Homelessness is a risk factor for TB

In 2011, the reported number of tuberculosis (TB) cases decreased to 10,528 from 11,171 in 2010. Among those affected, disproportionately higher rates of TB occur among high-risk populations, especially homeless persons. In the United States, 1% of the population experiences homelessness in a given year, but 5.8% of persons with TB reported being homeless within the past year. These findings are not surprising, as persons who are homeless have a high prevalence of conditions that increase the risk of TB, including substance abuse, HIV infection, and residence in crowded shelters. This combination of conditions is conducive to transmission of TB. Persons who are homeless often lack ready access to the medical care required to make an early diagnosis of TB.
Chart 1: In 2011 there were 10,528 new cases of tuberculosis in the United States. Of those, 9,814 were cases ≥15 years or older with information on homeless status. Of those cases, 565 were reported as being homeless.

Chart 1: In 2011 there were 10,528 new cases of tuberculosis in the United States. Of those, 9,814 were cases ≥15 years or older with information on homeless status. Of those cases, 565 were reported as being homeless.
Other facts about TB in the homeless population include:

A person without a fixed, regular, adequate nighttime residence within the 12 months preceding the TB diagnostic evaluation is reported as homeless
The majority of persons with TB who report being homeless are U.S.-born: 20% are foreign born.
Since 1993, the total number of TB cases among the homeless population has decreased by over 50%; however, in the same time period, the percent of persons with TB who are homeless has only decreased from 7.5% to 5.8%.

Chart 2: This graph shows the number of TB cases reported to be homeless within 12 months prior to their TB diagnosis from 1993 through 2011. Cases must have been above 14 years of age. The number of homeless cases has decreased from a high of 1379 cases in 1994 to 565 in 2011 and parallels the overall decline in cases during this time. This category has seen a continuous decrease in cases since 1994; the years 2003, 2006, and 2010 have been exceptions with a small increase in cases. Of total cases, 6.8% were homeless in 1994 and percentages have ranged between 7.5% in 1993 and 5.4% in 2009. Since 2009 there has been a small increase in 2010 (5.7%) and in 2011 (5.8%).
To address TB among homeless persons, CDC is collaborating with other national and public health organizations to improve screening, diagnosis, and treatment of homeless persons and improve TB control activities in partnership with healthcare agencies addressing the needs of persons experiencing homelessness. Although TB cases among the homeless population are declining in number, the homeless population still represents an important risk group among U.S.-born TB patients.

In some states, over 10% of TB cases were among homeless persons in 2011; the highest percent reported by a jurisdiction was 23% (14 of their 60 TB cases with known status were reported as homeless).

To achieve TB elimination, ongoing efforts are needed to address the disproportionate number of TB cases among this high-risk population.