A 55-year-old DeKalb County male has been infected with the West Nile virus, but has not been hospitalized.

The infected male has shown signs of less dangerous flu-like symptoms consistent with the virus, including muscle aches and nausea.

DeKalb is the 17th county in the state of Illinois to report a case of the mosquito-born virus in a human.

The DeKalb County Health Department has stressed that there is no need for local residents to panic.

If five people are bitten by infected mosquitoes, only one of those people will show symptoms of the virus, said Karen Grush, DeKalb public health administrator. Of those who show symptoms, only one in 150 people will develop the lethal form of the disease.

“There is a risk, but not a great risk,” said Dianne Cerlock, professor of clinical sciences.

The older an infected individual is, the greater the chance for the full-blown virus called encephalitis, Cerlock said. Encephalitis irritates the brain case and tissue surrounding the brain. Those who are younger and have intact immune systems probably won’t be affected as badly, she said.

The virus has a tendency to affect individuals over the age of 50. Of the 165 cases, 119 infected people were over the age of 45. The average age of infected Illinois residents is 56.

“There have been younger people infected, but the majority of people infected are much older,” Grush said.

It is not necessary to have developed symptoms from the minor condition of the disease to develop encephalitis, Cerlock said.

The consequences from the virus can include stupor, convulsions, paralysis and in some cases, death.

DeKalb County will stick with its original plans to combat the virus, including the larvae-sizing of the water catch basins. The larvae-sizing may kill the mosquito larvae before they become fully active adult mosquitoes.

The Health Department suggests that people should remove standing water from their properties where mosquitoes breed.

Illinois has the second highest number of reported cases of the virus in the country, totaling 165 to date.

In the past three months, DeKalb has reported six birds with the virus. Mosquitoes that bite infected birds then can carry the virus and infect human beings.

“The most important thing to remember is that it is the people’s responsibility to protect themselves in the evening hours from getting a bite,” Grush said.

The Associated Press contributed to this report.