HEBER CITY, Utah — Harry R. Weyandt worries about a deadly flu pandemic reaching the United States for a different reason from most people: It would overwhelm his business.

Nice on the bottom line. Murder on the nerves.

There's no pandemic yet, and bird flu hasn't shown up in North America. But the staff at Weyandt's disaster preparedness store is already scrambling to keep up with demand for everything from freeze-dried foods to first-aid kits.

"What I'm not looking forward to is when they announce the first bird with avian flu is in the country," said Weyandt, owner of Nitro-Pak Preparedness Center Inc. in Heber City, about 35 miles southeast of Salt Lake City. "Because I know what will happen. It'll be crazy here."

Sales of emergency supplies are booming amid growing fears of a virulent global flu. Across the country, suppliers say they're already struggling to keep stock on hand, and it's taking longer to fill orders.

Phyllis Hopkins of Best Prices Storable Foods in Quinlan, Texas, said the business barely had a breather between the Gulf Coast hurricanes last year and bird flu warnings that intensified over the winter.

"We can't keep product in stock," said Hopkins, who runs the business with her husband, Bruce Hopkins. "As soon as it comes in, it goes right off the shelf."

Pandemic panic buying means heady times for such businesses, which are typically family-owned and have no more than a handful of employees.

Weyandt said Nitro-Pak's March sales this year were up 600 percent from last year. He wouldn't reveal the company's finances, but said total sales last year were in the "mid-seven figures."

Nitro-Pak's storefront warehouse looks like a cross between a Costco for survivalists and the post office before the Christmas holiday rush. Cardboard crates stacked floor-to-ceiling spill over with long-burning emergency candles, mini-rolls of toilet paper, waterproof matches and freeze-dried foods ranging from eggs with bacon to blueberry cheesecake.

Scurrying between boxes, workers race to fill orders and load them onto heavy pallets that ship out every afternoon.

Even Weyandt's office, a sparsely furnished affair not much bigger than a typical master bedroom, has desks overflowing with backpacks, compasses and space blankets.

A strain of bird flu known as H5N1 has killed millions of chickens and more than 100 people worldwide since 2003, mostly in Asia. While the deaths are blamed on close contact with sick poultry, experts are afraid the virus could mutate to spread easily among people.

If it arrives in North America, even businesses that stand to make a fortune say they're not prepared.

"This industry is so teeny that if something happens to get everybody in a panic, it can't handle it," said Richard Man-kamyer, owner of The Survival Center in McKenna, Wash.