US: Source patients in TB outbreaks have shared risk factors
Researchers have found shared risk factors among patients at the root of 26 tuberculosis (TB) outbreaks in the United States from 2002 to 2011.
Maryam Haddad, MSN, MPH, an epidemiologist with the Centers for Disease Control and Prevention in Atlanta, Georgia, and colleagues reviewed investigation reports by Centers for Disease Control and Prevention staff and found that most source patients reported substance abuse, half had been incarcerated at some point, and nearly half were homeless in the year before diagnosis.
The source patients were mostly men born in the United States who had infectious periods lasting 10 months or longer. Long infections are a concern because TB can spread and can be fatal if not diagnosed and treated.
These findings appear in the March 2015 issue of Emerging Infectious Diseases.
Most TB cases do not start outbreaks, the authors note. Ideally, if a person is diagnosed with infectious TB, an investigation will identify and treat contacts before the infection advances.
However, when outbreaks do occur, the results can severely strain health system resources. Most cases came to public health attention because the patient sought out treatment for TB instead of being found through contact investigations. When they sought care, 58% of patients experienced delay in getting a diagnosis.
The authors say this review highlights the need for fast and thorough investigations for TB cases in which patients have experienced substance abuse, incarceration, or homelessness.
The study may also raise awareness of TB among healthcare providers as the frequency of cases declines. More cases of pulmonary TB are being diagnosed in later disease stages, and the authors say that may be a consequence of providers having less familiarity with treating it.
"Public health departments should work with local health care providers to address barriers to accessing care faced by marginalized populations and in recognizing and diagnosing TB once symptomatic patients seek medical attention," the authors conclude.
The authors have disclosed no relevant financial relationships.
Emerg Infect Dis. 2015;21. Full text
Source:
Medscape
