Named an unexpected factor in severe COVID-19 progression

Former childhood cancer patients found to be at increased risk for COVID-19 - shocking discovery by Swedish scientists

Scientists focused on more than 13,000 people who were diagnosed with cancer before the age of 20. By the start of the pandemic, all of them had already reached adulthood. For the purity of the experiment, researchers compared them with their siblings, as well as with a random sample of peers.

The results were paradoxical: former cancer patients were less likely to contract COVID-19, but if the disease did catch up with them, the risk of severe course increased by a whole 58%. Severe course meant hospitalization, intensive care, or death.

"It's important to understand that despite the lower infection rate, the consequences of the disease for this group were much more serious," emphasized Javier Louro, lead author of the study and postdoc at the Institute of Environmental Medicine at Karolinska Institute.

This pattern was especially pronounced during peak incidence periods - during waves caused by the Alpha and Omicron strains. Interestingly, in Sweden, where anti-COVID measures were predominantly advisory in nature, the risk of severe disease for former cancer patients was higher than in neighboring Denmark with its strict restrictions.

"Our results indicate that people who had cancer in childhood should be considered a vulnerable group in future pandemics and other health crises. This may include priority vaccination or special protective measures during periods of high incidence," Louro concluded.