Use of tuberculosis genotyping for postoutbreak monitoring.
BACKGROUND
Review of routinely collected tuberculosis genotyping results following a known outbreak is a potential mechanism to examine the effectiveness of outbreak control measures.


OBJECTIVE
To assess differences in characteristics between outbreak and postoutbreak tuberculosis cases.


METHODS
Retrospective.


METHODS
United States.


METHODS
All tuberculosis cases identified as a result of >5-person outbreaks investigated by the Centers for Disease Control and Prevention during 2003 to 2007 (original outbreak cases), and subsequent culture-positive tuberculosis cases with matching Mycobacterium tuberculosis genotypes reported in the same county during 2004 to 2008 (postoutbreak cases).


METHODS
Proportion of demographic, social, and clinical characteristics of tuberculosis outbreak cases compared to postoutbreak cases. SECONDARY: Proportion of demographic, social, and clinical characteristics of epidemiologically linked versus nonlinked cases.


RESULTS
Six outbreaks with 111 outbreak cases and 110 postoutbreak cases were identified. Differences between outbreak and postoutbreak cases were gender (69% vs 85% male; P < .01), birth origin (3% vs 11% foreign-born; P = .02), disease severity (48% vs 62% sputum smear-positive; P = .04), homelessness (38% vs 51%; P = .05), and injection drug use (4% vs 11%; P = .04). For 5 of the 6 outbreaks, the status of epidemiologic relationships among postoutbreak cases was available (n = 89). The postoutbreak cases with a known epidemiologic link to the original outbreak were in younger persons (aged 39 vs 47 years; P < .01), and a larger proportion reported injection drug use (18% vs 4%; P = .04) or noninjection drug use (44% vs 18%; P < .01) than those without a reported link.


CONCLUSIONS
Health jurisdictions can utilize genotyping data to monitor and define the characteristics of postoutbreak cases related to the original outbreak.
Division of Tuberculosis Elimination, Centers for Disease Control and Prevention, Atlanta, GA, USA. rmiramontes@cdc.gov
Roque
R
Miramontes
Carla A
CA
Winston
Maryam B
MB
Haddad
Patrick K
PK
Moonan
D000293:Adolescent; D000328:Adult; D000368:Aged; D002487:Centers for Disease Control and Prevention, U.S.; D002648:Child; D002675:Child, Preschool; D046508:Culture Techniques; D004196:Disease Outbreaks / Q000517:prevention & control* / Q000706:statistics & numerical data; D004641:Emigration and Immigration / Q000706:statistics & numerical data; D005260:Female; D060005:Genotyping Techniques; D006703:Ill-Housed Persons / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D017053:Infection Control / Q000592:standards; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology / Q000379:methods; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000302:isolation & purification; D012150:Polymorphism, Restriction Fragment Length; D011159:Population Surveillance; D015995:Prevalence; D011329:Prisoners / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D013183:Sputum / Q000382:microbiology; D015819:Substance Abuse, Intravenous / Q000453:epidemiology; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology; D014481:United States / Q000453:epidemiology