Underlying health risks that could worsen an infection

ONE in five people across the world has an underlying health condition that could increase their risk of severe coronavirus if infected, a new study suggests.

Using data from 188 countries, a modelling study estimated that 1.7 billion people – 22% of the world population – have at least one underlying health condition that puts them at increased risk.

Researchers say that although estimates give an indication of the number of people who should be prioritised for protective measures, not all of these individuals would go on to develop severe symptoms if infected.

According to the study, 4% of the world’s population would require hospitalisation if infected.

The authors say this suggests the increased risk of severe Covid-19 could be quite modest for many with underlying conditions.

Associate Professor Andrew Clark, from the London School of Hygiene and Tropical Medicine (LSHTM), said: “As countries move out of lockdown, governments are looking for ways to protect the most vulnerable from a virus that is still circulating.

“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 prioritising them for vaccination in the future.”

The World Health Organisation (WHO) and public health agencies in the UK and USA identify cardiovascular disease, chronic kidney disease, diabetes and chronic respiratory disease as risk factors for severe coronavirus.

The new study, in The Lancet Global Health journal, provides global, regional and national estimates for the number of people with underlying health conditions.

The authors caution that they focused on underlying chronic conditions and did not include other possible risk factors that are not yet included in all guidelines, such as ethnicity and socioeconomic deprivation.

They say that the estimates are therefore unlikely to be exhaustive, but serve as a starting point for policymakers.