The Health and Human Services' Office of Inspector General is launching an audit into how the Food and Drug Administration responded leading up to the massive February recall of baby formula and closure of Abbott Nutrition's Sturgis plant.
OIG's review, first reported by ABC News, will examine whether the FDA upheld its duty "to safeguard the nation's food supply, including infant formula and ensure all ingredients are safe" and if FDA regulators followed proper recall protocol once a deadly bacteria had been detected inside the plant.
The Sturgis, Michigan, plant was shut down in mid-February after contamination issues inside had been linked to four infants being hospitalized with a rare but serious bacterial infection, two of whom ultimately died.
The review of the FDA's actions marks an extraordinary and uncommon move from the watchdog agency.
Its advent also punctuates loud, frustrated calls from the American public and lawmakers alike for accountability on the ongoing infant formula shortage - a now-national supply crisis which was exacerbated by Abbott's contamination issues and ultimate shutdown.
This is not first time Abbott's quality control has come under questioning.
Federal regulators warned months ago of potential problems at a manufacturing plant for baby formula, according to documents and a public timeline of the events.
The FDA found sanitation issues at Abbott's Sturgis plant in September 2021, saying it "did not maintain a building used in the manufacture, processing, packing or holding of infant formula in a clean and sanitary condition," according to an inspection report.
By Feb. 1, FDA had collected samples at the plant confirming the presence of cronobacter, according to an inspection report. Abbott maintains there is no conclusive evidence that its products contributed to the death of two infants.
But it wasn't until mid-February when Abbott, the largest infant formula manufacturer in the country, issued a voluntary recall.
The drastic move quickly slashed a significant share of the U.S. formula supply - a market that had already begun to show signs of strain from pandemic supply chain disruptions.
There is also a 34-page whistleblower report from a former employee of Abbott Laboratories, which alleges a "litany of violations" and contamination issues at Abbott's Sturgis facility.
But that complaint remained in limbo for months after it was sent to the FDA in October 2021. Agency leaders recently testified before members of Congress that they didn't receive that report last fall "due to an isolated failure in FDA's mailroom, likely due to COVID-19 staffing issues."
The complaint was not seen by top officials until mid-February, FDA's deputy commissioner for food policy and response, Frank Yiannas said, roughly four months after it had landed at the agency.
As families still desperately scramble to find the food they need for their children, serious questions loom large about whether a breakdown in the chain of command and communication at the agency abetted a sluggish response to the growing problem. Some are asking whether more could have been done by the government to address sanitation issues and operational issues - and possibly prevent a nationwide shortage.
ABC News has reached out to the FDA for comment on the new IG review.
Findings from OIG's review are expected sometime in fiscal year 2024.
ABC News' Anne Flaherty and Kaitlyn Folmer contributed to this report.