Orlando, Florida - Exxon plans to keep some refinery workers living in the plants to keep them going. A small Southern grocery chain is thinking about drive-through pickup of soup and bread.

The U.S. Labor Department's Occupational Safety and Health Administration urged employers to develop plans to cope with a possible flu pandemic on Tuesday, suggesting letting employees work from home and encouraging sick workers to stay home without reprisals.

But a few international companies and small regional firms were already making bird flu planning a full-time job, and said on Tuesday they have had to prepare for the unthinkable.

Jay Schwartz, vice president of information systems at North Carolina-based Alex Lee Inc., is worried about what will happen when food supplies begin to get scarce as people become ill, stay home to care for children when schools close or tend to ill relatives.

"Security is a huge issue," Schwartz, whose company owns a chain of grocery stores and an institutional food supplier, told a conference in Orlando.

Big food trucks may be targeted by bandits. "Maybe we'll have someone riding shotgun for added security," Schwartz told the Business Preparedness for Pandemic Influenza summit, sponsored by the Center for Infectious Disease Research and Policy at the University of Minnesota.

Experts almost universally agree that the world is ripe for a pandemic of some infectious disease. The H5N1 avian influenza virus is considered the leading candidate to cause one.

It can sometimes infect people and has sickened at least 271, killing 166 of them, according to the latest World Health Organization count.

If the virus mutated in just the right way, it could easily begin spreading like common respiratory infections -- only with much more deadly effect. WHO predicts the outcome would be devastating.

"During a pandemic, workplaces can likely experience high absenteeism -- probably as much as 40 percent of the workforce," OSHA official Amanda Edens told reporters.

Learning by Trial and Error

"What we are trying to find are the few who have those critical first-step plans that are going to help others," said Mike Osterholm, a University of Minnesota infectious disease expert who arranged the conference.

One big concern -- how to keep employees on the job if schools close and people begin to fear big gatherings. In a pandemic, the biggest danger may be the person next to you.

"We don't have the option of shutting facilities down. We have the obligation of providing energy," said James McEnery, deputy vice-president for human resources at Exxon Mobil Corp.

"We are going to ask some employees to come in and live in the facility," McEnery told the conference.

Food suppliers also feel an obligation, Schwartz said.

His stores may switch to products that people can stock, such as canned stew. They may arrange for drive-through pickup to avoid person-to-person contact. But this presents its own problems.

"What do you do if a guy pulls up in a pickup truck and wants to buy all the soup?" Schwartz asked.

Other companies feel well set up to make use of teleworkers.

"Everybody has got a laptop," said James Wall, global managing director of human resources for Deloitte Touche Tohmatsu. "Our plans assume that people would have to shelter in place and stay where they are."

Some companies plan to offer moral support, too.

"We employ approximately 200 chaplains of many faiths," said Ken Kimbro, a vice president at Tyson Foods Inc. "We rely very heavily upon this group in times of stress."