A Multi-Country, Single-Blinded, Phase 2 Study to Evaluate a Point-of-Need System for Rapid Detection of Leishmaniasis and Its Implementation in Endemic Settings

With the advancement of isothermal nucleic acid amplification techniques, detection of the pathogenic DNA in clinical samples at point-of-need is no longer a dream. The newly developed recombinase polymerase amplification (RPA) assay incorporated in a suitcase laboratory has shown promising diagnostic efficacy over real-time PCR in detection of leishmania DNA from clinical samples. For broader application of this point-of-need system, we undertook a current multi-country diagnostic evaluation study towards establishing this technique in different endemic settings which would be beneficial for the ongoing elimination programs for leishmaniasis. For this study purpose, clinical samples from confirmed visceral leishmaniasis (VL) and post-kala-azar dermal leishmaniasis (PKDL) patients were subjected to both real-time PCR and RPA assay in Bangladesh, India, and Nepal. Further skin samples from confirmed cutaneous leishmaniasis (CL) patients were also included from Sri Lanka. A total of 450 clinical samples from VL patients, 429 from PKDL patients, 47 from CL patients, and 322 from endemic healthy/healthy controls were under investigation to determine the diagnostic efficacy of RPA assay in comparison to real-time PCR. A comparative sensitivity of both methods was found where real-time PCR and RPA assay showed 96.86% (95% CI: 94.45–98.42) and 88.85% (95% CI: 85.08–91.96) sensitivity respectively in the diagnosis of VL cases. This new isothermal method also exhibited promising diagnostic sensitivity (93.50%) for PKDL cases, when a skin sample was used. Due to variation in the sequence of target amplicons, RPA assay showed comparatively lower sensitivity (55.32%) than that of real-time PCR in Sri Lanka for the diagnosis of CL cases. Except for India, the assay presented absolute specificity in the rest of the sites. Excellent concordance between the two molecular methods towards detection of leishmania DNA in clinical samples substantiates the application of RPA assay incorporated in a suitcase laboratory for point-of-need diagnosis of VL and PKDL in low resource endemic settings. However, further improvisation of the method is necessary for diagnosis of CL

Cluster survey evaluation of a measles vaccination campaign in Jharkhand, India, 2012.

India was the last country in the world to implement a two-dose strategy for measles-containing vaccine (MCV) in 2010. As part of measles second-dose introduction, phased measles vaccination campaigns were conducted during 2010-2013, targeting 131 million children 9 months to <10 years of age. We performed a post-campaign coverage survey to estimate measles vaccination coverage in Jharkhand state.A multi-stage cluster survey was conducted 2 months after the phase 2 measles campaign occurred in 19 of 24 districts of Jharkhand during November 2011-March 2012. Vaccination status of children 9 months to <10 years of age was documented based on vaccination card or mother's recall. Coverage estimates and 95% confidence intervals (95% CI) for 1,018 children were calculated using survey methods.In the Jharkhand phase 2 campaign, MCV coverage among children aged 9 months to <10 years was 61.0% (95% CI: 54.4-67.7%). Significant differences in coverage were observed between rural (65.0%; 95% CI: 56.8-73.2%) and urban areas (45.6%; 95% CI: 37.3-53.9%). Campaign awareness among mothers was low (51.5%), and the most commonly reported reason for non-vaccination was being unaware of the campaign (69.4%). At the end of the campaign, 53.7% (95% CI: 46.5-60.9%) of children 12 months to <10 years of age received ≥ 2 MCV doses, while a large proportion of children remained under-vaccinated (34.0%, 95% CI: 28.0-40.0%) or unvaccinated (12.3%, 95% CI: 9.3-16.2%).Implementation of the national measles campaign was a significant achievement towards measles elimination in India. In Jharkhand, campaign performance was below the target coverage of ≥ 90% set by the Government of India, and challenges in disseminating campaign messages were identified. Efforts towards increasing two-dose MCV coverage are needed to achieve the recently adopted measles elimination goal in India and the South-East Asia region

Cluster-level measles campaign vaccination coverage in the urban and rural surveys, Jharkhand, 2012.

<p>Organ-pipe plots of unweighted coverage by cluster were constructed for urban and rural surveys (Dale Rhoda, personal communication). Design effect (DE) and intraclass correlation coefficients (ICCs) were calculated for the respective surveys.</p

Socio-demographic characteristics of children in the urban and rural surveys, Jharkhand, 2012.

<p>Abbreviations: y = years, m = months</p><p>Socio-demographic characteristics of children in the urban and rural surveys, Jharkhand, 2012.</p

Phase 2 measles vaccination campaign coverage estimates by socio-demographic characteristic for urban and rural areas, Jharkhand, 2012.

<p>Abbreviations: LCL = lower confidence limit, UCL = upper confidence limit, y = years, m = months</p><p>^a Variations in denominator due to missing data</p><p>^b Rao-Scott chi-square test; p-values denoted with * are statistically significant</p><p>^c P-value is for comparison between urban and rural surveys</p><p>Phase 2 measles vaccination campaign coverage estimates by socio-demographic characteristic for urban and rural areas, Jharkhand, 2012.</p

Reasons for non-vaccination and awareness of the phase 2 measles vaccination campaign by urban and rural areas, Jharkhand, 2012.

<p>Abbreviations: ASHA = accredited social health activist, AWW = anganwadi workers, ANM = auxiliary nurse midwife</p><p>Reasons for non-vaccination and awareness of the phase 2 measles vaccination campaign by urban and rural areas, Jharkhand, 2012.</p

Measles Case Fatality Rate in Bihar, India, 2011–12

<div><p>Background</p><p>Updated estimates of measles case fatality rates (CFR) are critical for monitoring progress towards measles elimination goals. India accounted for 36% of total measles deaths occurred globally in 2011. We conducted a retrospective cohort study to estimate measles CFR and identify the risk factors for measles death in Bihar–one of the north Indian states historically known for its low vaccination coverage.</p><p>Methods</p><p>We systematically selected 16 of the 31 laboratory-confirmed measles outbreaks occurring in Bihar during 1 October 2011 to 30 April 2012. All households of the villages/urban localities affected by these outbreaks were visited to identify measles cases and deaths. We calculated CFR and used multivariate analysis to identify risk factors for measles death.</p><p>Results</p><p>The survey found 3670 measles cases and 28 deaths (CFR: 0.78, 95% confidence interval: 0.47–1.30). CFR was higher among under-five children (1.22%) and children belonging to scheduled castes/tribes (SC/ST, 1.72%). On multivariate analysis, independent risk factors associated with measles death were age <5 years, SC/ST status and non-administration of vitamin A during illness. Outbreaks with longer interval between the occurrence of first case and notification of the outbreak also had a higher rate of deaths.</p><p>Conclusions</p><p>Measles CFR in Bihar was low. To further reduce case fatality, health authorities need to ensure that SC/ST are targeted by the immunization programme and that outbreak investigations target for vitamin A treatment of cases in high risk groups such as SC/ST and young children and ensure regular visits by health-workers in affected villages to administer vitamin A to new cases.</p></div

Measles case fatality rate among SC/ST and G/OBC cases stratified by age group and vitamin A administration, Bihar, India.

<p>Measles case fatality rate among SC/ST and G/OBC cases stratified by age group and vitamin A administration, Bihar, India.</p

Flowchart showing measles case ascertainment, Bihar, India, 2011–12.

<p>Flowchart showing measles case ascertainment, Bihar, India, 2011–12.</p

Measles case fatality rate by selected variables, in 16 outbreaks, Bihar, India, October 2011 to April 2012.

<p>*MCV1 status of 455 (12.4%) of children was unknown, **Vitamin A administration status of 179 (4.9%) children was unknown.</p