Childhood Cancer Survivors More Prone to Severe COVID-19

Adults who had cancer during childhood are significantly more likely to suffer serious complications from COVID-19. Although medical advances have led to increasing survival rates among children with cancer, long-term health challenges can persist well into adulthood. A recent registry-based analysis highlights that these individuals remain vulnerable long after completing their cancer treatment. The investigation focused on how childhood cancer survivors in Sweden and Denmark were affected during the COVID-19 pandemic.

Comparison with Siblings and General Population

The study analyzed data from more than 13,000 individuals diagnosed with cancer before age 20, all of whom were at least 20 years old when the pandemic started. These individuals were compared with their siblings and with randomly selected individuals from the general population, matched by gender and year of birth.

Interestingly, childhood cancer survivors were at a lower risk of contracting COVID-19. However, once infected, they were 58 percent more likely to develop severe illness, which included hospitalization, admission to intensive care, or death related to the virus.

Severity of Illness During High Transmission Periods

“It is important to understand that even though these individuals were not infected more often, the consequences were more serious when they did become ill,” explained Javier Louro, a postdoctoral researcher at the Institute of Environmental Medicine at Karolinska Institutet and lead author of the publication.

The risk became even more pronounced during phases of high viral transmission—especially when more infectious variants such as Alpha and Omicron spread rapidly. Differences in national responses also played a role, with Swedish survivors showing a greater risk increase compared to their Danish counterparts.

Public Health Implications for Future Pandemics

Sweden's approach, based more on public recommendations than strict restrictions, may have contributed to the higher impact seen there, in contrast to Denmark's early and firm preventive actions.

Louro emphasized that childhood cancer survivors should be prioritized for vaccination and special protection measures in future pandemics or other public health emergencies.

Published in The Lancet Regional Health – Europe, this analysis shows the ongoing health vulnerability faced by those who survived cancer as children. Despite their lower likelihood of infection, the risk of serious illness upon contracting COVID-19 remains significantly higher prompting a call for targeted health protections for this group in times of crisis.

Reference:

1. COVID-19 infection and severity among childhood cancer survivors in Denmark and Sweden: a register-based cohort study with matched population and sibling comparisons - (https://www.thelancet.com/journals/lanepe/article/PIIS2666-7762(25)00155-3/fulltext)

Source-Medindia