With more than a million deaths from the Covid-19 pandemic globally, the United States has overcome its own stage: 200,000 deaths caused by the new coronavirus. From the first known deaths in early February to the most recent deaths nearly eight months later, scientists and public health officials are gathering evidence on who killed the disease and why.
The data on death certificates collected by the Centers for Disease Control and Prevention show some consistent trends –more deaths among men than women (54% vs. 46% of the total), deaths that are highly distorted the adults, and minorities dies at a disproportionate rate. Studies also show people with major health problems, such as obesity and cardiovascular problems, are at higher risk.
The age data are clear: About 79% of reported deaths of Covid-1
This elderly population was severely affected in the spring, when significant outbreaks erupted in northeastern states such as New York, New Jersey and Massachusetts and spread through nursing homes. Deaths related to long-term care facilities recently reached 81,000 and consistently account for about 40% of all deaths in the United States Covid-19, according to the Wall Street Journal from state and federal data.
How deadly is Covid-19? How do scientists measure this?
To know how deadly Covid-19 is, scientists must first know how many people have been infected with the new coronavirus. Then they need a clear count of the number of deaths from the virus. Both numbers are still difficult to determine.
Colorful access to testing and in some areas a lack of testing have contributed to an underestimation of infections, public health researchers say. And many infected people never experience symptoms, making them less likely to seek a test. “We know we’ve missed so many infections”Said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota.
There are two widely listed ways to assess Covid-19 mortality: based only on known cases, often called percentage of fatalities, or based on a higher estimate of how many people probably had infections called infection mortality rate.
Using the latter method, research suggests a virus kills about 0.6% of the people it infects, but estimates vary considerably and the percentage varies considerably with age. This is far less than the death rate from other serious but less common coronavirus infections – SARS and MERS, also known as the Middle East Respiratory Syndrome – but about six times more deadly than seasonal flu.
Antibody tests have helped this study by revealing some previous infections, although tests are known for problems, including false positives. “It really just gives you a gestalt of what happened,” said David Brett-Major, a professor of epidemiology at the University of Nebraska College of Public Health.
Researchers at Johns Hopkins University, which tracks near-real-time case and death data, calculate mortality rate in the US is 2.9%, based on recent censuses of about 205,000 known deaths and 7,157,000 known cases that the university has registered on its widely listed Covid-19 dashboard. But these figures do not take into account all cases that have not been caught by testing.
Do improvements in Covid-19 treatment mean fewer people die from it?
The challenge of determining true mortality from Covid-19 does it is difficult to know for sure. Factors such as an increasing number of infections among young people and some improvements in treatment may have helped reduce mortality at least slightly, epidemiologists say.
Hospitals say they are getting better at managing patients with Covid-19. In March, when the pandemic intensified in the United States, about one in three of the sickest hospital patients died within 28 days of admission to the intensive care unit, and treatment varied widely, according to a study in 65 U.S. hospitals recently published in JAMA Internal Medicine. In March, doctors had limited research on Covid-19 treatment to guide their decisions, said David E. Leaf, a medical assistant at Harvard Medical School who worked on the study.
Today, doctors and hospitals can benefit from emerging research to the virus and lessons shared worldwide from early case care. Many warn that there is still limited good evidence as to which treatments work best.
Hospital treatment remains focused mainly on helping Covid-19 patients gain time for their immune system to fight SARS-CoV-2 infection. But doctors have gained some pharmaceutical options in recent months to help the seriously ill. One of the most promising achievements comes from studies that show that steroid drugs have helped reduce mortality from the virus. Another drug, the antiviral remdezivir, has been shown to help speed the recovery of hospitalized patients, but whether it can prevent death is unknown.
Studies continue to test other viable treatments which can prevent death or even prevent infections. Convalescent plasma may improve survival in some patients, studies show. Pharmaceutical companies are also testing certain engineered proteins called monoclonal antibodies that can temporarily prevent infection.
Selected drugs for treatment in development
- Steroids (dexamethasone, hydrocortisone) are aimed at an overactive immune system
- Antivirus tools (remdezivir, MK-4482) replication of target virus
- Monoclonal antibodies (REGN-COV-2, LY-CoV555, Actemra) targeted virus replication and overactive immune system
- AS inhibitors (Olumiant, Xeljanz) target an overactive immune system
Since age and basic health conditions are major risk factors, are young, healthy people safe from Covid-19?
Major medical conditions such as obesity, high blood pressure and diabetes, along with age, can increase the risk of serious illness for people who become infected with SARS-CoV-2 infections. “If you have Covid-19, your basic health is very important,” said Dr. Brett-Major.
However, young people are not completely risk-free. The The CDC has registered 419 Covid-19 deaths among people under the age of 25. And young people who are sick can put the more vulnerable at risk. Here’s what happened to outbreaks in countries like Texas and Florida this summer: Despite efforts to seal the most vulnerable, deaths and deaths have increased in nursing homes as wider communities have been affected.
“The reality is that cases are rising among young people, but we can’t keep the elderly isolated forever,” said Caroline Bucky, an associate professor of epidemiology at Harvard University’s University of Public Health TH Chan.
There is growing evidence of serious complications among survivors, even in people who have been only slightly ill or have been in good health before, including permanent heart damage, continued fatigue and other prolonged symptoms.
Meanwhile, while death certificates seem to make great sacrifices among people with major illnesses, they do tell an incomplete story when it comes to medical stories. Certificates are usually filled in by doctors who are not as well versed as trained death investigators on the causes of death and underlying conditions, said Dr. Sally Aiken, president of the National Association of Medical Experts.
Death certificate data show that about 94% of records of confirmed or suspected cases of Covid-19 indicate other conditions and causes, while 6% indicate only Covid-19 as a cause of death, according to the CDC. But some of the other conditions listed are diseases caused by Covid-19, such as pneumonia and respiratory failure.
The outbreaks have affected many college campuses. Does this change the proportion of people dying from Covid-19?
The risk of death from Covid-19 remains strongly associated with age, although deaths are slightly younger in some hotspots this summer. “Despite more cases among younger age groups, the severity of mortality is still in the elderly,” said Benjamin Lopman, an infectious disease epidemiologist at Emory University in Rollins School of Public Health.
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Although it takes many weeks to catch up with federal death certificate data, the trend in the known cases of Covid-19 is distorted younger this summer when the outbreaks passed through the states of the Sun. Deaths among people in their mid-20s to mid-50s account for a slightly higher proportion of total deaths in early summer than in spring, but the effects were barely noticeable as non-adult mortality was significantly lower, the researchers said.
“Paul Overberg and Joseph Walker contributed to this article.”
Write to John Camp at email@example.com and Melanie Evans at Melanie.Evans@wsj.com
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