Table 2.

Factors contributing to TB outbreaks for which the Centers for Disease Control and Prevention provided on-site assistance, United States, 2002-2015

	No. of Outbreaksa
Characteristics	2009-2015	2002-2008b
Total	21	27
Delays in TB diagnosisc	20	12
Patient delay in seeking care for symptoms	16	6
Delay in diagnosis once under medical care	14	12
Nonadherence to treatment	7	5
Congregation of high-risk populationsd	12	7
Overnight homeless facilities	8	—e
Local jails	8	—e
Prisons	2	—e
Residence for people with mental disability	2	—e
Health care facilities	2	—e
Otherf	7	—e
Incomplete contact investigations	13	10
Contacts not identified	7	—e
Contact investigation not expanded	6	—e
Contacts identified but not evaluated	8	—e
Contacts evaluated but infection not treated	3	—e

Abbreviation: TB, tuberculosis.

^aCategories not mutually exclusive.

^bData for 2002-2008 were previously reported.²

^cData concerning delays in TB diagnoses considered to be >2 months between symptom onset and the date that the patient began TB treatment.

^dNumbers may exceed the number of outbreaks because several outbreaks involved >1 congregate setting.

^eData concerning these characteristics were not collected for the 2002-2008 outbreaks.

^fOther facilities included drug houses (n = 4 outbreaks), workplaces (n = 2 outbreaks), and a school.