WASHINGTON (Reuters) - The U.S. Department of Homeland Security (DHS), which protects sites ranging from land borders and airports to the White House, may not be able to maintain operations in a pandemic due to inadequate supplies of protective gear and drugs for its staff, according to a government report on Thursday.

An audit, conducted by the DHS Office of Inspector General (OIG) and posted on a congressional website, said the sprawling bureaucracy has bought more than $16 million of gear and anti-viral drugs since 2006, often without determining how much it needed or keeping track of where supplies were stored.

The report was released ahead of a House of Representatives committee hearing, scheduled for Friday, to examine the Obama administration’s response to the Ebola outbreak that has killed at least 4,877 people, mainly in West Africa, and infected two Texas healthcare workers since arriving on U.S. soil last month.

The OIG report, which was completed in August, has no direct bearing on the government response to Ebola, a virus that public health officials say poses no major health threat to the United States. But it underscores the need for adequate preparedness at a time of elevated public anxiety about deadly contagion.

“The department may not be able to provide pandemic preparedness supplies that are adequate to continue operations during a pandemic,” DHS Inspector General John Roth said in written testimony submitted along with the audit report to the House Committee on Oversight and Government Reform, the panel conducting Friday’s hearing.

“DHS did not really know how much protective equipment it had on hand or where the equipment was being stored,” he added.

“The department’s entire respirator stockpile has reached, or soon will reach, the manufacturer’s date of guaranteed usability.”

About one-quarter million courses of antiviral drugs were purchased before the department determined its need for the medication. More than 30,000 are now being recalled for safety or efficacy concerns, while hundreds more were reported destroyed but remained intact, according to the auditors.

DHS purchased the protective stockpiles to protect its own staff to maintain the operations of agencies including the Secret Service, the Federal Emergency Management Agency, U.S. Customs and Border Protection and Immigration and Customs Enforcement.