Screening for tuberculosis: the port of arrival scheme compared with screening in general practice and the homeless.

BACKGROUND: Tuberculosis is increasing in London, especially in those recently entering the UK from an area of high incidence. Screening through the port of arrival scheme has a poor yield and has been considered discriminatory.
METHODS: A study was undertaken to compare the yield and costs of screening new entrants in a hospital based new entrants' clinic (1262 referrals from the port of arrival), general practice (1311 new registrations), and centres for the homeless (267 individuals) using a symptom questionnaire and tuberculin testing if indicated. Clinical outcome measures were cases of tuberculosis, tuberculin reactors requiring chemoprophylaxis and BCG vaccinations. Cost outcomes were cost per individual screened and cost per individual per case of tuberculosis prevented.
RESULTS: Verbal screening limited tuberculin testing to 16% of those in general practice; most were tested at the other two locations. Intervention (BCG vaccination, chemoprophylaxis or treatment) occurred in 27% of those who received tuberculin testing. Attendance for screening was 17% of the port of arrival notifications (63% had registered with a GP), 54% in primary care, and 67% in the homeless (42% registered with a GP). Costs for screening an individual in general practice, hostels for the homeless, and the new entrants' clinic were 1.26 pounds sterling, 13.17 pounds sterling and 96.36 pounds sterling, respectively, while the cost per person screened per case of tuberculosis prevented was 6.32 pounds sterling, 23.00 pounds sterling, and 10.00 pounds sterling, respectively. The benefit of screening was highly sensitive to the number of cases of tuberculosis identified and case holding during treatment.
CONCLUSION: Screening for tuberculosis in primary care is feasible and could replace hospital screening of new arrivals for those registered with a GP.