FAIRFIELD, Calif. (KTVU) -- A tuberculosis case is causing a ripple effect at a Solano County high school.
One person has been diagnosed, and now dozens of others who had ongoing contact with that patient will be contacted.
"We'll be testing over 200 people," said Dr. Michael Stacey, at a news briefing late Thursday.
Stacey is the Deputy Health Officer for Solano County.
Due to patient privacy, he would not reveal if the sick person is a student or a staff member.
But he described the individual as an "integral part" of the campus community, who had regular contact with many people.
The patient is recovering at home, and in isolation to avoid infecting others.
Now, those he or she interacted with most at school will have blood drawn and tested for tuberculosis.
"It's not something you get in passing in a hallway," explained Stacey, "it's spending prolonged time in an enclosed space with the individual."
Tuberculosis is a slow- growing respiratory disease, which spreads through the air.
It is stubborn to treat, and potentially fatal if untreated.
Experts emphasize, even if someone tests positive, if the infection is latent, not active, it's readily knocked out.
"We expect that we'll identify those individuals before they have active disease and before they're contagious," predicted Stacey.
Parents are receiving recorded phone messages, and a letter has been mailed to Armijo households, explaining the situation.
"I'd want to know if my daughter is in any of those classes," parent Hemina Patel told KTVU, as she waited for her sophomore student outside school.
"It's brand-new and a little bit of a shock," she added, "so at this point I guess we're just waiting for more information."
Such scares aren't unheard of in high school settings. Last fall, a student at Skyline High school in Oakland was diagnosed with TB, setting off the same response, identifying and testing his circle of close contacts.
"None of us knew about it, today was just another school day," Armijo senior Pedro Sanchez told KTVU. "We haven't been told anything yet, but hopefully tomorrow."
Sanchez says he's concerned and wonders if his asthma makes him more susceptible.
"In biology, we learned about tuberculosis and how badly it can affect people, so knowing it's around, I'm going to look out for my health," he declared.
The few hundred people who need testing will get their blood drawn on campus, and be able to remain at school as results take a few days.
"We're being as open and transparent as we can," reassured school principal Eric Tretton, at the news briefing.
On a campus of 2500 students and staff, Tretton knows there are questions.
"Our goal is to answer them as best we can, be forthright, and hopefully relieve anxiety over this."
Next Tuesday night in the gymnasium, families are invited to a presentation on tuberculosis, and an opportunity to ask questions.
Solano County is monitoring between twenty and thirty active cases of tuberculosis every year.
The school district has scheduled a town hall meeting next week to answer questions about the incident. The event will be held Tuesday, Feb. 21 from 6:30 p.m.-7:30 p.m. in the gymnasium at Armijo High School, located at 824 Washington St. in Fairfield.