Modified Active Surveillance System (MASS); a novel clinicopathological evaluation of PB leprosy patients after RFT, in Mangalore, India.

The current recommendations for leprosy control programmes include stopping active surveillance in view of the very low relapse rates and a phased integration of leprosy services with the general health services. Passive surveillance may not be adequate, more so because of the introduction of newer, shorter drug regimens. This study is an effort to evolve a modified active surveillance, which is cost-effective, simple and also a novel substitute for the increased workload caused by the dwindling number of PMWS. One thousand one hundred RFT-PB leprosy patients were recalled for a review under the Modified Active Surveillance System (MASS), carried out over two phases. Patients were divided into groups as per the mode of response to the mailed postcards; Responders (patients who reported to the OPD in person), Untraceables (patients whose postcards returned back) and non-responders (patients who did not report of the OPD after receiving the mail). At the end of phase I, we had 120 Responders, 480 Untraceables and 500 Non-responders. In phase II, which began 2 months later, the 500 non-responders were dispatched reminders. In this phase, there were 31 responders, 60 untraceables and 409 non-responders. Thus, at the completion of phases I and II, there were 151 responders, 540 untraceables and 409 non-responders. Of the 151 patients examined, 71 had no complaints (category 1), 41 had fresh leprosy-related complaints (category IIA), 14 had fresh leprosy-unrelated complaints (category IIB) and 25 had persistence of old complaints (category III). Cumulative PYR of the 151 patients was 1155.42. Forty-one patients had fresh leprosy-related complaints. Skin biopsy was done in the 17 patients with fresh skin patches, of whom four showed histopathological evidence of relapse. Relapse rate in our study was 0.35/100 PYR. Mean duration after RFT at relapse was 4.9 years. Our scepticism towards passive surveillance systems is justified by these 41 patients with fresh leprosy-related complaints, who voluntarily reported only after receiving the postcards. We recommend the introduction of a phase III, wherein the services of PMWs may be used to contact the 409 patients who remained unresponsive at the completion of phases I and II. We also recommend the introduction of a universal format for recording addresses of all new patients, which would be of immense help in patient retrieval in all such surveillance systems in the future.

Development and standardization of a piezo electric immunobiosensor for foot and mouth disease virus typing.

An immunobiosensor using a piezo electric (PZ) crystal was developed and standardized for foot and mouth disease (FMD) diagnosis and virus typing. A 6MHz quartz crystal was used as the frequency determining element. Foot and mouth disease virus (FMDV) type specific antibody raised in rabbits/monoclonal antibody was coated on the crystal surface and the resonance measured. One microlitre of the 10% aqueous suspension of the clinical sample (tongue or foot epithelium) was applied on both surfaces of the crystal and the resonance recorded. A difference in resonance of more than -2.5Hz was obtained in positive samples (homologous antigen and antibody). The test was standardized initially using various dilutions of FMD tissue culture antigen. Repeatability and sensitivity were also tested and it was found that the crystals could be washed and reused eight times. The test could be used for FMDV type specifically and no cross-reaction between FMDV types was observed. The shelf-life of the antibody-coated crystal stored at room temperature was 18 weeks. Application of the biosensor test to the FMDV clinical samples confirmed virus typing results when compared with enzyme-linked immunoabsorbent assay (ELISA) and it could also detect virus in ELISA negative samples and mixed virus infections.