Misdiagnosed teacher's health scare unveils TB detection challenges

In the waning summer days of 2014, elementary school teacher Laura Hall felt drained by a cough that wouldn’t go away. It was related to acid reflux, she was told, and should be treated with antibiotics. But despite taking the prescribed medications, her symptoms worsened. 
 
Eventually, Laura's mystery ailment would lead to three months of quarantine and to a contact investigation of more than 500 individuals. QuantiFERON-TB Gold Plus, a state-of-the-art blood test, could have detected the teacher’s infection before she became sick and put others around her at risk. 
 
Laura Hall lives in the small town of Shelburne, Vermont, close to the Canadian border. When she suspected she was coming down with the flu, she sought medical advice, but was given the same diagnosis from the various doctors she consulted.  

“I had the chills at night, my energy level was going down, and I kept losing weight,” recalls Hall. “I became more and more worried, because nobody could really help me.” 

During the Christmas holidays, she went to the emergency room where the attending physician finally solved the mystery. 
 
Hall was diagnosed with active tuberculosis, or TB, a contagious disease that had eluded all her previous medical caregivers.  

“It was absolutely shocking,” says the Spanish teacher. “I kept asking, ‘Are you sure?’ I just couldn’t believe it, because I had not been near anybody with TB.”

Millions of latent infections 

What Hall didn’t know was that, like hundreds of millions of people around the world, she had carried a latent TB infection (LTBI) – and had probably lived with it for years before it became an active infection.  

Once her latent TB progressed to active infection and her cough arose, she unknowingly exposed hundreds of students, teachers, friends and family members to the airborne pathogen.  

“What worried me most was that I had worked at my school right up to the holidays,” Hall says about her harrowing experience. 

Her experience isn't rare. Tuberculosis is a leading cause of death from infectious diseases, claiming 1.6 million lives annually, or one every minute.  

Around a quarter of the global population, including an estimated 13 million in the US, carry LTBI, which often remains symptomless but can develop into contagious TB, especially in those with weakened immune systems. 

Although only 10% of those with LTBI develop active TB, early prevention is crucial. People like Hall usually don't get diagnosed until their LTBI advances to active TB due to its silent nature. 

Vermont's public health officials reacted quickly to Hall's case, initially hospitalizing her for four days and then implementing a three-month home quarantine. 

Making headlines 

As her story gained media attention, authorities took action to address community concerns. The Vermont Department of Health conducted TB screenings for about 500 people who might have been exposed, with 21 testing positive for LTBI using the QuantiFERON®-TB Gold blood test, a method more precise than traditional skin tests. 

Born in Peru, Hall was vaccinated against TB in childhood with the BCG vaccine and underwent regular tuberculin skin tests throughout her career, which failed to detect her latent TB. 

This issue has been recognized globally, leading to changes in screening practices. In early 2018, the WHO revised its guidelines for latent TB screenings, and the CDC now requires blood-based TB tests for immigration screenings, acknowledging the limitations of older skin tests. 

Addressing TB in its latent stage is key to halting its spread, and effective screening is vital. The adoption of the CDC's new guidelines for latent TB screening could prevent situations like Hall's. Dr. Michael Lauzardo, a lung disease expert at the University of Florida Health system, supports this approach. “With the increased precision of this blood test, you take the whole issue of vaccination out of the equation.” 

Lauzardo notes that requiring blood tests for immigration screenings is an “exceptionally effective strategy.” He points out the skin test's drawbacks, especially for those from high TB-prevalence countries: “This can lead to people being put unnecessarily on medications, which consume public health resources and can cause side effects." He also mentions that false positives in BCG-vaccinated individuals can lead to complacency: “As a result, they don’t seek treatment.” 

Hall, having experienced TB firsthand, now views infectious diseases differently. “Anybody can get TB, so when that cough won’t go away, think about getting tested,” she advises. She returned to teaching after three months but confesses the experience took a psychological toll. “I felt ashamed and worried for my students,” she says, expressing gratitude for their welcoming attitude post-recovery. “I am so grateful that they all made me feel welcome again after my ordeal.”