Experts calculate odds of infection and death rates for coronavirus

SINGAPORE — Left unchecked, the coronavirus that causes COVID19 could infect billions of people. By one estimate, up to 70% of the world’s population may contract the disease.

That means there’s an excellent chance that, sooner or later, you will be one of them.

The World Health Organization said 14% of people known to have COVID-19 develop symptoms severe enough to require hospitalization and oxygen support. But calculating the odds of survival in the early stages of the pandemic is imprecise.

The disease’s fatality rate, which compares the number of people with confirmed cases of COVID-19 to the number of people who have died from it, has fluctuated between 0.9% and 3.4% depending on the latest available data. None of them are truly accurate, however, since health officials have no idea how many people have been infected but weren’t sick enough to warrant medical attention and be counted.

“The full burden of disease is not understood until there is time to breathe and analyze the data,” said Gene Olinger, an immunologist with the Marylandbased scientific institute MRIGlobal.

Researchers will need to account for factors like climate, access to health care and genetics to build a full picture of COVID-19, including who is most vulnerable. (Tuberculosis, for example, kills about 1.5 million people each year, but its incidence varies greatly depending on climate and geography.)

Despite the current uncertainty, early research seems to show a persistent pattern about which group is most vulnerable: Older adults, particularly those with underlying medical conditions, are at much greater risk of dying from the coronavirus than younger, healthier people.

After inspecting conditions in China last month, an expert panel assembled by the World Health Organization reported that patients with underlying health problems died at substantially higher rates.

Among patients of all ages without preexisting medical conditions, the fatality rate was 1.4%, the panel found. That compares with 13.2% for those with cardiovascular disease, 9.2% for those with diabetes, 8.4% for people with hypertension, 8% for patients with chronic respiratory disease and 7.6% for those with cancer.

Meanwhile, patients aged 80 and over died at a rate of 21.9%.

Another study examining 201 patients in a hospital in Wuhan, China, concluded that patients 60 and older were more likely to succumb to fatal respiratory symptoms triggered by COVID-19 because their immune systems were weaker.

A separate study published last month by researchers at the Chinese Center for Disease Control and Prevention examined nearly 45,000 confirmed cases of COVID-19 in China and found that while the overall fatality rate was 2.3%, it jumped to 8% for patients in their 70s and soared to 14.8% for patients 80 and older.