Introduction to health care workers tb test
Health-care Workers fall under high risk group to Tuberculosis (TB), due to their occupational exposure to infectious diseases. So it becomes essential to conduct testing of Health-Care Workers for TB infection.
The CDC (Centers for Disease Control and Prevention) and NTCA (National Tuberculosis Controllers Association) have created updated guidelines regarding TB screening and testing in Healthcare setups in 2019. These guidelines provide structural framework for the screening, testing, frequency of testing and preventive treatment for health care workers.
How Often And When Should The Health-Care Workers Be Tested?
The updated guidelines made the following changes in terms of screening and testing:
- Decrease in frequency of TB screening for the Health-Care Workers in various settings. Change in criteria of screening frequency changed.
- Clear testing criteria of the health care professionals.
Guidelines for the frequency of testing and criteria of the testing of TB in Healthcare setting:
- Baseline testing of health professional required. Annual additional tests are not performed if the exposure to the infection is null.
- Interferon Gamma Release Assay (IGRA) or Tuberculin Skin Test (TST) with confirmed exposure to TB and who have no prior documented TB infection or Latent TB Infection (LTBI),
- In personnel with newly positive test result, symptom evaluation and chest radiography with followup as indicated,
- Unless contraindicated, personnel with untreated Latent TB Infection encouraged to undergo treatment,
- Annual symptom based screening for individuals with untreated LTBI,
- The health professionals are provided with annual education on TB.
What Is TB Risk Assessment And How It Affects TB Screening Process In Health- Care Setups?
Risk Assessment is evaluation process to see the risk of transmission of Mycobacterum tuberculosis in a setting. The testing should be done even when there is no recent exposure to TB. Risk assessment is essential to check the status of a health setup and proper occupational health measures.
Risk Assessment helps in effective prevention of the spread. It checks the need of improvement in the strategies to adopt Administrative, Environmental and Respiratory Protection Control required for a health care settings.
TB Screening According To Risk Assessment:
Risk Assessment classifies screening into three groups:
- Low Risk Setup : Conduct a baseline screening test when hiring the individual. In such setup, annual screening is not necessary.
- Medium Risk Setup : Conduct a baseline screening test when hiring the health professional . After baseline screening, the individuals need to be assessed annually by symptom screening or test for M. tuberculosis. Individuals with a baseline positive M. tuberculosis infection should receive one chest radiograph result to exclude TB disease.
- Screening for Health-Care Workers or settings classified as Potential Ongoing Transmission: Testing is performed in a gap of 8 to 10 weeks until the infection transmission seems to be under control and there is no apparent ongoing transmission in the setting.
The Potential Ongoing Transmission stage should be treated with urgency and prompt investigation and preventive measures should be taken. It is used as a secondary classification. Even when the disease is under control and no apparent transmission is seen, the hospital setting should be treated as Medium Risk for one year.
In classification of Low and Medium Risk settings, the setting is classified and treated as Medium Risk setup.
The Essentials of TB Infection Control:
Any health care setting needs a prompt plan of action to control the spread of TB infection through detection, precautions and treatment facilities. The control program is summarized into three categories:
- Administrative controls: It includes management to reduce risk of exposure to TB infected people. Administrative control measures include :conduction of a TB risk assessment of a setting, educating the health care workers on aspects like prevention and treatment of TB infection, use of epidemiological study methods for prevention, screening and testing of health care workers who are at a risk of infection, effective work practices for the management of patients.
- Environmental controls: The transmission of TB infection is usually through droplets of the infected person. In order to prevent transmission, reduction of infectious droplet is important. The use of general ventilation and HEPA ( High Efficiency Particulate Air) helps decrease the contaminated droplet concentration in air.
- Respiratory-Protection controls: The Administrative and Environmental approach deal with minimizing the exposure of the patient to the infection. Respiratory Protection control is used in situations of high exposure areas, like in Health care workers. In this control, training Health care workers on respiratory protection is done and respiratory hygiene is taught.