According to a new report published by the Centers for Disease Control and Prevention (CDC), the number of tuberculosis (TB) cases in the United States has shown a continuous decline; however, the rate of decline remains inadequate in the context of meeting goals of elimination of TB by 2100.
Health departments from all 50 states reported data on verified TB cases, including each patient’s birth country, racial and ethnic background, HIV status, drug-susceptibility results, and risk factors.
Overall TB rates were calculated based on population estimates from the US Census Bureau; TB rates based on country of origin were based on population denominators from the US Census Bureau’s Current Population Survey.
The data revealed 9093 new cases of TB during 2017, or 2.8 per 100,000 individuals, a case count of 1.8% lower and a rate of 2.5% lower than in the previous year. Individuals living in congregate settings and/or from countries with high prevalence of the disease were identified as populations vulnerable to TB infection.
To eliminate TB by 2100, defined as <1 case per 1,000,000, the CDC aims for an annual percentage decline in rate of 3.9%; however, the United States still remains at 2.0%. Because reactivation of latent TB infection has been identified as the main cause of TB in the United States (>80% of cases), the US Preventive Services Task Force has recommended screening for latent TB infection; the CDC also recommends treatment.
Limitations of this analysis include its reliance on provisional reports; finalized data are not yet available. Furthermore, only estimates of population were available for calculation of case rates.
“Control of active TB and a major effort to decrease latent TB infection are both necessary to reduce morbidity and achieve TB elimination in the United States,” the report stated. “An important component of this strategy is the testing and treatment of populations most at risk for latent TB infection, persons born in countries with high TB prevalence, and persons in high-risk congregate settings.”
Stewart RJ, Tsang CA, Pratt RH, Price SF, Langer AJ. Tuberculosis — United States, 2017. MMWR Morb Mortal Wkly Rep. 2018;67:317-323.