The DeKalb County Health Department will administer the flu vaccine only to DeKalb County residents deemed to be at the highest risk for influenza complications.

“We’re receiving a limited supply,” said Jane Lux, director of the Personal Health Services Division at the DeKalb County Health Department. “There was no more vaccine available.”

On Dec. 9, the health department announced its vaccine supply was gone. University Health Service said it has been out of the vaccine “for quite some time.”

Lux said there was a high demand nationally for the vaccine earlier in the flu season, which led to the limited availability.

The vaccine will be available at 9 a.m. Thursday at the health department clinic, 2550 N. Annie Glidden Road. The cost is $10 for adults 19 years of age or older and $8 for children under the age of 19.

About 5,000 people in the county have received the vaccine since the department started distribution in October, Lux said.

Biology professor Jozef Bujarski said the flu virus’ genetic information is composed of different ribonucleic acid (RNA) fragments.

The fragments recombine to form different strains of the virus, Bujarski said. This can produce up to 10 to 12 different strains each year; however, only two or three strains become dominant. Scientists analyze which strains are dominant and they synthesize vaccines to combat the disease.

“[Flu vaccines] are reliable, provided they are against a particular strain in a given year,” Bujarski said. “It’s a constant fight between the human beings’ inventions and the virus’ genetic inventions.” New variants also might develop in the middle of the flu season.

Vaccines typically are given out in October and November, and the season runs from November to April, with a peak in January to March, according to the health department. It takes about two weeks for immunity to develop.

Side effects may develop from the vaccines, including soreness at the site of the injection, low-grade fever or possibly an allergic reaction, Lux said.

However, Lux pointed out that there are no complications from the shot.

“You can’t get the flu from a flu shot,” Lux said. “That’s a myth we try to dispel.”