Occupational Medicine (Oxford Journals). Vol. 63, Iss. 7, October 2013
Occupational screening of health care workers for tuberculosis infection: tuberculin skin testing or interferon-γ release assays?
Riassunto
Extract While incidence rates of tuberculosis (TB) have steadily declined in high-income countries, TB incidence continues to be high in many low-income countries. In general, TB disease and infection rates among health care workers (HCWs) are higher than that in the general population, although this differential is likely to be small in countries where TB incidence has now dropped to very low levels (e.g. North America). Despite the current low rates of TB in countries such as the USA and Canada, occupational health programmes continue to screen large numbers of HCWs, at recruitment and annually. In contrast, most high-TB-burden countries do not routinely screen HCWs, and TB rates in HCWs remain exceptionally high because of inadequate TB infection control. Until recently, occupational health programmes had no choice but to rely on the conventional tuberculin skin test (TST) for HCW screening. The TST has variable specificity and can be affected by Bacillus Calmette–Guérin (BCG) vaccination, especially when the vaccine is given after infancy or given multiple times. It is subjective and needs to be read carefully and interpreted with risk factor data. When repeated, interpretation of boosting, conversions and reversions can pose challenges. To overcome the problem of boosting, a baseline two-step TST is helpful. To avoid confusing nonspecific changes with real conversions, TST conversions are defined as a change from negative to…
Articoli correlati che potrebbero interessarti
Journal of Occupational and Environmental Hygiene. Vol. 12, Iss. 10, October 2015
Journal of Occupational and Environmental Hygiene. Vol. 12, Iss. 9, September 2015