LAS VEGAS (AP) -- Las Vegas public health officials say dozens of people linked to a tuberculosis outbreak at a neonatal unit have tested positive for the disease.
The Southern Nevada Health District reported on Monday that of the 977 people tested, 59 showed indications of the disease, though all but two of the cases are latent — meaning patients don't show symptoms and aren't contagious.
Dr. Joe Iser, chief medical officer at the health district, said the report demonstrates the importance of catching tuberculosis early.
"We want physicians to really think about making the diagnosis and quarantining, and then calling us," he said. "This has been very expensive for us in terms of time and effort and dollars."
A state report released last month found that Summerlin Hospital Medical Center failed to recognize and take precautions to diagnose the infected woman's contagious lung disease when she gave birth in May to premature twin daughters, and allowed the woman to continue visiting her babies after she was discharged.
One of 25-year-old Vanessa White's babies died in June. White died in July at a Los Angeles hospital and was diagnosed with tuberculosis through an autopsy. Her other baby died of tuberculosis on Aug. 1 at Summerlin Hospital.
Iser said officials cannot know for sure that all 59 cases are directly linked to the Las Vegas hospital. Several of those tested are immigrants from countries where tuberculosis is more prevalent, and could have been exposed earlier in their lives, he said.
The health district is encouraging all 59 people to accept treatment.
TB is spread through the air when a sick person coughs, sneezes or speaks. Symptoms include coughing, chest pain, fever and fatigue. The disease usually attacks the lungs, but can affect other organs and can be fatal if not properly treated.
The Centers for Disease Control and Prevention counted 569 TB deaths in the U.S. in 2010, the most recent year for which data is available. The number of U.S. TB cases has been on a steady decline since a resurgence in 1992, and in 2012, reached the lowest level since national reporting began in 1953.
The Nevada Bureau of Health Care Quality and Compliance investigated the case, and determined that the Las Vegas hospital wasn't taking proper precautions to contain infections.
In November, eight employees, former patients and visitors filed a negligence lawsuit seeking damages from the hospital. Family members of the young mother who died of the illness have said they also plan to sue.
In the fall, investigators found that 26 people, including the mother's family members and hospital staff, had been infected.
Health officials then tested hundreds of babies, family members and staff who had passed through the neonatal intensive care unit. They contacted the parents of about 140 babies who were at the unit between mid-May and mid-August, and set up a temporary clinic to test them.
Health officials are expected to release a final report next summer.
They will continue to test the infants who passed through the hospital in the coming months, to ensure the babies don't develop any signs of the disease.
"I try to think, what if it was my son or daughter, my newborn infant, what would I want to be done?" Iser said.
Hannah Dreier can be reached at http://twitter.com/hannahdreier