From air traffic controllers packed together in control towers to prisoners denied hand sanitizer for fear they might drink it, many U.S. government agencies would fall short if a dangerous pandemic struck, according to a report released to Congress on Tuesday.

Most agencies have planned to let employees work from home in case of a severe pandemic, but only one has actually tested this idea to see if it might work, the Government Accountability Office found.

The world is experiencing a pandemic of a new flu virus called H1N1 swine flu. The World Health Organization classifies it as a moderate pandemic, but says the virus could change at any time into a more dangerous form.

WHO says H1N1 has killed a confirmed 163 people and says there are likely to be many more deaths. Seasonal influenza is involved in 250,000 to 500,000 deaths annually.

"I think we really need to take a look at what we have learned from this current experience. We have a little bit of time — we are not in a drastic, severe situation," the GAO's Bernice Steinhardt, who led the study, said in a telephone interview.

Just before H1N1 emerged, Steinhardt's team surveyed 24 federal agencies to find out how well prepared they were for a worst-case scenario. She reported to the Senate Committee on Homeland Security and Governmental Affairs on Tuesday.

"Of the three pandemics of the 20th century, the most deadly was the influenza pandemic of 1918-1919 during which scientists estimate there were 50 million to 100 million deaths worldwide, including at least 675,000 in the United States, making it among the most deadly events in human history," the report reads.

"During the peak of an outbreak of a severe influenza pandemic in the United States, an estimated 40 percent of the workforce could be unable to work because of illness, the need to care for ill family members, or fear of infection."

WHO and U.S. health officials have been urging governments, companies and individuals to be ready for such a pandemic for years.

Steinhardt's assessment: "They are still muddling along."

UNTESTED PLANS

All 24 agencies had some sort of plan to allow flexible schedules and telework so people could avoid becoming infected while commuting or at the office, and could stay home with children if schools closed.

But few had tested the plans — and only 10 percent of federal employees who are eligible to telework right now do so, Steinhardt said.

The Bureau of Prisons reported it could not give hand sanitizer to prisoners because they might abuse it — it is alcohol based — and could not give masks and gloves to prisoners or guards because they might get knocked off in a riot — or could not be put on in time. Prisoners seeing guards in masks might become frightened, they said.

Air traffic controllers had virtually no options — they work in small control towers, cannot wear masks because their voices must be clear when they radio pilots, and they cannot even spray their shared work terminals with disinfectant for fear it will interfere with the electronics.

The controllers could not take antiviral drugs such as Roche AG's Tamiflu to protect themselves from infection because the Federal Aviation Administration has not tested whether it may affect their performance on the job.

"I don't know how they would handle it. I think they'd just have to cross their fingers," Steinhardt said.

She also recommends the federal government do more to coordinate with state and local officials about what they could and should do during a pandemic.