A U.S. health economist is predicting slower economic growth in the third and fourth quarters of this year due to the impact of swine flu.

Bryce Sutton, an economist at the University of Alabama, says the H1N1 virus may cause individuals and business to cancel travel plans, hampering economic growth.

"Tourism and travel are vitally important sectors in the economy of many U.S. cities and communities," Sutton said in a release. "Depending on the severity of the spread of the virus, consumers and businesses may respond by restricting travel and vacation plans, which would dampen and already weak recovery in these areas."

He said industries that could take a hit include airlines, hotels and tour operators — businesses already suffering because of reduced consumer spending. Other businesses could also feel the impact of lowered employee productivity and increased absences.

Sutton pointed out that Sudden Acute Respiratory Syndrome, or SARS, in Asia led to a loss of between 0.5 per cent and two per cent of gross domestic product in the region.

What may offset such an impact are the extensive preparations by health officials for the next wave of H1N1, he said.