I. INTRODUCTION
In response to the problems encountered by many health systems in providing directly observed therapy (DOT) for TB, New International Standards no longer insist on DOT for all patients but state "Practitioner must not only prescribe an appropriate regimen, but also be capable of assessing the adherence of the patient to the regimen and addressing poor adherence when it occurs". (Tuberculosis Coalition for Technical Assistance 2006) Furthermore, the world health organization (WHO) now recommends that all patients have a treatment supporter acceptable to the patient who is trained and supervised by health services. (WHO 2006) The supporter may or may not give DOT. Unfortunately, these recommendations fail to overcome a dilemma that has plagued TB control efforts for half a century, namely the lack of a practical and accurate means of determining who is adherent. This paper describes a neglected and emerging technology that needs to be tried and evaluated as a means to overcome this quandary, improve the effectiveness of the treatment supporter, and achieve more successful treatment outcomes.
II. THE SUCCESS AND PROBLEMS WITH DOT
In 1994 WHO launched a five-component program called the DOTS strategy (WHO 1994) that included DOT for all patients at least in the initial phase of treatment, to overcome serious deficiencies in earlier programs based largely on self-administered treatment (SAT). (Raviglione and Pio 2002) The 1994 WHO recommendation has been accompanied with improved successful treatment rates that averaged 86% in 2004. (WHO 2007). 1 Success rates were based on relatively lax criteria: 1) patients with a negative sputum smear at the end of therapy (cures), plus 2) patients who complete 6 months of treatment but no end of treatment sputum smears were obtained.
An excellent review of the multiple problems encountered by patients and health care delivery systems in implementing DOTS is available (Lienhardt and Ogden 2004) The review refers to the diversity of patients' attitudes towards the disease, the extreme variability of access to care, the costs incurred by the patients, the aggravation of stigma, the non use of direct observation for some patients in DOTS programs, the deselecting of patients deemed least likely to comply, and the use of additional interventions that may not be sustainable because they require external funding. Consequently, they questioned the appropriateness of DOT as a universal paradigm for TB control. Another group documented false reporting given by compassionate caregivers. (Pungrassami et al. 2002) They found that SAT was given when DOT was allegedly given: 11% of time for clinic DOT, 23% for community worker DOT, and 35% for family DOT.
However, full implementation of DOTS is very difficult, and programs without sufficient resources often fail to reach this modest goal. For instance, a carefully evaluated DOTS program in Tamul Nadu State, India only achieved 75% success at the end of treatment with 12% relapses by 18 months. (Thomas et al. 2005)