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How Long Will Coronavirus Live on Surfaces or in the Air Around You? How Long Will Coronavirus Live on Surfaces or in the Air Around You?
(2 months later)
The coronavirus can live for three days on some surfaces, like plastic and steel, new research suggests. Experts say the risk of consumers getting infected from touching those materials is still low, although they offered additional warnings about how long the virus survives in air, which may have important implications for medical workers.The coronavirus can live for three days on some surfaces, like plastic and steel, new research suggests. Experts say the risk of consumers getting infected from touching those materials is still low, although they offered additional warnings about how long the virus survives in air, which may have important implications for medical workers.
The new study, published Tuesday in The New England Journal of Medicine, also suggests that the virus disintegrates over the course of a day on cardboard, lessening the worry among consumers that deliveries will spread the virus during this period of staying and working from home.The new study, published Tuesday in The New England Journal of Medicine, also suggests that the virus disintegrates over the course of a day on cardboard, lessening the worry among consumers that deliveries will spread the virus during this period of staying and working from home.
When the virus becomes suspended in droplets smaller than five micrometers — known as aerosols — it can stay suspended for about a half-hour, researchers said, before drifting down and settling on surfaces where it can linger for hours. (In the study’s experimental setup, the virus stayed suspended for three hours, but it would drift down much sooner under most conditions.) The finding on aerosol in particular is inconsistent with the World Health Organization’s position that the virus is not transported by air.When the virus becomes suspended in droplets smaller than five micrometers — known as aerosols — it can stay suspended for about a half-hour, researchers said, before drifting down and settling on surfaces where it can linger for hours. (In the study’s experimental setup, the virus stayed suspended for three hours, but it would drift down much sooner under most conditions.) The finding on aerosol in particular is inconsistent with the World Health Organization’s position that the virus is not transported by air.
The virus lives longest on plastic and steel, surviving for up to 72 hours. But the amount of viable virus decreases sharply over this time. It also does poorly on copper, surviving four hours. On cardboard, it survives up to 24 hours, which suggests packages that arrive in the mail should have only low levels of the virus — unless the delivery person has coughed or sneezed on it or has handled it with contaminated hands.The virus lives longest on plastic and steel, surviving for up to 72 hours. But the amount of viable virus decreases sharply over this time. It also does poorly on copper, surviving four hours. On cardboard, it survives up to 24 hours, which suggests packages that arrive in the mail should have only low levels of the virus — unless the delivery person has coughed or sneezed on it or has handled it with contaminated hands.
That’s true in general. Unless the people who handle any of these materials are sick, the actual risk of getting infected from any of these materials is low, experts said.That’s true in general. Unless the people who handle any of these materials are sick, the actual risk of getting infected from any of these materials is low, experts said.
“Everything at the grocery store and restaurant takeout containers and bags could in theory have infectious virus on them,” said Dr. Linsey Marr, who was not a member of the research team but is an expert in the transmission of viruses by aerosol at Virginia Tech in Blacksburg. “We could go crazy discussing these ‘what ifs’ because everyone is a potential source, so we have to focus on the biggest risks.”“Everything at the grocery store and restaurant takeout containers and bags could in theory have infectious virus on them,” said Dr. Linsey Marr, who was not a member of the research team but is an expert in the transmission of viruses by aerosol at Virginia Tech in Blacksburg. “We could go crazy discussing these ‘what ifs’ because everyone is a potential source, so we have to focus on the biggest risks.”
If people are concerned about the risk, they could wipe down packages with disinfectant wipes and wash their hands, she said.If people are concerned about the risk, they could wipe down packages with disinfectant wipes and wash their hands, she said.
It is unclear why cardboard should be a less hospitable environment for the virus than plastic or steel, but it may be explained by the absorbency or fibrous quality of the packaging compared with the other surfaces.It is unclear why cardboard should be a less hospitable environment for the virus than plastic or steel, but it may be explained by the absorbency or fibrous quality of the packaging compared with the other surfaces.
That the virus can survive and stay infectious in aerosols is also important for health care workers.That the virus can survive and stay infectious in aerosols is also important for health care workers.
For weeks experts have maintained that the virus is not airborne. But in fact, it can travel through the air and stay suspended for that period of about a half-hour.For weeks experts have maintained that the virus is not airborne. But in fact, it can travel through the air and stay suspended for that period of about a half-hour.
The virus does not linger in the air at high enough levels to be a risk to most people who are not physically near an infected person. But the procedures health care workers use to care for infected patients are likely to generate aerosols.The virus does not linger in the air at high enough levels to be a risk to most people who are not physically near an infected person. But the procedures health care workers use to care for infected patients are likely to generate aerosols.
“Once you get a patient in with severe pneumonia, the patients need to be intubated,” said Dr. Vincent Munster, a virologist at the National Institute of Allergy and Infectious Diseases who led the study. “All these handlings might generate aerosols and droplets.”“Once you get a patient in with severe pneumonia, the patients need to be intubated,” said Dr. Vincent Munster, a virologist at the National Institute of Allergy and Infectious Diseases who led the study. “All these handlings might generate aerosols and droplets.”
Health care workers might also collect those tiny droplets and larger ones on their protective gear when working with infected patients. They might resuspend these big and small droplets into the air when they take off this protective gear and become exposed to the virus then, Dr. Marr cautioned.Health care workers might also collect those tiny droplets and larger ones on their protective gear when working with infected patients. They might resuspend these big and small droplets into the air when they take off this protective gear and become exposed to the virus then, Dr. Marr cautioned.
A study that is being reviewed by experts bears out this fear. And another study, published March 4 in JAMA, also indicates that the virus is transported by air. That study, based in Singapore, found the virus on a vent in the hospital room of an infected patient, where it could only have reached via the air.A study that is being reviewed by experts bears out this fear. And another study, published March 4 in JAMA, also indicates that the virus is transported by air. That study, based in Singapore, found the virus on a vent in the hospital room of an infected patient, where it could only have reached via the air.
Dr. Marr said the World Health Organization had so far referred to the virus as not airborne, but that health care workers should wear gear, including respirator masks, assuming that it is.Dr. Marr said the World Health Organization had so far referred to the virus as not airborne, but that health care workers should wear gear, including respirator masks, assuming that it is.
“Based on aerosol science and recent findings on flu virus,” she said, “surgical masks are probably insufficient.”“Based on aerosol science and recent findings on flu virus,” she said, “surgical masks are probably insufficient.”
Dr. Marr said based on physics, an aerosol released at a height of about six feet would fall to the ground after 34 minutes. The findings should not cause the general public to panic, however, because the virus disperses quickly in the air.Dr. Marr said based on physics, an aerosol released at a height of about six feet would fall to the ground after 34 minutes. The findings should not cause the general public to panic, however, because the virus disperses quickly in the air.
“It sounds scary,” she said, “but unless you’re close to someone, the amount you’ve been exposed to is very low.”“It sounds scary,” she said, “but unless you’re close to someone, the amount you’ve been exposed to is very low.”
Dr. Marr compared this to cigarette smoke or a foggy breath on a frosty day. The closer and sooner another person is to the exhaled smoke or breath, the more of a whiff they might catch; for anyone farther than a few feet away, there is too little of the virus in the air to be any danger.Dr. Marr compared this to cigarette smoke or a foggy breath on a frosty day. The closer and sooner another person is to the exhaled smoke or breath, the more of a whiff they might catch; for anyone farther than a few feet away, there is too little of the virus in the air to be any danger.
Updated June 2, 2020
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.
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.
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.)
More than 40 million people — the equivalent of 1 in 4 U.S. workers — have filed for unemployment benefits since the pandemic took hold. One in five who were working in February reported losing a job or being furloughed in March or the beginning of April, data from a Federal Reserve survey released on May 14 showed, and that pain was highly concentrated among low earners. Fully 39 percent of former workers living in a household earning $40,000 or less lost work, compared with 13 percent in those making more than $100,000, a Fed official said.
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.
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.
To assess the ability of the virus to survive in the air, the researchers created what Dr. Munster described as “bizarre experiments done under very ideal controllable experimental conditions.” They used a rotating drum to suspend the aerosols, and provided temperature and humidity levels that closely mimic hospital conditions.To assess the ability of the virus to survive in the air, the researchers created what Dr. Munster described as “bizarre experiments done under very ideal controllable experimental conditions.” They used a rotating drum to suspend the aerosols, and provided temperature and humidity levels that closely mimic hospital conditions.
In this setup, the virus survived and stayed infectious for up to three hours, but its ability to infect drops sharply over this time, he said.In this setup, the virus survived and stayed infectious for up to three hours, but its ability to infect drops sharply over this time, he said.
He said the aerosols might stay aloft only for about 10 minutes, but Dr. Marr disagreed with that assessment, and said they could stay in the air for three times longer. She also said that the experimental setup might be less comfortable for the virus than a real-life setting.He said the aerosols might stay aloft only for about 10 minutes, but Dr. Marr disagreed with that assessment, and said they could stay in the air for three times longer. She also said that the experimental setup might be less comfortable for the virus than a real-life setting.
For example, she said, the researchers used a relative humidity of 65 percent. “Many, but not all viruses, have shown that they survive worst at this level of humidity,” she said. They do best at lower or much higher humidity. The humidity in a heated house is less than 40 percent, “at which the virus might survive even longer,” she said.For example, she said, the researchers used a relative humidity of 65 percent. “Many, but not all viruses, have shown that they survive worst at this level of humidity,” she said. They do best at lower or much higher humidity. The humidity in a heated house is less than 40 percent, “at which the virus might survive even longer,” she said.
Mucus and respiratory fluids might also allow the virus to survive longer than the laboratory fluids the researchers used for their experiments.Mucus and respiratory fluids might also allow the virus to survive longer than the laboratory fluids the researchers used for their experiments.
Other experts said the paper’s findings illustrate the urgent need for more information about the virus’s ability to survive in aerosols, and under different conditions.Other experts said the paper’s findings illustrate the urgent need for more information about the virus’s ability to survive in aerosols, and under different conditions.
“We need more experiments like this, in particular, extending the experimental sampling time for aerosolized virus beyond three hours and testing survival under different temperature and humidity conditions,” said Dr. Jeffrey Shaman, an environmental health sciences expert at Columbia University.“We need more experiments like this, in particular, extending the experimental sampling time for aerosolized virus beyond three hours and testing survival under different temperature and humidity conditions,” said Dr. Jeffrey Shaman, an environmental health sciences expert at Columbia University.
Dr. Munster noted that, over all, the new coronavirus seems no more capable of surviving for long periods than its close cousins SARS and MERS, which caused previous epidemics. That suggests there are other reasons, such as transmission by people who don’t have symptoms, for its ability to cause a pandemic.Dr. Munster noted that, over all, the new coronavirus seems no more capable of surviving for long periods than its close cousins SARS and MERS, which caused previous epidemics. That suggests there are other reasons, such as transmission by people who don’t have symptoms, for its ability to cause a pandemic.