Impact of intensified control on visceral leishmaniasis in a highly-endemic district of Bihar, India: an interrupted time series analysis.

Visceral leishmaniasis (VL) is declining in India and the World Health Organization's (WHO) 2020 'elimination as a public health problem' target has nearly been achieved. Intensified combined interventions might help reach elimination, but their impact has not been assessed. WHO's Neglected Tropical Diseases 2021-2030 roadmap provides an opportunity to revisit VL control strategies. We estimated the combined effect of a district-wide pilot of intensified interventions in the highly-endemic Vaishali district, where cases fell from 3,598 in 2012-2014 to 762 in 2015-2017. The intensified control approach comprised indoor residual spraying with improved supervision; VL-specific training for accredited social health activists to reduce onset-to-diagnosis time; and increased Information Education & Communication activities in the community. We compared the rate of incidence decrease in Vaishali to other districts in Bihar state via an interrupted time series analysis with a spatiotemporal model informed by previous VL epidemiological estimates. Changes in Vaishali's rank among Bihar's endemic districts in terms of monthly incidence showed a change pre-pilot (3rd highest out of 33 reporting districts) vs. during the pilot (9th) (p<1e-10). The rate of decline in Vaishali's incidence saw no change in rank at 11th highest, both pre-pilot & during the pilot. Counterfactual model simulations suggest an estimated median of 352 cases (IQR 234-477) were averted by the Vaishali pilot between January 2015 and December 2017, which was robust to modest changes in the onset-to-diagnosis distribution. Strengthening control strategies may have precipitated a substantial change in VL incidence in Vaishali and suggests this approach should be piloted in other highly-endemic districts.

The usefulness of trained field workers in diagnosis of post-kala-azar dermal leishmaniasis (PKDL) and clinico-epidemiological profile in highly endemic areas of Bihar.

BACKGROUND: Surveillance of post-kala-azar dermal leishmaniasis (PKDL) is critical to the elimination of visceral leishmaniasis (VL). In this study we assessed the feasibility of using trained field workers for detecting suspected PKDL cases. METHODS: A cross-sectional study using a multistage sampling technique was conducted in the Araria district of Bihar. Trained field workers were utilized for identification of suspected PKDL case. RESULTS: We investigated 57 099 individuals from 11 300 households. The trained field workers were useful in identifying 107 (18%) probable PKDL cases. The calculated PKDL prevalences were 18.7/10 000 and 9.7/10 000 for probable and confirmed PKDL cases, respectively. The median duration of onset of PKDL was 23 months (interquartile range 16.5-56.5). The younger age group developed PKDL significantly more often compared with the older age group (p=0.007). Of the 107 patients, 25 (55.5%) were positive by microscopy of slit skin smear and 42 (93.3%) by polymerase chain reaction. Of 45 patients, 33 (73%) PKDL cases were cured after full treatment. The risk of not being cured with incomplete treatment was three times higher than with complete treatment (relative risk 3.12 [95% confidence interval 1.23 to 8.67], p=0.004). CONCLUSIONS: We conclude that the prevalence of PKDL is high and the use of trained field workers may be feasible to actively detect PKDL cases in VL-endemic areas of Bihar, India.

Snowball Vs. House-to-House Technique for Measuring Annual Incidence of Kala-azar in the Higher Endemic Blocks of Bihar, India: A Comparison.

BACKGROUND: Visceral Leishmaniasis, commonly known as kala-azar, is widely prevalent in Bihar. The National Kala-azar Control Program has applied house-to-house survey approach several times for estimating Kala-azar incidence in the past. However, this approach includes huge logistics and operational cost, as occurrence of kala-azar is clustered in nature. The present study aims to compare efficiency, cost and feasibility of snowball sampling approach to house-to-house survey approach in capturing kala-azar cases in two endemic districts of Bihar, India. METHODOLOGY/PRINCIPAL FINDINGS: A community based cross-sectional study was conducted in two highly endemic Primary Health Centre (PHC) areas, each from two endemic districts of Bihar, India. Snowball technique (used to locate potential subjects with help of key informants where subjects are hard to locate) and house-to-house survey technique were applied to detect all the new cases of Kala-azar during a defined reference period of one year i.e. June, 2010 to May, 2011. The study covered a total of 105,035 households with 537,153 populations. Out of total 561 cases and 17 deaths probably due to kala-azar, identified by the study, snowball sampling approach captured only 221 cases and 13 deaths, whereas 489 cases and 17 deaths were detected by house-to-house survey approach. Higher value of McNemar's χ² statistics (64; p<0.0001) for house-to-house survey approach than snowball sampling and relative difference (>1) indicates that most of the kala-azar cases missed by snowball sampling were captured by house-to-house approach with 13% of omission. CONCLUSION/SIGNIFICANCE: Snowball sampling was not found sensitive enough as it captured only about 50% of VL cases. However, it captured about 77% of the deaths probably due to kala-azar and was found more cost-effective than house-to-house approach. Standardization of snowball approach with improved procedure, training and logistics may enhance the sensitivity of snowball sampling and its application in national Kala-azar elimination programme as cost-effective approach for estimation of kala-azar burden.

Pharmacovigilance of Miltefosine in Treatment of Visceral Leishmaniasis in Endemic Areas of Bihar, India.

Miltefosine, the only oral drug for visceral leishmaniasis (VL), is being used as the first-line drug under the VL elimination program in the Indian subcontinent. Miltefosine is an oral drug which was used as a topical application for skin metastasis of breast cancer. It was found to be effective against Leishmania donovani The main adverse events (AE) reported previously with miltefosine use includes diarrhea, vomiting, and dehydration. Other AEs include, raised serum alanine transaminase/aspartate aminotransferase and renal parameters such as creatinine. In this study, we report AEs in a large patient cohort of VL treated with miltefosine. The purpose of this pharmacovigilance study was to assess adverse drug reactions (ADRs)/AE of miltefosine treatment under unrestricted condition in the field setup. Patients were followed up to 6 months for therapeutic effectiveness. Outcomes of a larger data set of patients treated with this regimen from April 2012 to March 2015 were recorded. In the present study, 646 patients of VL were given miltefosine. Majority of the study subjects (58%) were male. Relapse occurred in 7% during follow-up period. Main causes of death were VL-pulmonary tuberculosis coinfection, extreme diarrhea, and acute pancreatitis which were reported in 1.7% subjects. Of 553 (85.6%) patients completing full course of treatment, 463 (83.7%) showed ADR with miltefosine during the study period. About 2.3% were suffering severe ADR, 51% from moderate, and the rest had mild ADR. The initial and final cure rate was 97.4% and 85.6%, respectively.

Visceral leishmaniasis diagnosis and reporting delays as an obstacle to timely response actions in Nepal and India.

BACKGROUND: To eliminate visceral leishmaniasis (VL) in India and Nepal, challenges of VL diagnosis, treatment and reporting need to be identified. Recent data indicate that VL is underreported and patients face delays when seeking treatment. Moreover, VL surveillance data might not reach health authorities on time. This study quantifies delays for VL diagnosis and treatment, and analyses the duration of VL reporting from district to central health authorities in India and Nepal. METHODS: A cross-sectional study conducted in 12 districts of Terai region, Nepal, and 9 districts of Bihar State, India, in 2012. Patients were interviewed in hospitals or at home using a structured questionnaire, health managers were interviewed at their work place using a semi-structured questionnaire and in-depth interviews were conducted with central level health managers. Reporting formats were evaluated. Data was analyzed using two-tailed Mann-Whitney U or Fisher's exact test. RESULTS: 92 VL patients having experienced 103 VL episodes and 49 district health managers were interviewed. Patients waited in Nepal 30 days (CI 18-42) before seeking health care, 3.75 times longer than in Bihar (8d; CI 4-12). Conversely, the lag time from seeking health care to receiving a VL diagnosis was 3.6x longer in Bihar (90d; CI 68-113) compared to Nepal (25d; CI 13-38). The time span between diagnosis and treatment was short in both countries. VL reporting time was in Nepal 19 days for sentinel sites and 76 days for "District Public Health Offices (DPHOs)". In Bihar it was 28 days for "District Malaria Offices". In Nepal, 73% of health managers entered data into computers compared to 16% in Bihar. In both countries reporting was mainly paper based and standardized formats were rarely used. CONCLUSIONS: To decrease the delay between onset of symptoms and getting a proper diagnosis and treatment the approaches in the two countries vary: In Nepal health education for seeking early treatment are needed while in Bihar the use of private and non-formal practitioners has to be discouraged. Reinforcement of VL sentinel reporting in Bihar, reorganization of DPHOs in Nepal, introduction of standardized reporting formats and electronic reporting should be conducted in both countries.

Clinical epidemiologic profile of a cohort of post-kala-azar dermal leishmaniasis patients in Bihar, India.

Post-kala-azar dermal leishmaniasis (PKDL) has important public health implications for transmission of visceral leishmaniasis (VL). Clinical and epidemiologic profiles of 102 PKDL patients showed that median age of males and females at the time of diagnosis was significantly different (P = 0.013). A significant association was observed between family history of VL and sex of PKDL patients (χ(2) = 5.72, P < 0.01). Nearly 33% of the patients showed development of PKDL within one year of VL treatment. The observed time (median = 12 months) between appearance of lesions and diagnosis is an important factor in VL transmission. A significant association was observed between type of lesions and duration of appearance after VL treatment (χ(2) = 6.59, P = 0.001). Because PKDL was observed during treatment with all currently used anti-leishmanial drugs, new drug regimens having high cure rates and potential to lower the PKDL incidence need to be investigated.

Asymptomatic infection with visceral leishmaniasis in a disease-endemic area in bihar, India.

A prospective study was carried out in a cohort of 355 persons in a leishmaniasis-endemic village of the Patna District in Bihar, India, to determine the prevalence of asymptomatic persons and rate of progression to symptomatic visceral leishmaniasis (VL) cases. At baseline screening, 50 persons were positive for leishmaniasis by any of the three tests (rK39 strip test, direct agglutination test, and polymerase chain reaction) used. Point prevalence of asymptomatic VL was 110 per 1,000 persons and the rate of progression to symptomatic cases was 17.85 per 1,000 person-months. The incidence rate ratio of progression to symptomatic case was 3.36 (95% confidence interval [CI] = 0.75-15.01, P = 0.09) among case-contacts of VL compared with neighbors. High prevalence of asymptomatic persons and clinical VL cases and high density of Phlebotomus argentipes sand flies can lead to transmission of VL in VL-endemic areas.