SELLERSBURG, Ind. (AP) — Nearly 50 southern Indiana students exposed to a classmate with a confirmed case of tuberculosis have tested positive for the disease in preliminary tests.

Clark County Health Department administrator Mike Meyer said Friday the 48 positive skin tests for the bacterial disease don’t mean those students have diagnosed TB cases.

He says the Rock Creek Community Academy students will undergo chest X-rays and possibly other tests to determine if they have the illness.

Dr. Paul Schulz with Norton Hospital in Louisville, Kentucky, tells WAVE-TV the students could have latent tuberculosis, where the person isn’t ill or contagious but could eventually develop TB.

Tuberculosis bacteria typically attack the lungs, but can infect other organs. TB can be deadly if left untreated. The bacteria are typically transmitted through coughs and sneezes.