481—59.2(135B,135C) Definitions. For purposes of this chapter, the following definitions apply:
“Bacille Calmette-Guérin vaccination” or “BCG vaccination” means a vaccine for TB. BCG vaccination is used in many countries with a high prevalence of TB to prevent childhood tuberculosis meningitis and miliary disease. BCG vaccination is not generally recommended for use in the United States because of the low risk of infection with Mycobacterium tuberculosis, the variable effectiveness of the vaccine against adult pulmonary TB, and the vaccine’s potential interference with tuberculin skin test reactivity.
“Baseline TB screening” means the screening of health care workers (HCWs) of health care facilities or hospitals at the beginning of employment in a facility or hospital and of residents of health care facilities upon admission to a facility for latent tuberculosis infection (LTBI) and TB disease. Baseline TB screening includes a symptom screen for all HCWs and residents, and two-step tuberculin skin test (two-step TST) or single interferon-gamma release assay (IGRA) for M. tuberculosis for those persons with previous negative test results for M. tuberculosis infection.
“Baseline TST” or “baseline IGRA” means the two-step TST or IGRA, respectively, which is administered at the beginning of employment to newly hired HCWs or upon admission of residents to health care facilities.
“Boosting” means a phenomenon in which a person has a negative TST (i.e., false-negative) result years after infection with M. tuberculosis and then a positive subsequent TST result. The positive TST result is caused by a boosted immune response of previous sensitivity rather than by a new infection (false-positive TST conversion). Two-step testing reduces the likelihood of mistaking a boosted reaction for a new infection.
“Department” means the department of inspections and appeals.
“Employment” or “employed” means to be hired or retained for paid or unpaid work in a facility or hospital.
“Extrapulmonary TB” means TB disease in any part of the body other than the lungs (e.g., kidney, spine, or lymph nodes).
“Health care facility” or “facility” means a health care facility as defined in Iowa Code section 135C.1 or a long-term care service of a hospital as defined in rule 481—51.38(135B).
“Health care worker” or “HCW” means any paid or unpaid person (including health care students) working in a health care facility or hospital, including any person who is paid either by the health care facility or hospital or paid by any other entity (i.e., temporary agency, private duty, Medicaid/Medicare or independent contractors), or any volunteer who volunteers in a health care facility or hospital on a consistent and regularly scheduled basis for five or more hours per week. Specifically excluded from the definition of “health care worker” are individuals such as visitors, building contractors, repair workers or others who are in the facility or hospital for a very limited purpose and are not in the facility or hospital on a regular basis.
“Hospital” means a hospital as defined in Iowa Code section 135B.1.
“Interferon-gamma release assay” or “IGRA” means a whole-blood test that can aid in diagnosing M. tuberculosis infection.
“Laryngeal TB” means a form of TB disease that involves the larynx and may be highly infectious.
“Latent TB infection” or “LTBI” means infection with M. tuberculosis without symptoms or signs of disease having manifested.
“Mantoux method” means a skin test performed by intradermally injecting 0.1 mL of purified protein derivative (PPD) tuberculin solution into the volar or dorsal surface of the forearm.
“Patient” means a person admitted to a hospital.
“Pulmonary TB” means TB disease that occurs in the lung parenchyma, usually producing a cough that lasts greater than three weeks. Pulmonary TB is usually infectious.
“Purified protein derivative tuberculin” or “PPD tuberculin” means a material used in diagnostic tests for detecting infection with M. tuberculosis.
“Resident” means a person admitted to a health care facility or a long-term care service of a hospital as defined in rule 481—51.38(135B). For purposes of this chapter, “resident” does not include a patient admitted to a hospital.
“Risk classification” means the category that the infection control team, or designated other staff, determines is appropriate for the facility or hospital as a result of the TB risk assessment.
“Serial TB screening” means TB screening performed at regular intervals following baseline TB screening. Serial TB screening, also called annual or ongoing TB testing, consists of two components: (1) assessing for current symptoms of active TB disease, and (2) testing for the presence of infection with M. tuberculosis by administering either a TST or single IGRA.
“Symptom screen” means a procedure used during a clinical evaluation in which persons are asked if they have experienced any departure from normal in function, appearance, or sensation related to TB disease (e.g., cough).
“TB patient” means a person who had undiagnosed infectious pulmonary or laryngeal TB while in a health care facility or hospital during the preceding year. “TB patient” does not include persons with LTBI (treated or untreated), extrapulmonary TB disease, pulmonary TB, or laryngeal TB who have met criteria for noninfectiousness.
“TB risk assessment” means an initial and ongoing annual evaluation of the risk for transmission of M. tuberculosis in a particular health care setting.
“TB screening” means an administrative control measure in which evaluation for LTBI and TB disease is performed through baseline and serial screening of HCWs in hospitals and health care facilities and residents of health care facilities.
“Transfer” means an HCW changes employment from one health care facility or hospital to another health care facility or hospital where the time frame between employment does not exceed 90 days.
“Treatment for LTBI” means treatment that prevents the progression of M. tuberculosis infection into TB disease.
“Tuberculin skin test” or “TST” means a diagnostic aid for finding M. tuberculosis infection. The Mantoux method is the recommended method to be used for TST.
“Tuberculosis” or “TB” means the namesake member organism of M. tuberculosis complex and the most common causative infectious agent of TB disease in humans. In certain instances, the species name refers to the entire M. tuberculosis complex, which includes M. bovis, M. african, M. microti, M. canetti, M. caprae, and M. pinnipedii.
“Tuberculosis disease” or “TB disease” means a condition caused by infection with a member of the M. tuberculosis complex that has progressed to causing clinical (manifesting signs or symptoms) or subclinical (early stage of disease in which signs or symptoms are not present, but other indications of disease activity are present) illness.
“Two-step tuberculin skin test” or “two-step TST” means the procedure used for the baseline skin testing of persons who may receive serial TSTs.
[ARC 3930C, IAB 8/1/18, effective 9/5/18]