Health officials in Texas are warning parents that more than 700 babies may have been exposed to tuberculosis at an El Paso hospital by an employee who worked in the nursery. The Providence Memorial Hospital employee tested positive for tuberculosis on Aug. 25, according to The Associated Press.

The warning applies to babies born at the hospital between Sept. 1, 2013 and Aug. 16, 2014, and includes families residing in Mexico and New Mexico, the El Paso Times reported. Parents were notified by letter this week, and offered free screenings and treatment.

"Your child should receive (a) TB skin test as soon as possible in order to determine if he or she has the TB germ," the Sept. 18 letter stated, according to the El Paso Times. "A nurse will look at the arm in 2-3 days to read the test. Your child will also need a chest x-ray so that a doctor can check to see if your children's lungs are clear."

New Mexico is home to approximately 50 of the 706 infants who may have been exposed and health officials in the state are offering TB screenings. About 40 hospital workers at Providence Memorial may also have been exposed.

The disease is contracted by breathing TB bacteria in the air. Common symptoms in children include cough, lethargy, weight loss, fever, and night sweats, but not everyone who is infected becomes sick, according to the Centers for Disease Control and Prevention. The agency says that infants and young children are more likely than others to develop life-threatening forms of TB, such as TB meningitis.