"HHS is conducting an ongoing, comprehensive internal investigation in response to the whistleblower’s claims," an HHS spokesperson said in an email to ABC News. "HHS is also conducting an ongoing, comprehensive investigation into what protocols and procedures were followed at both facilities."
The HHS spokesperson also noted that "no (Administration for Children and Families) ACF employees involved with repatriating persons from China were exposed to any individuals who tested positive for the virus."
"Furthermore, the 14-day window for the virus to manifest itself has long since passed and no ACF employee has become ill with COVID-19," the spokesperson said.
"Therefore, testing for the virus is not medically necessary. Nonetheless, to allay any employee anxiety, HHS will administer tests to deployed ACF employees who request it."
ABC News has not reviewed the complaint, and lawyers representing the whistleblower have refused to provide it. However, Ari Wilkenfeld, one of the whistleblower's attorneys, told ABC News that an article by The Washington Post accurately describes the allegations laid out in the complaint.
The Oversight Subcommittee of Ways and Means reviewed the complaint and told ABC News that there’s too much identifying information in it to release it publicly, and the committee is working to protect the identity of the whistleblower.
"The whistleblower alleges that staff were sent into quarantined areas ‘without personal protective equipment, training, or experience in managing public health emergencies, safety protocols, and the potential danger to both themselves and members of the public they came into contact with," the letter to Azar said.
The HHS spokesperson said HHS will brief Congress and the public once it completes the investigation.
"At this time, it would be premature to provide further details about the substance of the complaint, nor can HHS discuss personnel matters publicly," the HHS spokesperson said.
ABC News’ John Parkinson and Katherine Faulders contributed to this report.