'Why We Don’t Know the True Death Rate for Covid-19' diff viewer (10/11)

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Why We Don’t Know the True Death Rate for Covid-19	Why We Don’t Know the True Death Rate for Covid-19
2020-06-17 03:06:43 UTC	2020-06-17 16:21:00 UTC (about 13 hours later)
Coroners in some parts of the country are overwhelmed. Funeral homes in coronavirus hot spots can barely keep up. Newspaper obituary pages in hard-hit areas go on and on. Covid-19 is on track to kill far more people in the United States this year than the seasonal flu.	Coroners in some parts of the country are overwhelmed. Funeral homes in coronavirus hot spots can barely keep up. Newspaper obituary pages in hard-hit areas go on and on. Covid-19 is on track to kill far more people in the United States this year than the seasonal flu.
But determining just how deadly the new coronavirus will be is a key question facing epidemiologists, who expect resurgent waves of infection that could last into 2022.	But determining just how deadly the new coronavirus will be is a key question facing epidemiologists, who expect resurgent waves of infection that could last into 2022.
As the virus spread across the world in late February and March, the projection circulated by infectious disease experts of how many infected people would die seemed plenty dire: around 1 percent, or 10 times the rate of a typical flu.	As the virus spread across the world in late February and March, the projection circulated by infectious disease experts of how many infected people would die seemed plenty dire: around 1 percent, or 10 times the rate of a typical flu.
But according to various unofficial Covid-19 trackers that calculate the death rate by dividing total deaths by the number of known cases, about 6.4 percent of people infected with the virus have now died worldwide.	But according to various unofficial Covid-19 trackers that calculate the death rate by dividing total deaths by the number of known cases, about 6.4 percent of people infected with the virus have now died worldwide.
In Italy, the death rate stands at about 13 percent, and in the United States, around 4.3 percent, according to the latest figures on known cases and deaths. Even in South Korea, where widespread testing helped contain the outbreak, 2 percent of people who tested positive for the virus have died, recent data shows.	In Italy, the death rate stands at about 13 percent, and in the United States, around 4.3 percent, according to the latest figures on known cases and deaths. Even in South Korea, where widespread testing helped contain the outbreak, 2 percent of people who tested positive for the virus have died, recent data shows.
These supposed death rates also appear to vary widely by geography: Germany’s fatality rate appears to be roughly one-tenth of Italy’s, and Los Angeles’s about half of New York’s. Among U.S. states, Michigan, at around 7 percent, is at the high end, while Wyoming, which reported its first two deaths this week, has one of the lowest death rates, at about 0.7 percent.	These supposed death rates also appear to vary widely by geography: Germany’s fatality rate appears to be roughly one-tenth of Italy’s, and Los Angeles’s about half of New York’s. Among U.S. states, Michigan, at around 7 percent, is at the high end, while Wyoming, which reported its first two deaths this week, has one of the lowest death rates, at about 0.7 percent.
Virology experts say there is no evidence that any strain of the virus, officially known as SARS-CoV-2, has mutated to become more severe in some parts of the world than others, raising the question of why there appears to be so much variance from country to country.	Virology experts say there is no evidence that any strain of the virus, officially known as SARS-CoV-2, has mutated to become more severe in some parts of the world than others, raising the question of why there appears to be so much variance from country to country.
Determining death rates is especially challenging in the midst of a pandemic, while figures are necessarily fluid. Fatality rates based on comparing deaths, which are relatively easy to count, to infections, which are not, almost certainly overestimate the true lethality of the virus, epidemiologists say. Health officials and epidemiologists have estimated there are five to 10 people with undetected infections for every confirmed case in some communities, and at least one estimate suggests there are far more.	Determining death rates is especially challenging in the midst of a pandemic, while figures are necessarily fluid. Fatality rates based on comparing deaths, which are relatively easy to count, to infections, which are not, almost certainly overestimate the true lethality of the virus, epidemiologists say. Health officials and epidemiologists have estimated there are five to 10 people with undetected infections for every confirmed case in some communities, and at least one estimate suggests there are far more.
On top of that, deaths lag infections. The thousands of people with Covid-19 who died this week in the United States were most likely infected as far back as a month ago. So as the number of new cases reported begins to fall in hard-hit places like New York City, the death rate will almost certainly rise.	On top of that, deaths lag infections. The thousands of people with Covid-19 who died this week in the United States were most likely infected as far back as a month ago. So as the number of new cases reported begins to fall in hard-hit places like New York City, the death rate will almost certainly rise.
“To know the fatality rate you need to know how many people are infected and how many people died from the disease,” said Ali H. Mokdad, a professor of health metrics sciences at the Institute for Health Metrics and Evaluation. “We know how many people are dying, but we don’t know how many people are infected.”	“To know the fatality rate you need to know how many people are infected and how many people died from the disease,” said Ali H. Mokdad, a professor of health metrics sciences at the Institute for Health Metrics and Evaluation. “We know how many people are dying, but we don’t know how many people are infected.”
In fact, even the number of people dying is a moving target. Covid-19 deaths that happen at home appear to be widely underreported. And New York City increased its death count by more than 3,700 on Tuesday, after officials said they were now including people who had never tested positive for the virus but were presumed to have died of it.	In fact, even the number of people dying is a moving target. Covid-19 deaths that happen at home appear to be widely underreported. And New York City increased its death count by more than 3,700 on Tuesday, after officials said they were now including people who had never tested positive for the virus but were presumed to have died of it.
But the missing data on deaths in the deaths-to-infections ratio is still almost certain to be dwarfed by the expected increase in the denominator when the total number of infections is better understood, epidemiologists say. The statistic typically cited by mayors and governors at Covid-19 news conferences relies on a data set that includes mostly people whose symptoms were severe enough to be tested.	But the missing data on deaths in the deaths-to-infections ratio is still almost certain to be dwarfed by the expected increase in the denominator when the total number of infections is better understood, epidemiologists say. The statistic typically cited by mayors and governors at Covid-19 news conferences relies on a data set that includes mostly people whose symptoms were severe enough to be tested.
Epidemiologists call it “severity bias.” It is why the fatality rate in Wuhan, China, where the outbreak began, was reported to be between 2 percent and 3.4 percent before it was revised to 1.4 percent, and it may yet be lower.	Epidemiologists call it “severity bias.” It is why the fatality rate in Wuhan, China, where the outbreak began, was reported to be between 2 percent and 3.4 percent before it was revised to 1.4 percent, and it may yet be lower.
One intriguing case study for epidemiologists looking for the true fatality rate is the Diamond Princess cruise ship, which became a kind of natural experiment when nearly all of its 3,711 passengers and crew members were tested for the coronavirus after an outbreak on board.	One intriguing case study for epidemiologists looking for the true fatality rate is the Diamond Princess cruise ship, which became a kind of natural experiment when nearly all of its 3,711 passengers and crew members were tested for the coronavirus after an outbreak on board.
The ship’s “case fatality rate,” which included only those who showed symptoms, was 2.6 percent, according to a study by researchers at the London School of Hygiene and Tropical Medicine, while the “infection fatality rate,” which included those who tested positive yet remained asymptomatic, was 1.3 percent. (A cruise ship, in which people are in a confined space, is not representative of the more dynamic situation in cities). The known number of coronavirus cases worldwide is about two million, and at least 127,000 of those patients have died. The United States has an estimated 600,000 reported cases and more than 25,000 deaths, the most in the world. But many people infected with the virus have no symptoms, or only mild ones, and appear in no official tally.	The ship’s “case fatality rate,” which included only those who showed symptoms, was 2.6 percent, according to a study by researchers at the London School of Hygiene and Tropical Medicine, while the “infection fatality rate,” which included those who tested positive yet remained asymptomatic, was 1.3 percent. (A cruise ship, in which people are in a confined space, is not representative of the more dynamic situation in cities). The known number of coronavirus cases worldwide is about two million, and at least 127,000 of those patients have died. The United States has an estimated 600,000 reported cases and more than 25,000 deaths, the most in the world. But many people infected with the virus have no symptoms, or only mild ones, and appear in no official tally.
Facing a shortage of tests to confirm who has the disease and who does not, and fearing a shortage of I.C.U. beds, hospitals in some areas of the United States have declined to test or admit people whose oxygen saturation is above 90 percent.	Facing a shortage of tests to confirm who has the disease and who does not, and fearing a shortage of I.C.U. beds, hospitals in some areas of the United States have declined to test or admit people whose oxygen saturation is above 90 percent.
Whether a particular locale tests people with even mild symptoms is a key factor in determining how many people were infected, but testing capacity has been limited in many places.	Whether a particular locale tests people with even mild symptoms is a key factor in determining how many people were infected, but testing capacity has been limited in many places.
“People with mild symptoms, I just send them home,” said Amesh Adalja, a senior scholar at Johns Hopkins Center for Health Security, and a critical care physician in Pittsburgh. “All of this is creating disparities in case-fatality ratios that don’t reflect real differences.”	“People with mild symptoms, I just send them home,” said Amesh Adalja, a senior scholar at Johns Hopkins Center for Health Security, and a critical care physician in Pittsburgh. “All of this is creating disparities in case-fatality ratios that don’t reflect real differences.”
Even with testing now becoming more widely available for Americans with Covid-19 symptoms, the proportion of people infected by the virus who do not feel appreciably sick is unknown, including in places with some of the highest deaths per 100,000 people: New York (55), Spain (40), Belgium (36), Italy (35), New Jersey (32), France (23) and Louisiana (22).	Even with testing now becoming more widely available for Americans with Covid-19 symptoms, the proportion of people infected by the virus who do not feel appreciably sick is unknown, including in places with some of the highest deaths per 100,000 people: New York (55), Spain (40), Belgium (36), Italy (35), New Jersey (32), France (23) and Louisiana (22).
A clue comes from Iceland, which has tested 6 percent of its population, perhaps the highest proportion of any country. Of those who tested positive, 43 percent had no symptoms at the time, though it is likely that many developed them later.	A clue comes from Iceland, which has tested 6 percent of its population, perhaps the highest proportion of any country. Of those who tested positive, 43 percent had no symptoms at the time, though it is likely that many developed them later.
What scientists call the infection fatality rate is so closely watched because even a seemingly trivial decrease — from, say, 1.0 percent to 0.9 percent — could mean a few hundred thousand fewer deaths in a population the size of the United States. It is also used to calibrate interventions aimed at preventing more deaths with their grim economic consequences.	What scientists call the infection fatality rate is so closely watched because even a seemingly trivial decrease — from, say, 1.0 percent to 0.9 percent — could mean a few hundred thousand fewer deaths in a population the size of the United States. It is also used to calibrate interventions aimed at preventing more deaths with their grim economic consequences.
Over the coming months, tests that can identify antibodies in the blood of people who were unwittingly exposed to the virus will allow for a closer approximation of total infections in different populations.	Over the coming months, tests that can identify antibodies in the blood of people who were unwittingly exposed to the virus will allow for a closer approximation of total infections in different populations.
Both the Centers for Disease Control and Prevention and the National Institutes of Health recently announced that they would begin using antibody tests to see what proportion of the U.S. population has already been infected. Covid-19 may prove to be less lethal than initial predictions, with an infection fatality rate of under 1 percent, as suggested in an editorial published in the New England Journal of Medicine by Dr. Anthony S. Fauci and Dr. H. Clifford Lane, both of the National Institute of Allergy and Infectious Diseases, and Dr. Robert R. Redfield, director of the C.D.C.	Both the Centers for Disease Control and Prevention and the National Institutes of Health recently announced that they would begin using antibody tests to see what proportion of the U.S. population has already been infected. Covid-19 may prove to be less lethal than initial predictions, with an infection fatality rate of under 1 percent, as suggested in an editorial published in the New England Journal of Medicine by Dr. Anthony S. Fauci and Dr. H. Clifford Lane, both of the National Institute of Allergy and Infectious Diseases, and Dr. Robert R. Redfield, director of the C.D.C.
Updated June 16, 2020	Updated June 16, 2020
	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.	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.	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.	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.	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.
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.
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.