test to detect the coronavirus involves a process known as reverse transcription polymerase chain reaction, or RT-PCR, a jumble of words that describes a method capable of detecting virus particles that are generally present in respiratory secretions during the beginning of an infection. From a technical standpoint, under ideal conditions, these tests can detect small amounts of viral RNA.
In the real world, though, the experience can be quite different, and the virus can be missed. The best the Centers for Disease Control and Prevention can say is that if you test negative, “you probably were not infected at the time your specimen was collected.” The key word there is “probably.”In the real world, though, the experience can be quite different, and the virus can be missed. The best the Centers for Disease Control and Prevention can say is that if you test negative, “you probably were not infected at the time your specimen was collected.” The key word there is “probably.”
False-negative test results — tests that indicate you are not infected, when you are — seem to be uncomfortably common. Increasingly, and disturbingly, I hear a growing number of anecdotal stories from my fellow doctors of patients testing negative for coronavirus and then testing positive — or people who are almost certainly infected who are testing negative.False-negative test results — tests that indicate you are not infected, when you are — seem to be uncomfortably common. Increasingly, and disturbingly, I hear a growing number of anecdotal stories from my fellow doctors of patients testing negative for coronavirus and then testing positive — or people who are almost certainly infected who are testing negative.
Updated June 30, 2020
Common symptoms include fever, a dry cough, fatigue and difficulty breathing or shortness of breath. Some of these symptoms overlap with those of the flu, making detection difficult, but runny noses and stuffy sinuses are less common. The C.D.C. has also added chills, muscle pain, sore throat, headache and a new loss of the sense of taste or smell as symptoms to look out for. Most people fall ill five to seven days after exposure, but symptoms may appear in as few as two days or as many as 14 days.
Scientists around the country have tried to identify everyday materials that do a good job of filtering microscopic particles. In recent tests, HEPA furnace filters scored high, as did vacuum cleaner bags, fabric similar to flannel pajamas and those of 600-count pillowcases. Other materials tested included layered coffee filters and scarves and bandannas. These scored lower, but still captured a small percentage of particles.
A commentary published this month on the website of the British Journal of Sports Medicine points out that covering your face during exercise “comes with issues of potential breathing restriction and discomfort” and requires “balancing benefits versus possible adverse events.” Masks do alter exercise, says Cedric X. Bryant, the president and chief science officer of the American Council on Exercise, a nonprofit organization that funds exercise research and certifies fitness professionals. “In my personal experience,” he says, “heart rates are higher at the same relative intensity when you wear a mask.” Some people also could experience lightheadedness during familiar workouts while masked, says Len Kravitz, a professor of exercise science at the University of New Mexico.
The steroid, dexamethasone, is the first treatment shown to reduce mortality in severely ill patients, according to scientists in Britain. The drug appears to reduce inflammation caused by the immune system, protecting the tissues. In the study, dexamethasone reduced deaths of patients on ventilators by one-third, and deaths of patients on oxygen by one-fifth.
The coronavirus emergency relief package gives many American workers paid leave if they need to take time off because of the virus. It gives qualified workers two weeks of paid sick leave if they are ill, quarantined or seeking diagnosis or preventive care for coronavirus, or if they are caring for sick family members. It gives 12 weeks of paid leave to people caring for children whose schools are closed or whose child care provider is unavailable because of the coronavirus. It is the first time the United States has had widespread federally mandated paid leave, and includes people who don’t typically get such benefits, like part-time and gig economy workers. But the measure excludes at least half of private-sector workers, including those at the country’s largest employers, and gives small employers significant leeway to deny leave.
So far, the evidence seems to show it does. A widely cited paper published in April suggests that people are most infectious about two days before the onset of coronavirus symptoms and estimated that 44 percent of new infections were a result of transmission from people who were not yet showing symptoms. Recently, a top expert at the World Health Organization stated that transmission of the coronavirus by people who did not have symptoms was “very rare,” but she later walked back that statement.
Touching contaminated objects and then infecting ourselves with the germs is not typically how the virus spreads. But it can happen. A number of studies of flu, rhinovirus, coronavirus and other microbes have shown that respiratory illnesses, including the new coronavirus, can spread by touching contaminated surfaces, particularly in places like day care centers, offices and hospitals. But a long chain of events has to happen for the disease to spread that way. The best way to protect yourself from coronavirus — whether it’s surface transmission or close human contact — is still social distancing, washing your hands, not touching your face and wearing masks.
A study by European scientists is the first to document a strong statistical link between genetic variations and Covid-19, the illness caused by the coronavirus. Having Type A blood was linked to a 50 percent increase in the likelihood that a patient would need to get oxygen or to go on a ventilator, according to the new study.
The unemployment rate fell to 13.3 percent in May, the Labor Department said on June 5, an unexpected improvement in the nation’s job market as hiring rebounded faster than economists expected. Economists had forecast the unemployment rate to increase to as much as 20 percent, after it hit 14.7 percent in April, which was the highest since the government began keeping official statistics after World War II. But the unemployment rate dipped instead, with employers adding 2.5 million jobs, after more than 20 million jobs were lost in April.
If air travel is unavoidable, there are some steps you can take to protect yourself. Most important: Wash your hands often, and stop touching your face. If possible, choose a window seat. A study from Emory University found that during flu season, the safest place to sit on a plane is by a window, as people sitting in window seats had less contact with potentially sick people. Disinfect hard surfaces. When you get to your seat and your hands are clean, use disinfecting wipes to clean the hard surfaces at your seat like the head and arm rest, the seatbelt buckle, the remote, screen, seat back pocket and the tray table. If the seat is hard and nonporous or leather or pleather, you can wipe that down, too. (Using wipes on upholstered seats could lead to a wet seat and spreading of germs rather than killing them.)
If you’ve been exposed to the coronavirus or think you have, and have a fever or symptoms like a cough or difficulty breathing, call a doctor. They should give you advice on whether you should be tested, how to get tested, and how to seek medical treatment without potentially infecting or exposing others.
Unfortunately, we have very little public data on the false-negative rate for these tests in clinical practice. Research coming out of China indicates that the false-negative rate may be around 30 percent. Some of my colleagues, experts in laboratory medicine, express concerns the false-negative rate in this country could be even higher.Unfortunately, we have very little public data on the false-negative rate for these tests in clinical practice. Research coming out of China indicates that the false-negative rate may be around 30 percent. Some of my colleagues, experts in laboratory medicine, express concerns the false-negative rate in this country could be even higher.
There are many reasons a test would be falsely negative under real-life conditions. Perhaps the sampling is inadequate. A common technique requires the collection of nasal secretions far back in the nose — and then rotating the swab several times. That is not an easy procedure to perform or for patients to tolerate. Other possible causes of false negative results are related to laboratory techniques and the substances used in the tests.There are many reasons a test would be falsely negative under real-life conditions. Perhaps the sampling is inadequate. A common technique requires the collection of nasal secretions far back in the nose — and then rotating the swab several times. That is not an easy procedure to perform or for patients to tolerate. Other possible causes of false negative results are related to laboratory techniques and the substances used in the tests.
So, where does that leave us? Even with more testing, we are likely to be underestimating the spread of the virus. For now, we should assume that anyone could be carrying the virus. If you have had likely exposures and symptoms suggest Covid-19 infection, you probably have it — even if your test is negative. We should all continue to practice the behaviors — rigorous hand washing, not touching the face, social distancing — that impede its spread. And we need better information about the performance of these tests — including any new tests that are introduced — in the real world.So, where does that leave us? Even with more testing, we are likely to be underestimating the spread of the virus. For now, we should assume that anyone could be carrying the virus. If you have had likely exposures and symptoms suggest Covid-19 infection, you probably have it — even if your test is negative. We should all continue to practice the behaviors — rigorous hand washing, not touching the face, social distancing — that impede its spread. And we need better information about the performance of these tests — including any new tests that are introduced — in the real world.
Even as better tests emerge, we should always put the test result in the context of the other information we have. It’s a lesson that endures throughout medicine: Look at the big picture, not a single piece of data. Triangulate on the truth, using all the sources of information you have, no matter how good a single test. And don’t be shy about questioning a conclusion that doesn’t fully fit the facts.Even as better tests emerge, we should always put the test result in the context of the other information we have. It’s a lesson that endures throughout medicine: Look at the big picture, not a single piece of data. Triangulate on the truth, using all the sources of information you have, no matter how good a single test. And don’t be shy about questioning a conclusion that doesn’t fully fit the facts.
Harlan Krumholz, M.D., is professor of medicine at Yale and director of the Yale New Haven Hospital Center for Outcomes Research and Evaluation.Harlan Krumholz, M.D., is professor of medicine at Yale and director of the Yale New Haven Hospital Center for Outcomes Research and Evaluation.