Extensive drug-resistant tuberculosis and health care workers

Article 4: Tuberculosis infection control in the working environment

Health care providers (HCPs) are at particularly high risk of infection with tuberculosis (TB) due to frequent exposure to patients with infectious diseases. In addition, undiagnosed, untreated and potentially contagious TB is often also seen in health facilities, increasing the exposure risk for HCPs and other staff. When HCPs themselves have HIV-associated immune-suppression they are at increased risk of developing active disease after exposure and the risk is especially increased in areas with undiagnosed TB.  The risk of HCPs for developing TB disease after exposure to drug-susceptible disease or drug-resistant disease is the same, as explained in the first paper of this series.

Even in settings with limited resources, health facilities can reduce the chances that TB will spread through: (1) personal protection measures for HCPs (discussed in the third paper of this series), (2) administrative controls and (3) environmental controls. It is important to recognise that the three infection control measures work in tandem; all three need to be comprehensively applied and if one is absent or inadequate, the other two will not be sufficient to alleviate the risk.

Administrative control measures have the greatest impact on preventing TB transmission within health facilities and they are the first priority in any setting regardless of resources. The goals of these are to prevent TB exposure of staff and patients and to reduce the spread of infection by ensuring rapid and recommended diagnostic investigation and treatment. This can best be accomplished through prompt recognition, separation and provision of services and referral of patients with potentially infectious TB disease. The critical components of administrative controls are: (1) an infection control plan for each facility, (2) training of staff and (3) an occupational health screening programme.

Each facility needs specific administrative controls, consisting of a multi-disciplinary infection control committee, an infection control team and an occupational health screening programme. The committee is responsible for drawing up the infection control plan, based on the South African Draft National Infection Prevention and Control Policy for TB, MDRTB and XDRTB (Department of Health, 2007). Dedicated staff is needed to ensure proper implementation and monitoring of the plan, which can only be effective if all staff understands the importance of these policies and their role in implementing them. Job-specific training should be given to all staff, whether they are directly involved with patient care (nursing-clinically), administrative staff or lay-workers. Training should be conducted before initial assignment and continuing education should be provided annually to all employees and volunteers. As part of the occupational health monitoring plan, all HCPs and staff in a facility, irrespective of risk of exposure or presence of TB signs and symptoms, need to be annually screened for TB disease. This should consist of chest radiography (picture 1), symptom screening and collection of a sputum specimen for microbiological investigation (picture 2). In addition, all staff need to have a general awareness of signs and symptoms, and if present, should approach the occupational health official for TB investigation.

Environmental control measures include ventilation (natural and artificial), air filtration and ultraviolet germicidal irradiation (UVGI) of the air in a room (Medical Research Council, 1999).  If patients are to provide sputum specimens for onsite diagnosis of TB, they should always do this in a well-ventilated booth or outside in the open air and away from other people, and not in small rooms such as toilets or enclosed areas.

The measures recommended in the policy documents (World Health Organization, 1999) should reduce the time persons who have been with undiagnosed TB spend in health facilities and should improve ventilation and thus dilution of any TB organisms in the environment. Nevertheless, the risk to HCPs and other staff will never be completely absent. Each person working in a high risk TB environment should have a high level of TB awareness. If signs or symptoms are present, seek early screening for TB, which should include tests for drug-resistance. Early initiation of appropriate treatment for TB, especially when drug-resistance is present, is key to ensure a good response to treatment, as described in the second paper of this series.

References
Department of Health (DOH) (2007) The draft National Infection Prevention and Control Policy for TB, MDRTB and XDRTB. [online] http://www.doh.gov.za/docs/policy/tb/part1.pdf (accessed on 31/05/2010)

Medical Research Council (MRC) (1999) Guidelines for the utilisation of ultraviolet germicidal irradiation (UVGI) technology in controlling transmission of tuberculosis in health care facilities in South Africa.  [online] http://www.sahealthinfo.org/tb/guidelines.pdf (accessed on 31/05/2010)

Migliori, GB. Loddenkemper, Blasi, RF. Raviglione, MC. (2007) 125 years after Robert Koch's discovery of the tubercle bacillus: the new XDR-TB threat. Is "science" enough to tackle the epidemic? European Respiratory Journal Vol 29 pp 423-427.

World Health Organization (WHO) (1999) Addendum to WHO Guidelines for the Prevention of Tuberculosis in Health Care Facilities in Resource-Limited Settings.  [online] http://whqlibdoc.who.int/hq/1999/WHO_TB_99.269_ADD_eng.pdf (accessed on 31/05/2010)

This article is also available in Afrikaans, Xhosa, Zulu, Sotho and Tsonga. Contact Joey Lancester at joey.lancester@mrc.ac.za or (012) 339-8561.

This article was developed and published in collaboration with the Tuberculosis Epidemiology and Intervention Research Unit and the Web and Media Technologies Platform of the South African Medical Research Council.

This series of publications has been made possible through a grant from the United States Department of Health and Human Services (HHS).