Intensely clustered outbreak of visceral leishmaniasis (kala-azar) in a setting of seasonal migration in a village of Bihar, India.

BACKGROUND: A visceral leishmaniasis outbreak was reported from a village in a low-endemic district of Bihar, India. METHODS: Outbreak investigation with house-to-house search and rapid test of kala-azar suspects and contacts was carried out. Sandfly collection and cone bio-assay was done as part of entomological study. RESULTS: A spatially and temporally clustered kala-azar outbreak was found at Kosra village in Sheikhpura district with 70 cases reported till December 2018. Delay of more than a year was found between diagnosis and treatment of the index case. The southern hamlet with socio-economically disadvantaged migrant population was several times more affected than rest of the village (attack rate of 19.0% vs 0.5% respectively, ORMH = 39.2, 95% CI 18.2-84.4). The median durations between onset of fever to first contact with any health services, onset to kala-azar diagnosis, diagnosis to treatment were 10 days (IQR 4-18), 30 days (IQR 17-73) and 1 day (IQR 0.5 to 3), respectively, for 50 kala-azar cases assessed till June 2017. Three-fourths of these kala-azar cases had out-of-pocket medical expenditure for their condition. Known risk factors for kala-azar such as illiteracy, poverty, belonging to socially disadvantaged community, migration, residing in kutcha houses, sleeping in rooms with unplastered walls and non-use of mosquito nets were present in majority of these cases. Only half the dwellings of the kala-azar cases were fully sprayed. Fully gravid female P. argentipes collected post indoor residual spraying (IRS) and low sandfly mortality on cone-bioassay indicated poor effectiveness of vector control. CONCLUSIONS: There is need to focus on low-endemic areas of kala-azar. The elimination programme should implement a routine framework for kala-azar outbreak response. Complete case-finding, use of quality-compliant insecticide and coverage of all sprayable surfaces in IRS could help interrupt transmission during outbreaks.

Changing clinico-epidemiology of post-kala-azar dermal leishmaniasis (PKDL) in India: Results of a survey in four endemic states.

BACKGROUND & OBJECTIVES: Detection and treatment of post-kala-azar dermal leishmaniasis (PKDL) cases is considered important for kala-azar elimination. The objective of our study was to find out the proportion of different forms of lesions, interruption of treatment and rate of treatment completion, cure rates of PKDL, risk factors for developing severe forms of PKDL and utilization of services offered by the kala-azar elimination program. METHODS: A cross-sectional survey of PKDL patients registered for treatment at all levels of care during 2015 and 2016 was done. RESULTS: 576 PKDL patients who had started treatment in 2015 and 2016 were studied. Three-fourths of all patients were found to be clinically cured after a year of follow-up. Around 90% lesions were of macular type. Interruption of treatment was observed in one-fourth of PKDL patients. Median duration between kala-azar treatment and development of PKDL was 4.5 years. Around 79% patients had past history of kala-azar treatment. Discontinuation of treatment during earlier kala-azar episode was significantly associated with the development of papular and nodular forms of lesion. 43% of patients had received the incentive of INR 2000 after completion of treatment. Around three-fourths women in the reproductive age group were found not to use any contraceptive method during PKDL treatment. INTERPRETATION & CONCLUSION: PKDL treatment interruption should be reduced through ensuring drug supply and timely retrieval of patients. Directly observed treatment should be implemented and combination regimen should be explored to improve final cure rate. Delivery of financial incentive to PKDL patients and counselling and contraception to women of reproductive age group should be improved.