To the Editor:

The disability rate of the American civilian labor force (ACLF) is a proxy for the nation’s burden of disease. Monitoring the value of this statistic is a matter of statistical process control, and should be a priority for public health officials. An alarming recent significant increase in the disability rate, which shows no sign of abating as of 2025 Q2, demands an explanation, given its concurrence with the rollout of the COVID vaccines late in 2020 and throughout 2021.