A genotypic match between TB specimens identified in this cluster was considered indicative of cluster-associated
transmission.
We defined active TB cases as:
• Confirmed – TB disease with G03483 genotype reported in a Clark County, Nevada,resident during January 1, 2013–December 10, 2013.
• Probable – TB disease with unknown genotype reported in a Clark County, Nevada,resident during January 1, 2013–December 10, 2013, where an epidemiologic linkage to one of the active cases identified through this investigation exists.
• Suspect – suspected TB disease (clinical indications of TB disease, final diagnosis pending) reported in a Clark County, Nevada, resident during January 1, 2013–December 10, 2013, where an epidemiologic linkage to one of the active cases identified through this investigation exists.
Identifying Persons with Indications of LTBI
A contact with LTBI is defined as a person who had a positive test (tuberculin skin test (TST), Quantiferon-TB tests (QFT), or (T-SPOT test), but is asymptomatic and had a negative chest radiograph. We recommended treatment to persons diagnosed with LTBI.