New Round of TB Tests Ordered at High School : Disease: 18 students, two teachers at La Quinta test positive for the bacteria after coming in contact with a student who suffered a relapse.

Orange County’s top health official said Wednesday that he is ordering a second schoolwide tuberculosis screening at La Quinta High School upon discovering that 18 students and two teachers have tested positive for TB bacteria after coming in contact with a student who suffered a relapse of the disease.

Skin testing of about 1,300 students and staff members at La Quinta will begin Monday, said Dr. Hugh Stallworth, County Health Officer. Those who have positive skin tests, meaning they have been exposed to the bacteria, will receive chest X-rays later in the week to help determine if they have active disease.

“We are planning a full-court press and we would like to do it within a week before school closes,” Stallworth said.

Parents will be informed of the weeklong testing by two letters, one mailed and the other sent home with students on Wednesday, said La Quinta’s principal, Mitch Thomas. Stallworth said that, based on X-ray results so far, none of the students or teachers who have newly tested positive for the TB bacteria have the disease, although a 10% chance exists that they will develop active TB in their lifetime. About half that risk, he added, is concentrated in the first two years after exposure.

Stallworth said the new TB threat at La Quinta is “very serious” because Debi French, the senior who suffered the relapse, came down with a new strain of TB that is resistant to all the first-line antibiotics used to fight it.

French was admitted to a Denver hospital specializing in hard-to-treat tuberculosis cases, and on Tuesday a third of the 18-year-old’s right lung was surgically removed in the battle to cure her.

French was one of 17 La Quinta High School students to have contacted tuberculosis since 1991. In a series of TB screenings, capped with schoolwide testing last fall, health authorities determined that 12 of the students had a drug-resistant strain. All were put on treatment to make them non-contagious. Only French has had a relapse, county health officials say.

Stallworth said it is believed that French was contagious between December and February. Moreover, a sputum culture revealed she had developed a new strain of TB that was resistant to even more drugs.

Immediately after French’s relapse was diagnosed, Stallworth said, county health workers tested 88 students in her senior class and five staff members, with five students showing positive results. Earlier this month the entire group was retested and 13 more students and two teachers had positive skin tests.

The testing will be mandatory, health officials said, and any students who refuse to participate will be kept out of school.

After last year’s screening at La Quinta, 175 students found with positive skin tests were put on medications that substantially reduce the risk that the disease will become active later.

However, Stallworth acknowledged it is far less certain what preventive medications to give students who may have been exposed to the multidrug-resistant variety of TB that French has. “We are getting into uncharted waters here,” he said.

Stallworth said the Centers for Disease Control in Atlanta has advised that those who test positive for multidrug-resistant TB may ward off the disease by adopting a healthy lifestyle. But he said he will recommend that parents also have their children take a combination of two medications. “I realize parents are going to be very concerned, very upset, some even very frightened,” Stallworth said. “We are doing all we can with the school district to allay any fears. . . . There is no reason for alarm. We just need to investigate and see where we are with this.”