Title of Thesis: CONVERSION AND REVERSION OF TUBERCULIN SKIN AND QUANTIFERONGOLD-IN-TUBE TESTS AMONG PERSONS EXPERIENCING HOMELESSNESS DURING A MULTI-SHELTER SCREENING EFFORT IN ATLANTA, GEORGIA (2008-2018) 

Thesis Chair: Heather Bradley, Ph.D., MHS

Background:  The aim of this study was to describe the proportions and risk factors associated with conversion from a negative tuberculosis (TB) screening to a positive screening result and reversion from a positive to a positive TB screening among  persons experiencing homelessness (PEH) screened during the control efforts for a multi-shelter TB outbreak in Atlanta, GA. 

Methods: A retrospective analysis of TB screening among PEH residing in Atlanta’s homeless facilities was performed for latent tuberculosis infection (LTBI) by TST and QFT between 2008 – 2018.
 
Results: Out of 16,745 PEH screened by TST or QFT, 1,607 (9.6%, 95% Confidence Interval [CI] 9.2 – 10.1%) PEH had a positive TB screening at their initial screening encounters. Factors associated with having an initial positive TB screening result were older age, being male, being Asian, HIV co-infection and history of incarceration. Among those who were negative at initial screening and received a subsequent TB screening test (total person time of 102,923 person months), 8.5% (298/3,504) became positive, corresponding to a rate of 2.9 positive screenings conversions per 1000 person months. The rate of conversion was significantly higher among male, older adults and PEH with HIV. Among the 1,607 individuals with positive TB screening at initial screening encounters who had a subsequent TB screening (total person time of 6,655 person months), 36.5% (88/241) reverted to a negative screening result, corresponding to a rate of 13.2 reversions per 1000 person months. The rate of reversion was significantly higher among older adults and those screened using TST at the initial screening encounter. 

Discussion: Persons experiencing homelessness are at increased risk of active TB disease. Routine screening and re-screening will help identify individuals who acquire TB infections during shelter stay and help improve treatment in affected persons.