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Background Innovative approaches are required for leprosy control to reduce cases and curb transmission of Mycobacterium leprae. Early case detection, contact screening, and chemoprophylaxis are the most promising tools. We aimed to generate evidence on the feasibility of integrating contact tracing and administration of single-dose rifampicin (SDR) into routine leprosy control activities. Methods The leprosy post-exposure prophylaxis (LPEP) programme was an international, multicentre feasibility study implemented within the leprosy control programmes of Brazil, India, Indonesia, Myanmar, Nepal, Sri Lanka, and Tanzania. LPEP explored the feasibility of combining three key interventions: systematically tracing contacts of individuals newly diagnosed with leprosy; screening the traced contacts for leprosy; and administering SDR to eligible contacts. Outcomes were assessed in terms of number of contacts traced, screened, and SDR administration rates. Findings Between Jan 1, 2015, and Aug 1, 2019, LPEP enrolled 9170 index patients and listed 179 769 contacts, of whom 174782 (97·2%) were successfully traced and screened. Of those screened, 22 854 (13·1%) were excluded from SDR mainly because of health reasons and age. Among those excluded, 810 were confirmed as new patients (46 per 10 000 contacts screened). Among the eligible screened contacts, 1182 (0·7%) refused prophylactic treatment with SDR. Overall, SDR was administered to 151 928 (86·9%) screened contacts. No serious adverse events were reported. Interpretation Post-exposure prophyl

Ortlepp brittle shears can form in deep and highly stressed mines and have caused problems in gold mines in South Africa. Slip weakening behaviour and rupture propagation along Ortlepp brittle shear zones have been been studied in friction experiments carried out under dry conditions at slip velocities ranging from around 1 to 1200 mm/s. Tests were carried out with and without a fault gouge layer between the two sliding surfaces, using both natural fault gouge (from shear ruptures at the Cooke 4 mine in the Witwatersrand Basin) and artificial gouge. The results showed a strong difference in the frictional weakening behaviour, with a lower slip velocity (around 5 mm/s) and lower frictional strength where there was no fault gouge between the sliding rock surfaces. The existence of the fault gouge layer delayed the onset of fault weakening. It is thought that flash heating may be the main active weakening mechanism. It is concluded that the use of low, intermediate and high slip velocity friction experiments with and without an intervening fault gouge layer is suitable for modelling rupture propagation in underground shear zones to forecast the severity of possible rockbursts, and improve safety., Ortlepp brittle shears can form in deep and highly stressed mines and have caused problems in gold mines in South Africa. Slip weakening behaviour and rupture propagation along Ortlepp brittle shear zones have been been studied in friction experiments carried out under dry conditions at slip velocities ranging from around 1 to 1200 mm/s. Tests were carried out with and without a fault gouge layer between the two sliding surfaces, using both natural fault gouge (from shear ruptures at the Cooke 4 mine in the Witwatersrand Basin) and artificial gouge. The results showed a strong difference in the frictional weakening behaviour, with a lower slip velocity (around 5 mm/s) and lower frictional strength where there was no fault gouge between the sliding rock surfaces. The existence of the fault gouge layer delayed the onset of fault weakening. It is thought that flash heating may be the main active weakening mechanism. It is concluded that the use of low, intermediate and high slip velocity friction experiments with and without an intervening fault gouge layer is suitable for modelling rupture propagation in underground shear zones to forecast the severity of possible rockbursts, and improve safety.