Comparative value of active and passive surveillance over time in treated leprosy patients, in the prevention of further disability.

Editor, Van Brakel et aI. have recently made a strong case for using the EHF score (Eye-Hand-Foot score) as a means of monitoring changes in impairment status in individuais or groups of people over time. lt would provide at least a crude measure of the effectiveness of prevention of impairment activities . ! It is a simple score, the components of which are already collected in most leprosy control programmes. At ALERT, the WHO lmpairment Grades have been recorded for each eye, hand and foot at regular intervals for all patients on treatment and the EHF score can therefore be calculated by summation for each patient at various points after diagnosis. Some preliminary results of using the EHF score over time were reported at the lnternational Leprosy Congress in Beijing and we would like to point out some of the most relevant findings. Many leprosy control programmes, including ALERT, have previously had a policy of active surveillance after release from treatment (RFT) in order to detect possible relapses as early as possible. Patients were given an annual appointment for review and were actively sought if they failed to attend. With multiple drug treatment (MDT), relapses have been extremely rare, so it is no longer deemed cost-effective to have active follow-up. Patients are now advised to report back to the health unit each year, or at any time if they develop any health problem, especially any sign of recurrence or worsening of their leprosy. This is termed passive surveillance and no action is taken if the patients do not attend. A disadvantage of the change from active to passive surveillance is that the opportunity for early detection of reactions and neuritis (especially silent neuritis) is lessened and this may become more important with shorter treatrnent courses. At ALERT, a cohort of patients in an MDT evaluation study is being followed up actively, while all others are followed passively. This situation gave us the opportunity to assess whether active surveillance of patients after RFT prevents further disability, as compared with passive surveillance.