In the past decade of tracking viruses, for the first time, Rapid City Regional Hospital has seen all four major viruses peak at the same time in the past few weeks, James Keegan, vice president of clinical quality, said.

"It's really hit the community hard quickly and significantly," Keegan said Thursday. The announcement was the first of what will be ongoing weekly reports about viruses in the community.

Those four major viruses are Influenza A and B, parainfluenza and respiratory syncytial virus, commonly called RSV.

"Those viruses are very dangerous for babies, very dangerous for the elderly and people with compromised immune systems," he said.

Keegan said the pediatric unit has been full the past week with babies with RSV, a respiratory illness.

Keegan announced Thursday that Regional Health, which has facilities throughout the Black Hills area, will issue a weekly report to area media with numbers of virus cases reported and recommendations for citizens about how to protect themselves.

The Regional Health virology lab in Rapid City researches viruses in the area.

"We're extremely fortunate to have a viral lab of this capability in a town of this size," Keegan said.

State epidemiologist Lon Kightlinger said seeing influenza peak during the month of February is normal.

Cases are said to peak when the most cases are reported and the influenza season then begins to retreat.

Kightlinger said there were 272 positive tests for influenza throughout the state over the past few weeks.

He said it is too soon to tell if the state's influenza cases are peaking because the data at the state Department of Health is not compiled until two weeks after cases occur. Hospitals are not required to submit case numbers to the department until a week after a patient is seen.

Kightlinger said that nationwide, over the last five years, 45 percent of influenza strains peaked in February. Nineteen percent of strains peaked in January, and 13 percent in December.

"In South Dakota, we pretty much see here what is being seen nationwide," he said.

Kightlinger said it depends on the year.

In some years, influenza cases peak abruptly; other years see more cases spread out over time, he said.

In South Dakota, the 2003 and 2004 influenza seasons peaked in the second week of December.

Usually, influenza cases start between Thanksgiving and Christmas.

In 2005 and 2006, the season peaked in the second week of March.

Kightlinger said it is never too late to get a flu shot, but he advises people to get them in October, not wait until later in the flu season.

He said someone who is vaccinated in February can still be vaccinated the following October because the shot will immunize against a different strain.

"People should just roll that into their regular fall routine: Rake your leaves, put up your Christmas lights, get your flu shot," Kightlinger said.

Kightlinger said frequent hand washing and observing good respiratory hygiene, such as sneezing or coughing into a tissue, are the best precautions to take against spreading influenza.

"I always insist to people if you're sick, stay home and take care of yourself," he said. "You need to get well, and you shouldn't be out there spreading viruses around."

Contact Katie Brown at 394-8318 or katie.brown@rapidcityjournal.com