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They Recovered From the Coronavirus. Were They Infected Again? They Recovered From the Coronavirus. Were They Infected Again?
(8 days later)
Can people who recover from a bout with the new coronavirus become infected again — and again?Can people who recover from a bout with the new coronavirus become infected again — and again?
The Japanese government reported this week that a woman in Osaka had tested positive for the coronavirus for a second time, weeks after recovering from the infection and being discharged from a hospital.The Japanese government reported this week that a woman in Osaka had tested positive for the coronavirus for a second time, weeks after recovering from the infection and being discharged from a hospital.
Combined with reports from China of similar cases, the case in Japan has raised some uncomfortable questions. Reinfections are common among people who have recovered from coronaviruses that cause the common cold.Combined with reports from China of similar cases, the case in Japan has raised some uncomfortable questions. Reinfections are common among people who have recovered from coronaviruses that cause the common cold.
But those pathogens are very different from the new coronavirus, and experts said it’s unlikely that these are cases of people getting infected a second time.But those pathogens are very different from the new coronavirus, and experts said it’s unlikely that these are cases of people getting infected a second time.
“I’m not saying that reinfection can’t occur, will never occur, but in that short time it’s unlikely,” said Florian Krammer, a virologist at the Icahn School of Medicine at Mount Sinai in New York.“I’m not saying that reinfection can’t occur, will never occur, but in that short time it’s unlikely,” said Florian Krammer, a virologist at the Icahn School of Medicine at Mount Sinai in New York.
Even the mildest of infections should leave at least short-term immunity against the virus in the recovering patient, he said.Even the mildest of infections should leave at least short-term immunity against the virus in the recovering patient, he said.
More likely, the “reinfected” patients still harbored low levels of the virus when they were discharged from the hospital, and testing failed to pick it up.More likely, the “reinfected” patients still harbored low levels of the virus when they were discharged from the hospital, and testing failed to pick it up.
Even if there were occasional cases of reinfection, they do not seem to be occurring in numbers large enough to be a priority at this point in the outbreak.Even if there were occasional cases of reinfection, they do not seem to be occurring in numbers large enough to be a priority at this point in the outbreak.
A report published Thursday in JAMA supports the idea that people may test positive for the virus long after they seem to have recovered.A report published Thursday in JAMA supports the idea that people may test positive for the virus long after they seem to have recovered.
In four medical professionals exposed to the virus in Wuhan, China, the epicenter of the epidemic, a test that detects the viral genetic material remained positive five to 13 days after they were asymptomatic.In four medical professionals exposed to the virus in Wuhan, China, the epicenter of the epidemic, a test that detects the viral genetic material remained positive five to 13 days after they were asymptomatic.
This does not necessarily mean that they were still able to infect others, however.This does not necessarily mean that they were still able to infect others, however.
The PCR diagnostic test is highly sensitive and can amplify genetic material from even a single viral molecule. As such, the test could merely be picking up fragments of the virus.The PCR diagnostic test is highly sensitive and can amplify genetic material from even a single viral molecule. As such, the test could merely be picking up fragments of the virus.
PCR tests may detect remnants of the measles virus months after people who had the disease stop shedding infectious virus, Dr. Krammer said.PCR tests may detect remnants of the measles virus months after people who had the disease stop shedding infectious virus, Dr. Krammer said.
The other possibility is that the negative test was done poorly, or the samples were stored at a temperature at which the virus deteriorates. The throat swab may also simply miss the virus that is hiding elsewhere in the body.The other possibility is that the negative test was done poorly, or the samples were stored at a temperature at which the virus deteriorates. The throat swab may also simply miss the virus that is hiding elsewhere in the body.
“A virus test is positive if the virus was there on the swab in sufficient quantities at the time you swabbed the person,” said Marc Lipsitch, an epidemiologist at the Harvard T.H. Chan School of Public Health.“A virus test is positive if the virus was there on the swab in sufficient quantities at the time you swabbed the person,” said Marc Lipsitch, an epidemiologist at the Harvard T.H. Chan School of Public Health.
“A negative test is not a definitive that there is no more virus in that person.”“A negative test is not a definitive that there is no more virus in that person.”
Dr. Lipsitch offered an analogy: a jam jar with mold on top. Scraping off the surface might give the impression that the jam is now mold-free, but in fact the jar may still contain mold that continues to grow.Dr. Lipsitch offered an analogy: a jam jar with mold on top. Scraping off the surface might give the impression that the jam is now mold-free, but in fact the jar may still contain mold that continues to grow.
The Japanese woman initially had mild symptoms of coronavirus infection and tested positive in late January. She was released from the hospital on Feb. 1. She tested positive again on Wednesday after coming in for a sore throat and chest pain.The Japanese woman initially had mild symptoms of coronavirus infection and tested positive in late January. She was released from the hospital on Feb. 1. She tested positive again on Wednesday after coming in for a sore throat and chest pain.
“That certainly sounds like it could be an actual resurgence of the virus in infectious form,” Dr. Lipsitch said. But, he added, “Single anecdotes are really hard to interpret.”“That certainly sounds like it could be an actual resurgence of the virus in infectious form,” Dr. Lipsitch said. But, he added, “Single anecdotes are really hard to interpret.”
One worrisome possibility is that the coronavirus follows what is known as a biphasic infection: the virus persists and causes a different set of symptoms than observed in the initial bout.One worrisome possibility is that the coronavirus follows what is known as a biphasic infection: the virus persists and causes a different set of symptoms than observed in the initial bout.
Updated June 24, 2020
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.
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.
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.
In patients infected with Ebola, the virus may persist for months in the testes or eyes even after recovery — and can infect others and keep the epidemic going.In patients infected with Ebola, the virus may persist for months in the testes or eyes even after recovery — and can infect others and keep the epidemic going.
The recovered person, too, can develop other symptoms, including insomnia and neurological problems, said Angela Rasmussen, a virologist at Columbia University.The recovered person, too, can develop other symptoms, including insomnia and neurological problems, said Angela Rasmussen, a virologist at Columbia University.
“We don’t know if that’s the case with this coronavirus,” Dr. Rasmussen said. “We don’t know anything about this virus.”“We don’t know if that’s the case with this coronavirus,” Dr. Rasmussen said. “We don’t know anything about this virus.”
Coronaviruses are on the whole poorly understood, she said. Before the SARS epidemic, coronaviruses were not known to cause serious illnesses.Coronaviruses are on the whole poorly understood, she said. Before the SARS epidemic, coronaviruses were not known to cause serious illnesses.
Some scientists have said that people infected with the new coronavirus produce antibodies that will protect them in the future. And a single-patient report suggests that the immunity may last at least seven days.Some scientists have said that people infected with the new coronavirus produce antibodies that will protect them in the future. And a single-patient report suggests that the immunity may last at least seven days.
But this finding is neither surprising nor reassuring, said Dr. Stanley Perlman, a coronavirus expert at the University of Iowa. “The issue is whether you’ll see it in seven months or in a year,” he said. “That’s what you care about.”But this finding is neither surprising nor reassuring, said Dr. Stanley Perlman, a coronavirus expert at the University of Iowa. “The issue is whether you’ll see it in seven months or in a year,” he said. “That’s what you care about.”
The new coronavirus closely resembles the ones that cause SARS and, to a lesser extent, MERS. There are no reports of reinfections with the SARS virus, Dr. Perlman said, and only one that he has heard of in a patient recovering from MERS.The new coronavirus closely resembles the ones that cause SARS and, to a lesser extent, MERS. There are no reports of reinfections with the SARS virus, Dr. Perlman said, and only one that he has heard of in a patient recovering from MERS.
Dr. Perlman’s research with MERS has shown that the strength of the immune response depends on the severity of the infection, but that even in those with severe disease — which should produce the strongest immune responses — the immunity seemed to wane within a year.Dr. Perlman’s research with MERS has shown that the strength of the immune response depends on the severity of the infection, but that even in those with severe disease — which should produce the strongest immune responses — the immunity seemed to wane within a year.
How long immunity lasts will also be a key question to resolve when designing a vaccine for the new coronavirus, particularly if the virus becomes a seasonal threat like influenza.How long immunity lasts will also be a key question to resolve when designing a vaccine for the new coronavirus, particularly if the virus becomes a seasonal threat like influenza.
“What is the nature of immunity to this virus after infection?” Dr. Lipsitch said. “That’s a research question that’s urgent.”“What is the nature of immunity to this virus after infection?” Dr. Lipsitch said. “That’s a research question that’s urgent.”