According to the Centers for Disease Control and prevention (CDC), there were 13,293 reported cases of
tuberculosis in 2007, a decline by 4.2% compared to 2006. Overall, the TB incidence rate has decreased from 7.3%, as seen in the 1990s, to 3.8% during the first seven years of this decade. However, this rate of decline appears to be slowing, and the ultimate goal of eliminating TB in the US is still elusive. Slightly more than one per cent (1.1%) of those patients with TB has multidrug-resistant tuberculosis (MDR TB). In 2008, the World Health Organization (WHO) reported that MDR TB was at the highest rate ever.
While tuberculosis is still relatively rare in this country, it is a large health issue among at-risk groups. The rate is almost ten times higher in foreign-born persons living in the US as opposed to US-born individuals. Among those TB-positive patients in 2007 who were also tested for HIV, 11.3% were HIV-positive. HIV is now recognized as a key risk factor in the progression from latent to full TB infection; thus the CDC has recommended HIV testing for all TB patients.
Current guidelines call for targeted screening among such groups. Adults who are part of or have been exposed to those who fall into high risk groups should also be considered for screening.
The infection may be detected via a tuberculin skin test and/or a blood test. The CDC notes that more data are needed on the blood test’s effectiveness in children and those with HIV or acquired immunodeficiency syndrome (AIDS). Although the CDC discourages routine screening of low-risk populations, students are often required to be tested before the first day of school, most health care workers are routinely tested for possible exposure, persons who have had contact with an individual who has suspected or confirmed TB, and persons with or at risk for HIV infection are the CDC’s highest screening priority.
If an adult has been exposed to a high-risk adult, he or she should be tested. The American Academy of Family Physicians’ high-risk category includes the following:
- Those with close contact to a person with known or suspected TB
- Health care workers
- Immigrants from countries with a high rate of this disease (generally, less industrialized, developing nations)
- People with HIV
- Alcoholics
- Users of injection drugs or other illicit substances
- Residents of long-term care facilities (such as nursing homes, mental health facilities, prisons, AIDS care facilities, and homeless shelters)
- Those considered medically underserved from a low-income environment
Others vulnerable to infection:
- The elderly and individuals whose immune systems are impaired, including persons whose medical conditions or therapies put them at greater risk.
- Persons who live in unclean or crowded places and those without healthy food.
- Infants, children, and adolescents: if they are exposed to high-risk adults, they should be tested.
Links
Centers for Disease Control and Prevention: TB Fact sheet
Sources
US Centers for Disease Control and Prevention. QuantiFERON-TB Gold Test (fact sheet). Last modified 16 Nov 2007. Available on the Internet at http://www.cdc.gov/tb/pubs/tbfactsheets/QFT.htm through http://www.cdc.gov. Accessed 6 Dec 2007.
US Centers for Disease Control and Prevention. Trends in Tuberculosis – United States, 2007. Available on the Internet at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5711a2.htm through http://www.cdc.gov.
New Jersey Medical School and National Tuberculosis Center, University of Medicine and Dentistry of New Jersey. History of TB: the recent TB epidemic. 26 Feb 2001. Available on the Internet at http://www.umdnj.edu/globaltb/tbhistory.htm through http://www.umdnj.edu. Accessed 26 Jul 2004 and 6 Dec 2007.
D’Alessandro D and Huth L. Children’s Virtual Hospital and The University of Iowa. Pediatrics common questions, quick answers: TB (tuberculosis). Last revised Apr 2002. Available on the Internet at http://lib.cpums.edu.cn/jiepou/tupu/atlas/www.vh.org/pediatric/patient/pediatrics/cqqa/tb.html through http://lib.cpums.edu.cn. Accessed 26 Jul 2004 and 6 Dec 2007.
Screening for tuberculosis and tuberculosis infection in high-risk populations: recommendations of the advisory council for the elimination of tuberculosis. 8 Sep 1995. MMWR 44(RR11);18-34. Available on the Internet at http://www.cdc.gov/mmwr/preview/mmwrhtml/00038873.htm through http://www.cdc.gov. Accessed 21 Jul 2004 and 28 Jan 2008.
Targeted tuberculin testing and treatment of latent tuberculosis infection (American Thoracic Society/CDC statement). 9 Jun 2000. US Centers for Disease Control and Prevention. MMWR 49(RR06);1-54. Available on the Internet at http://www.cdc.gov/mmwr/preview/mmwrhtml/rr4906a1.htm through http://www.cdc.gov. Accessed 21 Jul 2004 and 6 Dec 2007.
University of Iowa Health Care. Tuberculosis. Last modified 19 Oct 2006. Available on the Internet at http://
www.uihealthcare.com/topics/infectiousdiseases/infe4731.html through http://
www.uihealthcare.com. Last accessed 6 Dec 2007.
Tuberculosis. In: Caring for Your Baby and Young Child: Birth to Age 5. 1999. Bantam. Excerpt on the Internet at http://www.medem.com/medlb/article_detaillb.cfm?article_ID=ZZZ1BN54FDC&sub_cat=573 through http://www.medem.com. Accessed 26 Jul 2004 and 6 Dec 2007.
