A Merced High School student has been diagnosed with tuberculosis, Merced County Health Department officials confirmed Thursday.
The risk for other students to contract the disease is "very low," according to a statement sent out to parents and staff last week by the high school.
Up to 200 students and staff were notified they may have had "prolonged" exposure to the student diagnosed student and will be tested, said Richard Rios, public health program manager for the Merced County Department of Public Health. The health department started doing screening tests on campus Wednesday.
Tuberculosis, commonly known as TB, is a disease caused by bacteria that usually attacks the lungs, but can attack other parts of the body like the spine or brain, said Daniel Diep, regional medical director of Golden Valley Health Centers. The disease is contagious and spreads through the air from person to person.
"This can happen whenever a person with active TB disease in the lungs coughs or sneezes," Diep said in an email to the Sun-Star. "People nearby the person with TB may breathe in the bacteria that gets into the air and then settles into the lungs."
Based on the health department's investigation “we know there was a possibility there was exposure to people on campus while this case was considered infectious,” Rios said in a phone interview with the Sun-Star. "The health department has been working as timely (as possible) with campus and district officials to perform indicated follow up actives.
The high school was notified of the diagnosis on March 12 by the Merced County Health Department, said Cristi Hinds, director of student support services for Merced Union High School District. All the required notices were given to the school by the health department the next day, she said, and they notified parents and staff on March 15.
Notices also were sent out in Spanish and Hmong, Hinds confirmed.
Last year, there were seven cases of TB reported in Merced County, Rios said, and during the past 10 years, Merced averages 10 cases a year. TB rates across the county, state and country have been dropping, he added.
The case reported last week marks the first of 2018 in Merced, officials confirmed.
Not everyone infected with TB bacteria becomes sick, Diep said. Some may have a latent TB infection and will not feel sick. Those with a latent infection cannot spread the disease to others.
The disease can be life-threatening if people aren't treated properly, Diep added. People with active TB "must take medicine for several months."
According to the Mayo Clinic, symptoms for active TB include: coughing that lasts three or more weeks; coughing up blood; chest pain, or pain with breathing or coughing; unintentional weight loss; fatigue; fever; night sweats; chills and loss of appetite.
Saturday is World TB Day and Merced County Health Department officials urge the public to learn the signs and symptoms of TB. For more information, contact a doctor or the health department at 209-381-1023.
This story has been corrected from an earlier version.
Monica Velez: 209-385-2486, @monicavelez21