Also reinstated are an estimated 150 employees at the CDC’s National Center for Environmental Health, including people staffing a lab that works on lead poisoning, according to the union and employees. Layoffs at federal agencies were challenged in lawsuits, with judges in some cases ordering federal agencies to halt terminations of employees.

More than 460 laid-off employees at the nation's top public health agency received notices on Wednesday that they are being reinstated, according to a union representing the workers.

As part of a Trump administration plan to eliminate 10,000 health and human services positions, about 2,400 CDC employees lost their jobs in a wave of cuts across several federal health agencies. Entire programs were shut down — some focused on lead poisoning,