November 2006 volume 22 number 11 Genotyping Cluster of Tuberculosis Cases in Houston County, Georgia, 1997-2006 Background In September 2004, the Georgia Tuberculosis (TB) Program and the Georgia Public Health Laboratory (GPHL) began a universal genotyping project to identify TB strains with matching DNA fingerprints (or genotypes) circulating in Georgia. The project is part of a national effort led by the Centers for Disease Control and Prevention (CDC) to maintain a standardized database of all genetic TB strains in the United States. Detecting several TB cases with matching genotype strains, referred hereon as a genotype cluster, is useful for planning interventions to prevent the spread of TB since these clusters suggest recent or on-going disease transmission. This article describes such a cluster of cases reported from Houston County, Georgia from 1997-2006. Introduction From September-December 2005, the Augusta State Medical Prison (ASMP), a state-run facility under the Georgia Department of Corrections which treats all inmates with active TB in the state prison system, notified the Georgia TB Program of four TB patients who transferred to their facility from Detention Center X (DCX). The index case, who was a resident of Houston County, Georgia, developed TB-like symptoms two weeks before incarceration at DCX and was diagnosed with TB after two months at the detention center. Three inmates in DCX who were contacts of the index case were later diagnosed with TB. Three of these four patients had the same genotype as TB strains from six other Houston County residents in the state genotyping database. To determine how transmission occurred among the prisoners and residents in the community, a cluster investigation was conducted in accordance with CDCdeveloped guidelines (1). Methods Patient Interviews, Medical Chart Reviews and Health Provider Interviews We interviewed the three ASMP inmates who had matching genotypes using a CDC-developed TB Genotype Cluster Investigation Form and asked information on their places of residence, occupation, social history, and travel history in the past five years (1). We reviewed the medical records and contact investigation sheets of all the cases in the genotype cluster to determine any possible epidemiological links between them. We interviewed TB program coordinators and clinical staff in Houston County to collect information on possible social networks, occupations, locations, and risk behaviors that may have facilitated TB transmission among the cases in the genotype cluster. The Geographic Information System (GIS) Team of the Office of Health Information and Policy mapped the addresses of all genotype-matched cases using ArcView software. Laboratory Genotyping Analysis The GPHL submits all Mycobacterium tuberculosis isolates collected from TB cases in Georgia to a reference laboratory in California funded by CDC's Division of TB Elimination to perform genotyping. The isolates initially undergo two polymerase chain reaction (PCR)-based screening tests to identify possible genotype matches: spacer oligonucleotide genotyping (spoligotyping) is based on spacer sequences found in the direct repeat region in the Mycobacterium tuberculosis chromosome, while the mycobacterial interspersed repetitive units (MIRU) test analyzes DNA segments containing tandem repeated sequences in which different strains of Mycobacterium tuberculosis have different number of copies of the repeated sequence (1). When TB cases who have matching genotypes but do not have obvious epidemiological links such as common risk factors or shared time or space, or when routes of transmission among the cases are unclear, the GA TB Epidemiology Section requests a confirmatory test called restriction fragment length polymorphism (RFLP) to confirm a genetic match (2). For this investigation, the GPHL retrieved isolates of additional cases who the Houston County clinic staff suspected as being epidemiologically linked to this genotype cluster but who were reported before universal genotyping started in Georgia. These isolates were submitted for genotyping to determine if they belonged to the same cluster also. Results To date, 13 of 15 isolates from Houston County cases reported from 1997 to 2006 for which we requested RFLP confirmatory testing belong to the same PCR/RFLP cluster (designated in CDC's national TB genotyping database as GA_022A). Until recently, no other state in the U.S. or any other county in Georgia has reported this TB strain; however, in October 2006, an isolate that matched the GA_022A cluster was identified from a patient who lived in County B, 50 miles from Houston County. RFLP results are pending for two other isolates, and PCR testing has been requested for five more isolates from potentially linked cases reported in the mid-1990s. Among the 13 PCR/RFLP matched cases in Houston County, 11 (85%) are black, 10 (77%) are male, and the mean age is 40 The Georgia Epidemiology Report Via E-Mail To better serve our readers, we would like to know if you would prefer to receive the GER by e-mail as a readable PDF file. If yes, please send your name and e-mail address to Gaepinfo@dhr.state.ga.us. | Please visit, http://health.state.ga.us/epi/manuals/ger.asp for all current and past pdf issues of the GER. years (range: 22-62 years). Common epidemiological links among the cases include substance abuse, working in the construction industry, and incarceration. Nine (69%) cases have a history of illicit drug abuse, seven (54%) have a history of alcohol abuse, six (46%) worked in the construction industry (lawn work, painting, construction site clean-up, welding, sand-blasting, etc.), and five (38%) have a history of incarceration. Seven cases in this cluster live within a 0.8-mile radius of each other, 10 live within 1.7-miles, Figure 1. The epidemiologic relationships among cases in the GA_022A cluster are shown in Figure 2. Patient A is the index case from DCX and reported living, "hanging out", and "doing drugs" in the area where most of the other cases in this cluster reside. This area in Houston County is characterized by low socioeconomic conditions, the presence of several government housing complexes, and social problems such as drug trafficking, prostitution and trading sex for drugs. Several county clinic staff encountered problems with treatment compliance, mistrust of the health department, and misperceptions about TB skin testing from TB patients and their infected contacts in the area. Patient P is the newest case in the cluster reported from County B. This patient never lived or worked in Houston County, and possible epidemiological links to persons Georgia Houston County in the cluster are currently being investigated. Total 7 Cases Total 10 Cases Total 11 Cases Conclusion The ongoing transmission of a specific TB genotype initially limited to a small geographic area in Houston County, Georgia has recently spread to a nearby county, highlighting the importance of conducting genotype cluster investigations to prevent further transmission of TB. Although the cluster investigation did not identify specific epidemiological links between all of the patients, interpersonal interactions through substance/alcohol abuse, construction work, incarceration, and living in relatively close proximity to each other, may all have contributed to the transmission of this strain. The Georgia Division of Public Health's TB Program is exploring opportunities for educational outreach in the community in partnership with local social service agencies, community-based organizations and churches, to increase TB awareness and build trust between community residents and the public health system in this high-incidence area for TB. This article was written by, Nora Chen, Sc.M. and Rose-Marie F. Sales, M.D., M.P.H. References 1. National TB Controllers Association/CDC Advisory Group on Tuberculosis Genotyping. Guide to the Application of Genotyping to Tuberculosis Prevention and Control. Atlanta, GA: US Department of Health and Human Services, CDC; June 2004. 2. Goyal M, Saunders NA, van Embden JD, Young DB, Shaw RJ. Differentiation of Mycobacterium tuberculosis isolates by spoligotyping and IS6100 restriction fragment length polymorphism. J Clin Microbiol. 1997;35:647-651. Georgia Department of Human Resources Division of Public Health Office of Health Information & Policy 97 98 99 00 01 02 03 Created: October 2006 Source: Division of Public Health Projection: State Plane Georgia West Figure 2. Relationships of TB cases in the GA_022A cluster GA_022A Cluster Detention Center X Patient E Knew of each other in the construction industry Patient D Named Contacts Patient R Named Patient L Brother/sister Patient K Named Patient F Patient H Cousins Patient M* Patient A Patient C Patient B Legend Houston County case County B case Patient G Patient O Patient P *Matching RFLP but one digit difference in MIRU (PCR) Division of Public Health http://health.state.ga.us Stuart T. Brown, M.D. Director State Health Officer Epidemiology Branch http://health.state.ga.us/epi Susan Lance, D.V.M., Ph.D. Director State Epidemiologist Georgia Epidemiology Report Editorial Board Carol A. Hoban, M.S., M.P.H. Editor Kathryn E. Arnold, M.D. Cherie Drenzek, D.V.M., M.S. Susan Lance, D.V.M., Ph.D. Stuart T. Brown, M.D. Angela Alexander - Mailing List Jimmy Clanton, Jr. - Graphic Designer -2 - Two Peachtree St., N.W. Atlanta, GA 30303-3186 Phone: (404) 657-2588 Fax: (404) 657-7517 Georgia Department of Human Resources Division of Public Health Please send comments to: gaepinfo@dhr.state.ga.us 2006 Georgia Data Summary: LUNG CANCER Quitting smoking and avoiding secondhand smoke are the best strategies for preventing lung cancer. LUNG AND BRONCHUS CANCER Lung cancer is the most common cancer diagnosed in Georgia. Over 6,360 new cases of lung cancer will be diagnosed in 2006 in Georgia. Lung cancer accounts for 16% of all reported cancers. Age-adjusted Lung Cancer Incidence Rates, Females, by Health District, Georgia, 1999-2003 For females, the Northwest (1-1), North Georgia (1-2), and Coastal (9-1) Health Districts have significantly higher lung cancer incidence rates than the state average. For females, the DeKalb (3-5), and West Central (7) Health Districts have significantly lower lung cancer incidence rates than the state average. For males, the Northwest (1-1), North Central (5-2), East Central (6), West Central (7), South (8-1), Southwest (8-2) and Southeast (9-2) Health Districts have significantly higher lung cancer incidence rates than the state average. For males, the Cobb/Douglas (3-1), Fulton (3-2), East Metro (3-4) and DeKalb (3-5) Health Districts have significantly lower lung cancer incidence rates than the state average. Age-adjusted Lung Cancer Incidence, by Race and Sex, Georgia and the United States, 1999-2003 Rate significantly higher than the state average No significant difference Rate significantly lower than the state average Rate per 100,000 150 116 112 109 100 89 50 0 Black Males White Males Georgia United States 40 51 56 56 Black White Females Females Age-adjusted Lung Cancer Incidence Rates, Males, by Health District, Georgia, 1999-2003 Rate significantly higher than the state No significant difference Rate significantly lower than the state average RISK FACTORS Tobacco use (accounts for about 87% of lung cancers) Exposure to secondhand smoke Exposure to certain industrial substances such as arsenic, organic chemicals, radon, and asbestos Radiation exposure from occupational, medical, and environmental sources Air pollution PREVENTION Quitting smoking and avoiding secondhand smoke are the best strategies for preventing lung cancer. Data source: Georgia Comprehensive Cancer Registry (1999-2003) Date updated: June 2006 Publication number: DPH05.119H Visit http://www.health.state.ga.us/programs/gccr/index.asp for more information about cancer in Georgia. Georgia Department of Human Resources, Division of Public Health 2 Peachtree Street, NW Atlanta, GA 30303 (404) 657-3103 gdphinfo@dhr.state.ga.us http://health.state.ga.us -3 - The Georgia Epidemiology Report Epidemiology Branch Two Peachtree St., NW Atlanta, GA 30303-3186 PRESORTED STANDARD U.S. POSTAGE PAID ATLANTA, GA PERMIT NO. 4528 November 2006 Volume22Number11 Reported Cases of Selected Notifiable Diseases in Georgia Profile* for August 2006 Selected Notifiable Diseases Campylobacteriosis Chlamydia trachomatis Cryptosporidiosis E. coli O157:H7 Giardiasis Gonorrhea Haemophilus influenzae (invasive) Hepatitis A (acute) Hepatitis B (acute) Legionellosis Lyme Disease Meningococcal Disease (invasive) Mumps Pertussis Rubella Salmonellosis Shigellosis Syphilis - Primary Syphilis - Secondary Syphilis - Early Latent Syphilis - Other** Syphilis - Congenital Tuberculosis Total Reported for August 2006 2006 54 3430 31 5 75 1893 6 9 18 3 1 0 0 3 0 253 107 8 25 23 47 0 41 Previous 3 Months Total Ending in August 2004 2005 2006 197 236 164 9402 8574 9660 63 44 71 2 13 17 283 198 174 4468 4215 5216 23 19 19 77 49 25 122 47 50 16 11 10 5 4 5 1 5 1 0 0 3 5 18 10 0 0 0 828 728 683 166 138 310 20 34 21 129 140 85 83 102 79 232 240 165 1 0 0 122 140 128 Previous 12 Months Total Ending in August 2004 2005 2006 551 621 547 35029 33066 36484 160 154 214 21 29 40 890 796 675 16368 15696 17970 121 108 112 630 169 84 479 287 175 44 30 34 12 5 7 22 20 14 1 3 5 28 49 29 1 0 0 2087 1844 1922 717 538 1011 133 119 123 496 513 419 496 361 365 868 958 884 5 3 5 532 503 497 * The cumulative numbers in the above table reflect the date the disease was first diagnosed rather than the date the report was received at the state office, and therefore are subject to change over time due to late reporting. The 3 month delay in the disease profile for a given month is designed to minimize any changes that may occur. This method of summarizing data is expected to provide a better overall measure of disease trends and patterns in Georgia. ** Other syphilis includes latent (unknown duration), late latent, late with symptomatic manifestations, and neurosyphilis. Report Period Total Cases Reported* <13yrs >=13yrs Total Percent Female AIDS Profile Update Risk Group Distribution (%) MSM IDU MSM&IDU HS Blood Unknown Race Distribution (%) White Black Other Latest 12 Months**: 11/05-10/06 5 1,305 1,310 26.7 31.8 6.6 2.4 9.3 0.2 49.2 18.9 75.8 5.3 Five Years Ago: 11/01-10/02 1 1,543 1,544 26.6 38.1 7.6 2.9 18.9 0.8 31.7 17.5 77.2 5.3 Cumulative: 07/81-10/06 231 30,261 30,492 19.8 44.3 15.3 4.9 14 0.9 19.8 30.9 66.1 3 MSM - Men having sex with men * Case totals are accumulated by date of report to the Epidemiology Section IDU - Injection drug users HS - Heterosexual ** Due to a change in the surveillance system, case counts may be artificially low during this time period - 4 -