The Illinois Department of Public Health this morning raised the number of confirmed cases of the swine flu virus to 82, including 34 in Chicago.

That's up from five confirmed Chicago cases as of yesterday morning.

Officials are also monitoring an additional 40 probable cases of the H1N1 virus in the state, and 15 in the city.

Though the number of cases continues to climb, officials say they are heartened by the low death rate for those infected. The CDC also says the virus appears to have a genetic structure similar to the common flu, rather than deadlier types.

“The large increase in the number of confirmed cases was expected and is not cause for alarm," says Dr. Damon Arnold, director of the Illinois Department of Public Health.

Part  of the rise comes because the state is now able to quickly confirm swine flu cases without sending samples to federal labs.

Tim Hadac, spokesman for the Chicago Department of Public Health, says officials there continue to be vigilant. Some epidemics, including the 1918 outbreak that killed millions, involved viruses that were first easily controlled and then mutated into more dangerous forms. 

"Always in public health, you hope for the best and prepare for the worst," he says.

Hadac says epidemiologists from the CDC arrived in Chicago today to study the virus and the way it has affected Chicagoland.

"In Chicago [and] the region, it's clear that the virus is circulating generally throughout the community," Hadac says.

The CDC team, he says, is working with CDPH to better understand the virus.

"What they learn from this will help the city and the nation with future outbreaks, especially if there's a second wave," he says.

Kilmer Elementary School in Rogers Park, closed last week because a student contracted swine flu, remains closed.

Officials continue to encourage people to cover their mouths when sneezing or coughing, wash their hands, stay home when sick and teach those habits to others.