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They Were Infected With the Coronavirus. They Never Showed Signs. They Were Infected With the Coronavirus. They Never Showed Signs.
(31 minutes later)
In Anyang, China, five members of a family came down with the coronavirus after hosting a guest from Wuhan in early January. But the visitor, a 20-year-old woman, never got sick herself.In Anyang, China, five members of a family came down with the coronavirus after hosting a guest from Wuhan in early January. But the visitor, a 20-year-old woman, never got sick herself.
Some individuals who are infected with the coronavirus can spread it even though they have no symptoms, studies have shown.Some individuals who are infected with the coronavirus can spread it even though they have no symptoms, studies have shown.
Asymptomatic carriers are a well-known phenomenon. But the coronavirus is a new pathogen, and these cases may complicate scientific efforts to detect cases and to curb transmission.Asymptomatic carriers are a well-known phenomenon. But the coronavirus is a new pathogen, and these cases may complicate scientific efforts to detect cases and to curb transmission.
“I don’t think there’s any question that someone who is without symptoms and carrying the virus can transmit the virus to somebody else,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.“I don’t think there’s any question that someone who is without symptoms and carrying the virus can transmit the virus to somebody else,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.
“The question is, how prevalent is that phenomenon? Is that becoming an important driver of the outbreaks, or is it an unusual occurrence?”“The question is, how prevalent is that phenomenon? Is that becoming an important driver of the outbreaks, or is it an unusual occurrence?”
When asymptomatic carriers are important factors in an outbreak, he said, “you are going to put greater emphasis and burden on testing people.”When asymptomatic carriers are important factors in an outbreak, he said, “you are going to put greater emphasis and burden on testing people.”
At the moment, the Centers for Disease Control and Prevention allows for testing only symptomatic people who traveled to China recently or those who have had contact with someone who tested positive for coronavirus. (Officials have said the criteria may be re-evaluated.)At the moment, the Centers for Disease Control and Prevention allows for testing only symptomatic people who traveled to China recently or those who have had contact with someone who tested positive for coronavirus. (Officials have said the criteria may be re-evaluated.)
“We could be missing a great number of cases that don’t fit into those criteria,” said Dr. Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota.“We could be missing a great number of cases that don’t fit into those criteria,” said Dr. Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota.
“I suspect there are a number of additional cases in this country that are transmitting this virus, just like we’re seeing in other countries. Absence of evidence is not evidence of absence.”“I suspect there are a number of additional cases in this country that are transmitting this virus, just like we’re seeing in other countries. Absence of evidence is not evidence of absence.”
People who are infected but asymptomatic can spread disease efficiently. They are hardy and mobile. They have no reason to avoid crowds or kissing. They don’t know they are sick, and no one else does.People who are infected but asymptomatic can spread disease efficiently. They are hardy and mobile. They have no reason to avoid crowds or kissing. They don’t know they are sick, and no one else does.
These individuals are also hard to detect, suggesting that the current policies to try to contain the spread of the virus may not be adequate. Simply screening international travelers with symptoms of illness — and explicitly precluding tests of patients without a known link to China — may mean new cases are missed.These individuals are also hard to detect, suggesting that the current policies to try to contain the spread of the virus may not be adequate. Simply screening international travelers with symptoms of illness — and explicitly precluding tests of patients without a known link to China — may mean new cases are missed.
In February, Germany flew 126 people home from the Wuhan area. Ten passengers were segregated from the others, because they didn’t feel well or thought they had been exposed to the coronavirus. But everyone was offered testing.In February, Germany flew 126 people home from the Wuhan area. Ten passengers were segregated from the others, because they didn’t feel well or thought they had been exposed to the coronavirus. But everyone was offered testing.
The 10 isolated patients tested negative, but two people — who felt fine — surprised scientists by testing positive. They were hospitalized, monitored and tested repeatedly.The 10 isolated patients tested negative, but two people — who felt fine — surprised scientists by testing positive. They were hospitalized, monitored and tested repeatedly.
While one developed a mild rash and slightly sore throat, neither became ill.While one developed a mild rash and slightly sore throat, neither became ill.
There have been 59 confirmed coronavirus cases so far in the United States, but little testing has occurred for a country of this size. The C.D.C. has run only 445 tests, not counting tests on people who were repatriated.There have been 59 confirmed coronavirus cases so far in the United States, but little testing has occurred for a country of this size. The C.D.C. has run only 445 tests, not counting tests on people who were repatriated.
Most of the confirmed cases are passengers repatriated from the Diamond Princess cruise ship. The C.D.C. reported on Wednesday that two more passengers under quarantine have become ill.Most of the confirmed cases are passengers repatriated from the Diamond Princess cruise ship. The C.D.C. reported on Wednesday that two more passengers under quarantine have become ill.
Federal health officials warned on Tuesday that hospitals, schools and businesses needed to start preparing for outbreaks in the United States. Containment strategies may have to expand to include steps like closing schools, ordering people to work from home, and restricting public gatherings.Federal health officials warned on Tuesday that hospitals, schools and businesses needed to start preparing for outbreaks in the United States. Containment strategies may have to expand to include steps like closing schools, ordering people to work from home, and restricting public gatherings.
The secretary of health and human services, Alex M. Azar II, said he was alarmed by the infections occurring in some parts of the world that have no clear link to confirmed cases.The secretary of health and human services, Alex M. Azar II, said he was alarmed by the infections occurring in some parts of the world that have no clear link to confirmed cases.
Until now, the vast majority of infections and deaths have been in China, where the coronavirus originated in Wuhan before spreading to about 40 other nations.Until now, the vast majority of infections and deaths have been in China, where the coronavirus originated in Wuhan before spreading to about 40 other nations.
So far, at least 81,109 people have been infected and at least 2,718 have died.So far, at least 81,109 people have been infected and at least 2,718 have died.
But other countries may not have confirmed cases because they haven’t tested very many people or don’t have the resources to run tests.But other countries may not have confirmed cases because they haven’t tested very many people or don’t have the resources to run tests.
Some public health experts fear stealth transmissions may already be occurring in communities in the United States. But if sick individuals have no direct link to China, they will not be eligible for testing, so they will not be detected. That may help spread the disease.Some public health experts fear stealth transmissions may already be occurring in communities in the United States. But if sick individuals have no direct link to China, they will not be eligible for testing, so they will not be detected. That may help spread the disease.
Updated June 12, 2020Updated June 12, 2020
States are reopening bit by bit. This means that more public spaces are available for use and more and more businesses are being allowed to open again. The federal government is largely leaving the decision up to states, and some state leaders are leaving the decision up to local authorities. Even if you aren’t being told to stay at home, it’s still a good idea to limit trips outside and your interaction with other people. 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.
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.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.
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.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.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.
Mass protests against police brutality that have brought thousands of people onto the streets in cities across America are raising the specter of new coronavirus outbreaks, prompting political leaders, physicians and public health experts to warn that the crowds could cause a surge in cases. While many political leaders affirmed the right of protesters to express themselves, they urged the demonstrators to wear face masks and maintain social distancing, both to protect themselves and to prevent further community spread of the virus. Some infectious disease experts were reassured by the fact that the protests were held outdoors, saying the open air settings could mitigate the risk of transmission.Mass protests against police brutality that have brought thousands of people onto the streets in cities across America are raising the specter of new coronavirus outbreaks, prompting political leaders, physicians and public health experts to warn that the crowds could cause a surge in cases. While many political leaders affirmed the right of protesters to express themselves, they urged the demonstrators to wear face masks and maintain social distancing, both to protect themselves and to prevent further community spread of the virus. Some infectious disease experts were reassured by the fact that the protests were held outdoors, saying the open air settings could mitigate the risk of transmission.
Exercise researchers and physicians have some blunt advice for those of us aiming to return to regular exercise now: Start slowly and then rev up your workouts, also slowly. American adults tended to be about 12 percent less active after the stay-at-home mandates began in March than they were in January. But there are steps you can take to ease your way back into regular exercise safely. First, “start at no more than 50 percent of the exercise you were doing before Covid,” says Dr. Monica Rho, the chief of musculoskeletal medicine at the Shirley Ryan AbilityLab in Chicago. Thread in some preparatory squats, too, she advises. “When you haven’t been exercising, you lose muscle mass.” Expect some muscle twinges after these preliminary, post-lockdown sessions, especially a day or two later. But sudden or increasing pain during exercise is a clarion call to stop and return home.Exercise researchers and physicians have some blunt advice for those of us aiming to return to regular exercise now: Start slowly and then rev up your workouts, also slowly. American adults tended to be about 12 percent less active after the stay-at-home mandates began in March than they were in January. But there are steps you can take to ease your way back into regular exercise safely. First, “start at no more than 50 percent of the exercise you were doing before Covid,” says Dr. Monica Rho, the chief of musculoskeletal medicine at the Shirley Ryan AbilityLab in Chicago. Thread in some preparatory squats, too, she advises. “When you haven’t been exercising, you lose muscle mass.” Expect some muscle twinges after these preliminary, post-lockdown sessions, especially a day or two later. But sudden or increasing pain during exercise is a clarion call to stop and return home.
States are reopening bit by bit. This means that more public spaces are available for use and more and more businesses are being allowed to open again. The federal government is largely leaving the decision up to states, and some state leaders are leaving the decision up to local authorities. Even if you aren’t being told to stay at home, it’s still a good idea to limit trips outside and your interaction with other people.States are reopening bit by bit. This means that more public spaces are available for use and more and more businesses are being allowed to open again. The federal government is largely leaving the decision up to states, and some state leaders are leaving the decision up to local authorities. Even if you aren’t being told to stay at home, it’s still a good idea to limit trips outside and your interaction with other people.
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.
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.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 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.)
Taking one’s temperature to look for signs of fever is not as easy as it sounds, as “normal” temperature numbers can vary, but generally, keep an eye out for a temperature of 100.5 degrees Fahrenheit or higher. If you don’t have a thermometer (they can be pricey these days), there are other ways to figure out if you have a fever, or are at risk of Covid-19 complications.Taking one’s temperature to look for signs of fever is not as easy as it sounds, as “normal” temperature numbers can vary, but generally, keep an eye out for a temperature of 100.5 degrees Fahrenheit or higher. If you don’t have a thermometer (they can be pricey these days), there are other ways to figure out if you have a fever, or are at risk of Covid-19 complications.
The C.D.C. has recommended that all Americans wear cloth masks if they go out in public. This is a shift in federal guidance reflecting new concerns that the coronavirus is being spread by infected people who have no symptoms. Until now, the C.D.C., like the W.H.O., has advised that ordinary people don’t need to wear masks unless they are sick and coughing. Part of the reason was to preserve medical-grade masks for health care workers who desperately need them at a time when they are in continuously short supply. Masks don’t replace hand washing and social distancing.The C.D.C. has recommended that all Americans wear cloth masks if they go out in public. This is a shift in federal guidance reflecting new concerns that the coronavirus is being spread by infected people who have no symptoms. Until now, the C.D.C., like the W.H.O., has advised that ordinary people don’t need to wear masks unless they are sick and coughing. Part of the reason was to preserve medical-grade masks for health care workers who desperately need them at a time when they are in continuously short supply. Masks don’t replace hand washing and social distancing.
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.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.
If you’re sick and you think you’ve been exposed to the new coronavirus, the C.D.C. recommends that you call your healthcare provider and explain your symptoms and fears. They will decide if you need to be tested. Keep in mind that there’s a chance — because of a lack of testing kits or because you’re asymptomatic, for instance — you won’t be able to get tested.If you’re sick and you think you’ve been exposed to the new coronavirus, the C.D.C. recommends that you call your healthcare provider and explain your symptoms and fears. They will decide if you need to be tested. Keep in mind that there’s a chance — because of a lack of testing kits or because you’re asymptomatic, for instance — you won’t be able to get tested.
“To our knowledge there is no sustained transmission in this country at this point unless it is under the radar,” Dr. Fauci said.“To our knowledge there is no sustained transmission in this country at this point unless it is under the radar,” Dr. Fauci said.
In Italy, health officials in some regions have taken a different approach.In Italy, health officials in some regions have taken a different approach.
After 10 deaths attributed to the new coronavirus, health officials started aggressive and widespread testing in some regions. They turned up hundreds of other infections, including many in people who did not display any symptoms.After 10 deaths attributed to the new coronavirus, health officials started aggressive and widespread testing in some regions. They turned up hundreds of other infections, including many in people who did not display any symptoms.
Quarantines have been imposed on at least 10 towns, and the movement of tens of thousands of people has been limited. There have been no deaths attributed to the coronavirus in the United States.Quarantines have been imposed on at least 10 towns, and the movement of tens of thousands of people has been limited. There have been no deaths attributed to the coronavirus in the United States.
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Earlier reports about asymptomatic transmission — including a published report about a Chinese woman who visited Germany for a few days in January, infecting several colleagues there and not realizing she was ill until she returned home — have been criticized.Earlier reports about asymptomatic transmission — including a published report about a Chinese woman who visited Germany for a few days in January, infecting several colleagues there and not realizing she was ill until she returned home — have been criticized.
A follow-up report said the woman had vague symptoms, like fatigue, though not the kind of symptoms typically associated with the coronavirus.A follow-up report said the woman had vague symptoms, like fatigue, though not the kind of symptoms typically associated with the coronavirus.
If it is true that asymptomatic or minimally symptomatic people can transmit the disease frequently and efficiently, testing may need to be broadened, experts said.If it is true that asymptomatic or minimally symptomatic people can transmit the disease frequently and efficiently, testing may need to be broadened, experts said.
“This implies we may need many more tests that can be used out in the field, at the point of care,” said Dr. Judith N. Wasserheit, co-director of the University of Washington MetaCenter for Pandemic Preparedness and Global Health Security. “We’re still learning about the biology of this virus and how it causes disease.”“This implies we may need many more tests that can be used out in the field, at the point of care,” said Dr. Judith N. Wasserheit, co-director of the University of Washington MetaCenter for Pandemic Preparedness and Global Health Security. “We’re still learning about the biology of this virus and how it causes disease.”
Dr. Sandra Ciesek, of the Institute of Medical Virology at University Hospital Frankfurt, who was one of the authors of a letter in The New England Journal of Medicine that described the German patients who did not become ill, said the problem was that “normally, you don’t screen asymptomatic healthy people for the virus because it’s too expensive.”Dr. Sandra Ciesek, of the Institute of Medical Virology at University Hospital Frankfurt, who was one of the authors of a letter in The New England Journal of Medicine that described the German patients who did not become ill, said the problem was that “normally, you don’t screen asymptomatic healthy people for the virus because it’s too expensive.”
“This shows we might have more infected people already all over the world than we expect,” she said.“This shows we might have more infected people already all over the world than we expect,” she said.