Resea8k8 com register onlinerch shows one person in five at risk of severe COVID-19 infection

Around 1.7 billion people across the globe are at risk of developing severe cases of COVID-19 if infected with the novel coronavirus, according to a new study.

Researchers at the London School of Hygiene and Tropical Medicine, or LSHTM, estimate that 22 percent of the global population－or around one in five people－have at least one existing underlying health condition that makes them at risk of severe COVID-19 if infected.

The study estimates that in 350 million people, or 4.5 percent of the world population, infection would be so bad it would require hospitalization.

These findings, published in medical journal The Lancet, can be used to assess the number of high-risk people that would be prioritized for vaccines when they become available, according to lead author Andrew Clark, an associate professor at the LSHTM.

"As countries move out of lockdown, governments are looking for ways to protect the most vulnerable from a virus that is still circulating," said Clark. "We hope our estimates will provide useful starting points for designing measures to protect those at increased risk of severe disease. This might involve advising people with underlying conditions to adopt social distancing measures appropriate to their level of risk, or prioritizing them for vaccination in the future."

Clark and his team analyzed disease and demographic data from 188 nations to reach their findings. The researchers paid particular attention to rates of diseases identified by the World Health Organization and other public health bodies as risk factors for severe COVID-19 infection. These include cardiovascular disease, chronic kidney disease, diabetes and chronic respiratory disease.

Places with younger populations have fewer people with at least one underlying health condition, the study said, while those with older populations have more.

For example, the proportion of the population with one or more health condition ranges from 16 percent in Africa to 31 percent in Europe. But this should not be a cause for complacency in Africa, Clark warned.

"The share of the population at increased risk of severe COVID-19 is generally lower in Africa than elsewhere due to much younger country populations, but a much higher proportion of severe cases could be fatal in Africa than elsewhere," he explained.

In Africa, countries with a high prevalence of HIV, such as Botswana and Lesotho, have a greater proportion of people with an underlying condition than countries with lower prevalence, such as Niger.

Small island nations with high rates of diabetes, such as Fiji and Mauritius, had a high proportion of people with increased risk.

Age was another determining factor behind the severity of COVID-19 infection in populations studied.

Worldwide, less than 5 percent of people aged under 20 have at least one underlying condition that could increase their risk of severe COVID-19, whereas 66 percent of those aged 70 and above do have such a condition.

"Our estimates suggest that age-based thresholds for shielding could play a role in reducing deaths and reducing the number of people who require hospital treatment," said Rosalind Eggo, an assistant professor at LSHTM.