On October 6, 2020, the U.S. Centers for Disease Control and Prevention (CDC) once again revised its list of individuals whose risk factors make them more likely to develop severe illness from COVID-19.

First, the CDC expanded the list of underlying medical conditions and factors that may place adults of any age at “increased risk of severe illness” from COVID-19 to include the following:

• Cancer. The CDC stated that it is not currently known whether an individual with a history of cancer is at increased risk for severe illness.

• Smoking or a history of smoking. The CDC previously identified smoking only as potentially increasing a person’s risk for severe illness from COVID-19.

• Obesity. While obesity is not a new risk factor or category on the CDC’s “high-risk” list, the CDC has clarified that “obesity” (defined as a body mass index [BMI] of 30 kg/m² or higher but less than 40 kg/m²) or “severe obesity” (a BMI of 40 kg/m² or higher) “increases [the] risk of severe illness from COVID-19.” The CDC stated that individuals who are “overweight” (defined as a BMI of more than 25 kg/m² but less than 30 kg/m²) might be at increased risk of severe illness from COVID-19.

Second, the CDC revised its list regarding underlying medical conditions in children. The CDC removed from the “high-risk” list “neurologic, genetic, metabolic conditions or congenital heart disease in children (in addition to children with medical complexities).” According to the CDC, “[c]hildren with underlying medical conditions are at increased risk for severe illness compared to children without underlying medical conditions. Current evidence on which underlying medical conditions in children are associated with increased risk is limited.” Consequently, the CDC has refined its guidance to provide that “[c]hildren with the following conditions might be at increased risk for severe illness”:

• obesity;

• medical complexity;

• severe genetic disorders;

• severe neurologic disorders;

• inherited metabolic disorders;

• congenital (since birth) heart disease;

• diabetes;

• asthma and other chronic lung disease; and

• immunosuppression due to malignancy or immune-weakening medications.

The CDC also noted that it is not yet known which children are at increased risk for developing Multisystem Inflammatory Syndrome in Children (MIS-C), which the CDC described as a “rare but serious complication associated with COVID-19.”

In its October 16, 2020, Summary of Recent Changes, the CDC explained that the revisions regarding children “reflect[] the fact that there are less data available for children and [do] not imply that children are not at risk.” (Emphasis added.)

Outside of these changes, the CDC’s “high-risk” list and list of conditions that potentially increase a person’s risk for severe illness remain the same.