(Reuters) – Global deaths from COVID-19 have reached 1 million, but experts are still struggling to find a critical metric in epidemics: mortality – the percentage of people who die from a pathogen infection.
Here’s a look at the issues to better understand COVID-19 mortality.
How is the mortality rate calculated?
The true mortality rate will compare the total number of deaths compared to the number of infections, a cult that is unknown because it is difficult to measure the full scope of asymptomatic cases. Many people who become infected do not experience symptoms.
Scientists say the total number of infections is growing faster than the number of currently confirmed cases, which now stands at 33 million globally. Many experts believe that the coronavirus potentially kills 0.5% to 1% of people, making it a very dangerous virus globally until the vaccine is identified.
Researchers have begun to break down that risk by age group, as evidence mounts that young people and children are much less likely to develop serious disease.
The mortality rate for people under the age of 20 is probably one in 10,000. Dr. Christopher Murray, director of the Institute of Health Metrics and Evaluation at Seattle and Washington Washington University, said that at age 85, he was around one in six.
What is a “case death rate”?
Mortality is significantly reduced when measured against the number of new infections confirmed by coronavirus testing. In places like the United States, that “case death rate” dropped dramatically from 6.6% in April to just 3% in August Gust, according to Reuters.
But experts say there has been a significant reduction in the number of people with mild illness or no symptoms by more comprehensive testing than in the early days of the epidemic. It is also credited with improving the treatment of serious illness and rescuing some of the most at-risk groups.
“We are more aware of potential difficulties and how to identify and treat them,” said Dr. Mash Adalja of the Johns Hopkins University Center for Health Security in Baltimore. “If you’re a patient who gets covid-19 in 2020, you’ll get it now than in March.”
What does this mean for individuals and governments?
It highlights the need for constant vigilance, as some countries are beginning to experience a second wave of infection.
For example, French researchers estimate that the country’s case mortality rate has dropped by a percentage point by the end of July compared to the end of May, which is due to increased testing, improved medical care, and higher rates of infection in young people. Serious illness is less likely.
“We are now seeing a new increase in hospital admissions and ICU (intensive care unit) enrollment, which means this discrepancy is about to end,” said Mircia Sophona, a researcher at the University of Montpellier in France. “We have to understand why.”
Reporting by Dina Beasley; Additional report by Matthias Blymont in Paris; Edited by Will Dunham