摘要：Objectives. We determined the prevalence and treatment rates of latent tuberculosis infection (LTBI) in newly arrived refugees in San Diego County, California, and assessed demographic and clinical characteristics associated with these outcomes. Methods. We analyzed data from LTBI screening results of 4280 refugees resettled in San Diego County between January 2010 and October 2012. Using multivariate logistic regression, we calculated the associations between demographic and clinical risk factors and the outcomes of LTBI diagnosis and LTBI treatment initiation. Results. The prevalence of LTBI was highest among refugees from sub-Saharan Africa (43%) and was associated with current smoking and having a clinical comorbidity that increases the risk for active tuberculosis. Although refugees from sub-Saharan Africa had the highest prevalence of infection, they were significantly less likely to initiate treatment than refugees from the Middle East. Refugees with postsecondary education were significantly more likely to initiate LTBI treatment. Conclusions. Public health strategies are needed to increase treatment rates among high-risk refugees with LTBI. Particular attention is required among refugees from sub-Saharan Africa and those with less education. Tuberculosis (TB) in the United States is primarily a disease of foreign-born people. In 2011, approximately 62% of all incident TB cases within the United States occurred among foreign-born individuals, a proportion that has been increasing steadily since 2001. 1–3 Within the first few years after arrival in the United States, immigrants and refugees from countries in which TB is highly endemic have been found to develop active TB at rates more similar to incidence rates in their home countries than those of the United States, which has been documented to be largely because of reactivation of latent TB infection (LTBI) acquired abroad. 4–8 Among foreign-born people in the United States, the risk for active TB is particularly elevated for immigrants and refugees from sub-Saharan Africa and Southeast Asia. 2,3 A recent study found that the TB case rate among Africans in the United States was 3 times higher than that among other foreign-born people and 27 times higher than that among US-born people, a finding attributed to the large burden of LTBI in this population. 9 Refugees resettling in the United States have typically originated from regions with high rates of active TB, including Southeast Asia and sub-Saharan Africa. In addition, previous studies have documented that refugees have higher rates of TB after resettlement in the United States than other foreign-born people. 10,11 Although active TB disease among refugees is usually diagnosed and treated before departure for the United States, 12 the treatment of LTBI before arrival in the United States is not mandated. To prevent the reactivation of LTBI after arrival to the United States, the Centers for Disease Control and Prevention currently recommends screening for and treating LTBI among all recently arrived refugees. 8,13 Despite the Centers for Disease Control and Prevention’s recommendation, there has been only limited assessment of the prevalence, epidemiology, and treatment rates of LTBI among newly arrived refugees in the United States. Previous studies of LTBI among refugees in the United States 14–17 were primarily conducted during the previous decade and do not reflect changes in the demographics of more recent refugee arrivals. Additionally, few reported LTBI treatment completion rates. The majority of these studies were also conducted before the introduction of interferon γ release assays, TB screening tests that provide a more accurate diagnosis of LTBI because of their higher specificity than the tuberculin skin test. 18,19 Between 2010 and 2012, California received almost 10% of the 187 966 refugees settled in the United States, making it one of the largest resettlement regions in the country. 20–22 San Diego County, in Southern California, is a leading refugee resettlement site, and it also has one of the highest rates of active TB in the country, with an incidence rate of 8.4 cases per 100 000 people in 2011. 23,24 Assessment of LTBI prevalence and treatment among recently arrived refugees is needed to effectively address the control of TB, because untreated, reactivated LTBI in this population may be an important contributor to TB incidence in the United States. 8 This information is critical for public health departments that provide care for refugee populations, not only to ensure the health of individual refugees, but also to prioritize efforts to reduce the disproportionately high rate of active TB among foreign-born people in the United States. In this study, we investigated LTBI prevalence by birth region and clinical risk factors, and identified demographic and clinical factors associated with LTBI treatment initiation and completion among newly arrived refugees diagnosed with LTBI in San Diego County from January 1, 2010, through October 1, 2012.
