Design and methods for a quasi-experimental pilot study to evaluate the impact of dual active ingredient insecticide-treated nets on malaria burden in five regions in sub-Saharan Africa

Background:Vector control tools have contributed significantly to a reduction in malaria burden since 2000, primar‑ily through insecticidal‑treated bed nets (ITNs) and indoor residual spraying. In the face of increasing insecticide resist‑ance in key malaria vector species, global progress in malaria control has stalled. Innovative tools, such as dual active ingredient (dual‑AI) ITNs that are effective at killing insecticide‑resistant mosquitoes have recently been introduced. However, large‑scale uptake has been slow for several reasons, including higher costs and limited evidence on their incremental effectiveness and cost‑effectiveness. The present report describes the design of several observational studies aimed to determine the effectiveness and cost‑effectiveness of dual‑AI ITNs, compared to standard pyre‑throid‑only ITNs, at reducing malaria transmission across a variety of transmission settings.Methods:Observational pilot studies are ongoing in Burkina Faso, Mozambique, Nigeria, and Rwanda, leveraging dual‑AI ITN rollouts nested within the 2019 and 2020 mass distribution campaigns in each country. Enhanced surveil‑lance occurring in select study districts include annual cross‑sectional surveys during peak transmission seasons, monthly entomological surveillance, passive case detection using routine health facility surveillance systems, and studies on human behaviour and ITN use patterns. Data will compare changes in malaria transmission and disease burden in districts receiving dual‑AI ITNs to similar districts receiving standard pyrethroid‑only ITNs over three years. The costs of net distribution will be calculated using the provider perspective including financial and economic costs, and a cost‑effectiveness analysis will assess incremental cost‑effectiveness ratios for Interceptor® G2, Royal Guard®, and piperonyl butoxide ITNs in comparison to standard pyrethroid‑only ITNs, based on incidence rate ratios calcu‑lated from routine data.Conclusions:Evidence of the effectiveness and cost‑effectiveness of the dual‑AI ITNs from these pilot studies will complement evidence from two contemporary cluster randomized control trials, one in Benin and one in Tanzania, to provide key information to malaria control programmes, policymakers, and donors to help guide decision‑making and planning for local malaria control and elimination strategies. Understanding the breadth of contexts where these dual‑AI ITNs are most effective and collecting robust information on factors influencing comparative effectiveness could improve uptake and availability and help maximize their impact

Automated Cell Detection and Morphometry on Growth Plate Images of Mouse Bone

Microscopy imaging of mouse growth plates is extensively used in biology to understand the effect of specific molecules on various stages of normal bone development and on bone disease. Until now, such image analysis has been conducted by manual detection. In fact, when existing automated detection techniques were applied, morphological variations across the growth plate and heterogeneity of image background color, including the faint presence of cells (chondrocytes) located deeper in tissue away from the image’s plane of focus, and lack of cell-specific features, interfered with identification of cell. We propose the first method of automated detection and morphometry applicable to images of cells in the growth plate of long bone. Through ad hoc sequential application of the Retinex method, anisotropic diffusion and thresholding, our new cell detection algorithm (CDA) addresses these challenges on bright-field microscopy images of mouse growth plates. Five parameters, chosen by the user in respect of image characteristics, regulate our CDA. Our results demonstrate effectiveness of the proposed numerical method relative to manual methods. Our CDA confirms previously established results regarding chondrocytes’ number, area, orientation, height and shape of normal growth plates. Our CDA also confirms differences previously found between the genetic mutated mouse Smad1/5(CKO) and its control mouse on fluorescence images. The CDA aims to aid biomedical research by increasing efficiency and consistency of data collection regarding arrangement and characteristics of chondrocytes. Our results suggest that automated extraction of data from microscopy imaging of growth plates can assist in unlocking information on normal and pathological development, key to the underlying biological mechanisms of bone growth

Automated Cell Detection and Morphometry on Growth Plate Images of Mouse Bone.

Microscopy imaging of mouse growth plates is extensively used in biology to understand the effect of specific molecules on various stages of normal bone development and on bone disease. Until now, such image analysis has been conducted by manual detection. In fact, when existing automated detection techniques were applied, morphological variations across the growth plate and heterogeneity of image background color, including the faint presence of cells (chondrocytes) located deeper in tissue away from the image's plane of focus, and lack of cell-specific features, interfered with identification of cell. We propose the first method of automated detection and morphometry applicable to images of cells in the growth plate of long bone. Through ad hoc sequential application of the Retinex method, anisotropic diffusion and thresholding, our new cell detection algorithm (CDA) addresses these challenges on bright-field microscopy images of mouse growth plates. Five parameters, chosen by the user in respect of image characteristics, regulate our CDA. Our results demonstrate effectiveness of the proposed numerical method relative to manual methods. Our CDA confirms previously established results regarding chondrocytes' number, area, orientation, height and shape of normal growth plates. Our CDA also confirms differences previously found between the genetic mutated mouse Smad1/5CKO and its control mouse on fluorescence images. The CDA aims to aid biomedical research by increasing efficiency and consistency of data collection regarding arrangement and characteristics of chondrocytes. Our results suggest that automated extraction of data from microscopy imaging of growth plates can assist in unlocking information on normal and pathological development, key to the underlying biological mechanisms of bone growth

Additional file 1 of Changes in on-time vaccination following the introduction of an electronic immunization registry, Tanzania 2016-2018: interrupted time-series analysis

Additional file 1: Supplementary Table 1. Comparison of immunization coverage between data sources. Supplementary Table 2. Tanzania immunization schedule primary and adolescent infant vaccination schedule