By: Kelly D. Ogle, BSDH, MIOP, CMPM, CHOP®
Director of OSHA and HIPAA Services
Mycobacterium tuberculosis is a pathogenic microorganism that causes respiratory (and other) infections in humans and other animals. It is the causative agent of the illness commonly called “TB.”
- tuberculosis is airborne and is generally classified as a respiratory pathogen, although it can certainly spread to other parts of the body, such as the brain. The bacterium is an acid-fast bacillus that is carried through the air in very small (1—5 microns) infectious particles called droplet nuclei. These droplet nuclei may be released when a person with pulmonary or laryngeal TB disease coughs, sneezes, shouts or sings. If these are inhaled by a susceptible individual, that individual may become infected, although most people will not develop symptoms. The most likely transmissions are from patients with active disease who have not been treated with an effective antibiotic or who have not been placed in respiratory isolation.
Of those exposed individuals who develop latent infections but are not treated, only 5-10% will later develop clinical illness. Latent infection means that the individual has a positive skin test and their chest x-ray is negative. Clinical disease includes symptoms.
Symptoms of TB infection include—
- Active coughing for more than three weeks
- Coughing up blood
- Unexplained weight loss
- Loss of appetite
- Night sweats
- Chest pain
Screening tests for TB should be done for individuals who have spent time with an active TB patient, those who are from areas where TB is common, and for people who work in high-risk settings (correctional facilities, long-term care facilities, nursing homes, and homeless shelters).
A TB skin test or a TB blood test can tell if an individual has been infected with TB, but it cannot differentiate between latent TB infection and TB disease. Other tests, such as a chest x-ray and/or a sputum sample for smear and culture, are needed to find out if the person has active disease. Latent TB infection (LTBI) means that the individual has a positive skin test but no symptoms; they cannot transmit the infection to others. TB disease is the condition caused by mycobacteria and includes symptoms. Individuals with active disease can transmit their infection to others. Although the disease is found primarily in the lungs, it can also be found in other parts of the body, although this is rare.
A total of 9,557 TB cases (a rate of 3.0 cases per 100,000 persons) were reported in the United States in 2015. The overall number of TB cases in the United States in 2015 increased over the previous year after having declined yearly from 1993–2014. Despite a slight increase in case count, the TB incidence rate per 100,000 persons has remained relatively stable at approximately 3.0 since 2013.
OSHA does not have a standard to protect employees from exposure to M. tuberculosis, but they rely on compliance directives and their Respiratory Protection Standard. In healthcare settings, OSHA will inspect for occupational exposure to TB in the following circumstances:
- In response to a valid employee complaint about TB exposure or a valid referral from another governmental or safety and health professional.
- In response to TB-related employee fatalities or catastrophes.
- As a part of all health inspections in facilities where the number of TB infections among patients or clients is greater than the incidence of TB infections in the general population.
Outpatient settings include TB treatment facilities, medical or dental offices, ambulatory care, and dialysis units. Nontraditional settings may include drug treatment centers, emergency medical services and homeless shelters.
OSHA released a new compliance directive mid-2015 that supersedes CPL 02-00-106, Enforcement Procedures and Scheduling for Occupational Exposure to Tuberculosis. The new instruction, CPL 02-02-078, bears the same title but has several significant changes based on guidance from the Centers for Disease Control and prevention (CDC): Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in Health-Care Settings, 2005, MMWR December 30, 2005/Vol. 54/No / RR-17. This is the document that has been used to develop the Tuberculosis chapter in the DoctorsManagement OSHA Manual every year since 2006.
- Additional environments are now considered TB healthcare settings, including settings in which emergency care services are provided and in laboratories handling clinical specimens that may contain “TB.”
- Term “tuberculin skin test” (TST) replaces “purified protein derivative test.”
- The newer screening method, the blood test for M. tuberculosis, is added.
- Risk classifications for healthcare settings are used; these include low, medium and potential ongoing transmission.
- Less frequent TB screening is recommended for some workers.
METHODS OF COMPLIANCE
- A written TB Infection Control Plan to include—
- Early identification of individuals with suspected or confirmed TB.
- Annual review and update.
- Supervision by someone with the proper expertise in infection control.
- TB Risk Assessment that should be—
- Initial and ongoing.
- Regardless of whether patients with suspected or confirmed TB disease are expected to be encountered in the setting.
- Used to determine the risk classification of low risk, medium risk, or potential ongoing transmission (potential ongoing transmission applies to any setting with evidence suggestive of person-to-person transmission of M. tuberculosis in the past year).
- The administrative, environmental, and respiratory protection controls and the need for medical surveillance will depend on the risk category.
- Medical Surveillance
TB screening should be for workers who—
- Enter patient or treatment rooms used for suspected or confirmed cases.
- Participate in cough-inducing or aerosol-generating procedures (aerosolized medica-tion administration, bronchoscopy, or sputum inducement).
- Process specimens for TB testing.
- Install, maintain or replace environmental controls in areas where TB patients might be located.
Two-step testing is preferred for initial skin testing for any employee who has not had a documented negative test in the past 12 months. This means that if the first test is negative, a second test should be done to test of possible boosting from a past infection. In low-risk settings, annual screening is not needed. In medium-risk settings, screening should be done annually. In settings with potential ongoing transmission, screening should be done every 8-10 weeks until the risk classification is lowered to medium risk.