A case of tuberculosis has been confirmed at a Gwinnett County high school.

In a letter sent to parents Friday, the principal of Discovery High School said a student has been diagnosed with the disease and is undergoing treatment.

“The Gwinnett County Health Department has told us the most important thing to remember is that tuberculosis is a disease that is hard to spread to others,” Marci Sledge said in the letter. “Close and continuous contact over hours is generally necessary for transmission of the disease to another person.”

Tuberculosis, or TB, is an infectious disease that mainly affects the lungs, according to the Mayo Clinic. The bacteria that cause tuberculosis are spread from one person to another through tiny droplets released into the air via coughs and sneezes.

RELATED: What is tuberculosis?

The school worked with county health officials to determine which students and staff had contact with the infected student, according to the letter. According to the school district, about 226 students and staff could have been in “close and continuous contact” with the infected student.

Sloan Roach, a spokeswoman for Gwinnett County Public Schools, said school is operating as normal Monday. Because of the way the disease is transmitted, the school’s normal cleaning processes were sufficient, she said.

Free tuberculosis skin tests will be offered to those individuals at the school Wednesday. A separate letter with information about the process was sent to affected students and staff, Roach said.

This is the latest case of tuberculosis in Georgia.

RELATED: 2 cases of tuberculosis confirmed at Floyd County elementary schools

The Floyd County School District said Thursday the Georgia Department of Public Health notified it of one confirmed case at Model Elementary School and one at Johnson Elementary School. Both schools were cleaned Thursday.

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