OLATHE, Kan. -- More than two dozen people have been infected with tuberculosis at a high school in eastern Kansas, CBS Kansas City affiliate KCTV reports.
The cases were identified after widespread screening, state and county health officials announced Wednesday.
More than 300 Olathe Northwest High School students and staff members were tested after coming into contact with an infected student. In addition to that student, the testing revealed 27 new cases of TB that hadn't progressed to the contagious stage, the Johnson County Health Department said in a news release.
Officials don't know when or how that first student became infected.
Officials began calling the people who tested positive on Monday, while those with no sign of infection will receive letters, the department said.
"The number of individuals with TB infection does not exceed what we would anticipate in this setting," health department director Lougene Marsh said in the statement. "Of course, we had hoped we wouldn't find any additional TB cases, but we knew this was a possibility. That's why we took such thorough steps to test everyone who might have been in close contact with the first confirmed case of TB disease."
Tuberculosis is an infectious disease that attacks the lungs and can be fatal if not treated with antibiotics. It is generally spread by coughing and sneezing. Symptoms include a bad cough for three weeks or longer, chest pain, weakness or fatigue, and coughing up blood.
Individuals who tested positive for the infection will get chest X-rays and begin treatment with antibiotics to kill the TB bacteria and prevent the development of the disease.
Blood tests will be repeated on May 5 for those contacts who were identified as exposed to TB disease during the spring semester of the school year. This second test is necessary as it can take up to eight weeks for the bacteria to show up positive in a TB test.