(USA TODAY) -- Many workplaces have been working more feverishly than usual this flu season amid widespread infections that have left almost no state untouched.

The increased absences have forced healthy workers at smaller businesses to log extra hours.

"Fortunately, we don't really suffer any loss in productivity, and our customers don't really notice the difference," said Paul Pomeroy, director of marketing at Aloysius Butler & Clark, a Wilmington, Del., public relations firm. "Everyone has to work together to pick up the slack. It's part of doing business in a small business."

He said the pressure at his 61-employee workplace has stabilized in March as flu activity has declined.

During the second and third weeks of February, every state except Florida reported widespread flu activity. Only half as many states reported that level of flu infection in the same weeks last year, which was about when flu season peaked.

But for the week ended March 15, only 32 states reported widespread flu activity, according to the latest update from the Centers for Disease Control and Prevention.

CDC spokesman Curtis Allen said the flu vaccine failed to target a flu strain from Brisbane, Australia, that accounted for some of this season's flu infections.

Nikon's Melville, N.Y., location offered free flu shots to employees, which "didn't seem to help anybody this time around," said senior employee relations manager Doug Silverman. About 30 of the firm's 300 employees were absent daily between the middle of January and the end of February, he said.

Last month, a telecommunications company was forced to shut down its call center in Kansas for a day when roughly a third of its employees were out because of flu or stomach bug symptoms, said Roslyn Stone, chief operating officer of Corporate Wellness, a consulting firm that provides medical services to the company.

Corporate Wellness clients in the food services industry also struggled through Valentine's Day rushes with smaller workforces, she added.

"They were short-staffed," Stone said. "But they have no choice but to be hyper-sensitive about preventing people from working sick."

Keeping sick workers away is a priority for other employers, too.

A third of about 400 human resources professionals surveyed by the Society for Human Resource Management in January said they sent sick workers home to prevent the spread of the flu, while another 11% established policies allowing employees to work at home while sick.

Some employees wouldn't let themselves miss a day in the busy season, though.

Silverman said Nikon workers often battled illness at work because the company's national sales meetings and trade shows fell at the end of January and early February.

Sick employees often log onto the company server and work from home, he said.

"Fortunately, I don't think we missed a beat," Silverman said. "Those that were sick stayed on and fought through what they were experiencing."

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