Targeted Tuberculosis Screening in Response to a Retrospective Analysis of Genotyping Data and GIS Data

State: TX Type: Model Practice Year: 2004

Tuberculosis is an important health problem among the community's homeless population. In light of this problem, all of the individuals that stay at the Presbyterian Night Shelter must now undergo a required chest x-ray and tuberculin testing and reading prior to their admission into the shelter. The outcome of this practice has been a decrease of tuberculosis morbidity within the homeless population. The key elements needed to replicate this program include developing a working relationship with shelter directors and enforcing the required chest x-rays and tuberculin skin testing and reading prior to admission to the shelter.
Tuberculosis is an important health problem among the community’s homeless population. Since 1991, the Tarrant County Health Department has performed active surveillance screenings at the local homeless shelters with some success, averaging one active case per 100 chest x-rays performed. At that time, screening and medical evaluation was offered on a voluntary basis. Between September 1999 and March 2002, only two cases were identified out of 2911 chest x-rays. Between January 1, 1993 and December 31, 2000, 29 cases identified living in the shelter were linked genetically using molecular genotyping techniques. Another nine cases were identified that did not match any other case. Furthermore, a study showed that, of the cases detected among homeless individuals, only 5.3 percent were detected by voluntary active case-finding screening methods at the shelters. The remaining 94.7 percent were detected in area hospitals. This suggests that a significant number of homeless may remain in the overcrowded setting of the shelter until they are seriously ill. This behavior threatens to propagate ongoing transmission and to increase effective reproduction and the number of future cases. The health department responded to this situation by partnering with the Presbyterian Night Shelter (PNS) board of directors and developing an enforced TB screening program. The health department staff performed a retrospective analysis of all culture-confirmed cases in Tarrant County that underwent molecular characterization for the detection and genotyping of specific strains of tuberculosis. The retrospective analysis of this genotyping data, plus geographic informational system (GIS) data, suggested that ongoing transmission was occurring in the Presbyterian Night Shelter. This discovery prompted the TCHD to rethink its surveillance strategy. In collaboration with the PNS executive board of directors, the health department designed a new surveillance program.
Agency Community RolesTarrant County Public Health Department Tuberculosis Division is the lead agency in this endeavor. The Health Department works in collaboration with staff from the University of North Texas Health Science Center at Fort Worth. The Texas Department of Health provided the funding for the project. The PNS staff help by enforcing the required chest x-rays and tuberculin testing and reading before an individual was admitted into the shelter. The department presents the information gathered to the PNS board of directors. Department staff also discuss problem areas with the board, and they work together to resolve these issues. Each time information is shared, it is clear that this type of screening is making the shelter a safer place for the residents, staff, and board members. This strengthens the board’s resolve to help meet the practice goal. Costs and ExpendituresAs part of the contract with the PNS, the Health Department agreed to pay PNS at a rate of $15 for each new resident that received a chest x-ray and completed the screening process, and $20 for each case that was identified and completed adequate therapy, up to the amount of $10,000. The funds were to be used to improve the night shelter. As for personnel costs, the health department was already screening at PNS on a regular basis. The time spent by the physicians, nurses, clerks and the x-ray technician was already scheduled for the regular screenings. The only additional staffing cost for this project was providing two outreach workers for four hours Monday through Friday to provide the Directly Observed Therapy (DOT) and Directly Observed Preventive Therapy (DOPT). One of the outreach workers is paid by the Federal TB Outreach Grant, and the other is paid from the TBTC research grant monies. So there were no additional staffing expenses. The program does spend an increased amount for film and processing fluid, and has averaged a 65 percent increase in the number of x-rays taken during each screening. The average cost for one film plus development is $1.15. On an average night, 100 residents are screened, a cost of $115 for film and processing fluids. This cost of film is covered by the Federal Outreach Grant and by Tarrant County. The Tarrant County match for the federal grant is 38 percent. ImplementationGrant monies were requested from Texas Department of Health. A contract was developed with the Presbyterian Night Shelter. PNS agreed: Not to permit individuals to stay at PNS until each individual had signed consent forms and taken required tests and x-rays. To help the health department personnel locate residents with abnormal chest x-rays. To help the health department personnel locate residents for tuberculin skin test readings. To help the health department personnel locate residents for DOT, DOPT, and baseline and monthly liver function tests. To help TB staff members locate residents for contact investigations. The screening began in September of 2002, and the data reflect results through December of 2003. The project continues today and has expanded to the other homeless shelters in Fort Worth.
From September 2002 to December 2003, 1,700 homeless individuals were screened at the Presbyterian Night Shelter, and 17 active cases were identified and treated, 15 individuals were identified with old tuberculosis non-active, and over 170 individuals with latent tuberculosis. All of these individuals were placed on DOT or DOPT. Challenges that staff encountered included angry residents, who were educated about tuberculosis and given an explanation of the risk of not screening everyone, and residents with mental illness. Program staff worked with the PNS staff members to find out what methods they used in dealing with individuals with mental illness. Many times having someone they were familiar with made them more comfortable with the screening process. The staff also used incentives. Having residents return for Tuberculin Skin Test reading was often a challenge. Many individuals were tested more than once. The health department decided to have the outreach workers that were providing the DOPT also available to read skin tests. This approach increased the number of readings and decreased the number of repeat test needed. In spite of these challenges, from December 5, 2003 to February 26, 2004, after screening six times, no active tuberculosis cases and suspects were found, indicating a decrease in tuberculosis morbidity at the Presbyterian Night Shelter. In comparison, from 2002 to 2003, multiple cases and suspects were identified. The health department is convinced that if the required tuberculosis screening had not been instituted direct transmission of tuberculosis would have continued.
SustainabilityAs the PNS board of directors became aware of the number of cases and the large number of individuals with latent tuberculosis, their commitment grew. Each time they go to the shelter, they see the staff providing DOT and DOPT. This is a constant reminder of why enforced screening is necessary. The homeless population will continue to need screening. As long as there is adequate staffing and funding, the plan is to continue to screen this high-risk population. Lessons LearnedWhen trying to implement this type of project, having strong data helps to sell the idea. Program staff also asked for suggestions from the stakeholders on how they thought the project could be implemented. This resulted in their buy-in from the beginning.