Concerning Tuberculosis Trends and Guidance to Identify and Eliminate Tuberculosis
Summary of Concerning Tuberculosis Trends in Nevada
- Nevada has reached a 10-year high in Tuberculosis (TB) disease cases.
- There has been a 40% increase in the TB disease incidence from 2022 to 2023.
- An extraordinary number of infectious TB disease contact investigations have occurred, involving TB testing and evaluation of hundreds of persons exposed to infectious TB in large-scale work and school settings in Nevada.
- TB disease incidence in non-U.S.-born persons has risen from 70% to 80% over the past 10 years.
- Birth outside of the United States remains the largest risk factor for TB disease in Nevada, as 80% of TB cases identified in 2023 were non-U.S.-born.1
To eliminate TB, Nevada’s public health systems in collaboration with health care providers need to increase identification of individuals at risk for TB, testing for TB infection, and provision of timely treatment for TB infection (latent TB infection, or LTBI).
Background
TB disease is spread by airborne transmission and remains a public health concern in the United States and Nevada. Nationally, more than 80% of TB disease cases develop from breakdown of longstanding LTBI. Identifying and testing individuals at risk for TB infection is recommended by the Centers for Disease Control and Prevention (CDC)2 and the U.S. Preventive Services Taskforce (USPSTF).3 Individuals at greater risk for TB include persons who were born in or traveled to areas where TB is common, including Asia, Africa and Latin America; persons who have spent time with someone who had TB disease; or persons who have lived in high-risk congregate settings, such as homeless shelters or correctional facilities.
Individuals at risk for TB infection should receive TB testing with an interferon gamma release assay (IGRA) blood test, and positive test results should be followed by a chest x-ray. Signs and symptoms of TB disease should also be evaluated. If active TB disease is ruled out, an individual with LTBI should be encouraged to take the offered short course LTBI treatment.
The CDC’s Think. Test. Treat TB website details the steps to effectively discuss TB infection as well as test and treat LTBI.4 Short course LTBI treatments are more favorably tolerated and successfully completed.5
Guidance for Health Care Providers
Individual TB Risk Assessment
- Health care providers should administer individual TB risk assessments to every patient and for each patient as new risk factors arise.
- The Nevada Tuberculosis Risk Assessment Tool can be found online here.
- The following are indicators of risk for TB infection or disease:
- Non-U.S.-born or travel > 1 month outside of the United States.Exposure ever to someone with TB disease.
TB testing with IGRA TB blood test (recommended over the skin test)
- Anyone answering “yes” to any of the TB risk factors should receive an IGRA TB blood test.
Chest x-ray following positive TB test result
- Normal/no evidence of TB disease results should be followed by LTBI treatment.
- Abnormal/suggestive of TB disease results must be recommended for airborne precautions and referred immediately to the local health department. Those who could have been exposed to an active TB case should be properly evaluated and tested for TB.
TB disease evaluation rule out and consultation
- Review symptoms indicating active TB infection: cough > 3 weeks, unexplained weight loss and loss of appetite, fevers of unknown origin, night sweats. Do not start LTBI treatment until TB disease is ruled out.
- Consult, educate and encourage LTBI short course treatments; give the patient language- appropriate educational materials, available at the CDC’s Think. Test. Treat TB website.
Short course LTBI treatment
- Health care providers should prescribe and manage LTBI treatment in the medical office. The CDC and Nevada TB Program encourage health care providers to manage LTBI treatment and not refer the patient to the public health department.
- Four-month Rifampin or 12-week/3-month once weekly Isoniazid & Rifapentine (3HP) is recommended.
Questions
For updated guidance, review the Division of Public and Behavioral Health Technical Bulletin web page regularly. Contact Susan McElhany, DMD, Tuberculosis Program, Office of State Epidemiology at smcelhany@health.nv.gov for other questions regarding TB risk assessment and TB prevention.
References
1 Nevada’s National Electronic Disease Surveillance System. 2014-2023 (accessed January 2024)