A case for ongoing structural support to maximise infectious disease modelling efficiency for future public health emergencies: A modelling perspective.

This short communication reflects upon the challenges and recommendations of multiple COVID-19 modelling and data analytic groups that provided quantitative evidence to support health policy discussions in Switzerland and Germany during the SARS-CoV-2 pandemic. Capacity strengthening outside infectious disease emergencies will be required to enable an environment for a timely, efficient, and data-driven response to support decisions during any future infectious disease emergency. This will require 1) a critical mass of trained experts who continuously advance state-of-the-art methodological tools, 2) the establishment of structural liaisons amongst scientists and decision-makers, and 3) the foundation and management of data-sharing frameworks.

Mapping Global Bushmeat Activities to Improve Zoonotic Spillover Surveillance by Using Geospatial Modeling.

Human populations that hunt, butcher, and sell bushmeat (bushmeat activities) are at increased risk for zoonotic pathogen spillover. Despite associations with global epidemics of severe illnesses, such as Ebola and mpox, quantitative assessments of bushmeat activities are lacking. However, such assessments could help prioritize pandemic prevention and preparedness efforts. We used geospatial models that combined published data on bushmeat activities and ecologic and demographic drivers to map the distribution of bushmeat activities in rural regions globally. The resulting map had high predictive capacity for bushmeat activities (true skill statistic = 0.94). The model showed that mammal species richness and deforestation were principal drivers of the geographic distribution of bushmeat activities and that countries in West and Central Africa had the highest proportion of land area associated with bushmeat activities. These findings could help prioritize future surveillance of bushmeat activities and forecast emerging zoonoses at a global scale.

Human-Altered Landscapes and Climate to Predict Human Infectious Disease Hotspots.

BACKGROUND: Zoonotic diseases account for more than 70% of emerging infectious diseases (EIDs). Due to their increasing incidence and impact on global health and the economy, the emergence of zoonoses is a major public health challenge. Here, we use a biogeographic approach to predict future hotspots and determine the factors influencing disease emergence. We have focused on the following three viral disease groups of concern: Filoviridae, Coronaviridae, and Henipaviruses. METHODS: We modelled presence-absence data in spatially explicit binomial and zero-inflation binomial logistic regressions with and without autoregression. Presence data were extracted from published studies for the three EID groups. Various environmental and demographical rasters were used to explain the distribution of the EIDs. True Skill Statistic and deviance parameters were used to compare the accuracy of the different models. RESULTS: For each group of viruses, we were able to identify and map areas at high risk of disease emergence based on the spatial distribution of the disease reservoirs and hosts of the three viral groups. Common influencing factors of disease emergence were climatic covariates (minimum temperature and rainfall) and human-induced land modifications. CONCLUSIONS: Using topographical, climatic, and previous disease outbreak reports, we can identify and predict future high-risk areas for disease emergence and their specific underlying human and environmental drivers. We suggest that such a predictive approach to EIDs should be carefully considered in the development of active surveillance systems for pathogen emergence and epidemics at local and global scales.

Spatial variations in Leishmaniasis: A biogeographic approach to mapping the distribution of Leishmania species.

Cutaneous Leishmaniasis (CL) is the most prevalent form of Leishmaniasis and is widely endemic in the Americas. Several species of Leishmania are responsible for CL, a severely neglected tropical disease and the treatment of CL vary according to the different species of Leishmania. We proposed to map the distribution of the Leishmania species reported in French Guiana (FG) using a biogeographic approach based on environmental predictors. We also measured species endemism i.e., the uniqueness of species to a defined geographic location. Our results show that the distribution patterns varied between Leishmania spp. and were spatially dependent on climatic covariates. The species distribution modelling of the eco-epidemiological spatial patterns of Leishmania spp. is the first to measure endemism based on bioclimatic factors in FG. The study also emphasizes the impact of tree cover loss and climate on the increasing distribution of L. (Viannia) braziliensis in the most anthropized regions. Detection of high-risk regions for the different between Leishmania spp. is essential for monitoring and active surveillance of the vector. As climate plays a major role in the spatial distribution of the vector and reservoir and the survival of the pathogen, climatic covariates should be included in the analysis and mapping of vector-borne diseases. This study underscores the significance of local land management and the urgency of considering the impact of climate change in the development of vector-borne disease management strategies at the global scale.

Emerging human infectious diseases of aquatic origin: a comparative biogeographic approach using Bayesian spatial modelling.

BACKGROUND: With the increase in unprecedented and unpredictable disease outbreaks due to human-driven environmental changes in recent years, we need new analytical tools to map and predict the spatial distribution of emerging infectious diseases and identify the biogeographic drivers underpinning their emergence. The aim of the study was to identify and compare the local and global biogeographic predictors such as landscape and climate that determine the spatial structure of leptospirosis and Buruli Ulcer (BU). METHODS: We obtained 232 hospital-confirmed leptospirosis (2007-2017) cases and 236 BU cases (1969-2017) in French Guiana. We performed non-spatial and spatial Bayesian regression modeling with landscape and climate predictor variables to characterize the spatial structure and the environmental drivers influencing the distribution of the two diseases. RESULTS: Our results show that the distribution of both diseases is spatially dependent on environmental predictors such as elevation, topological wetness index, proximity to cropland and increasing minimum temperature at the month of potential infection. However, the spatial structure of the two diseases caused by bacterial pathogens occupying similar aquatic niche was different. Leptospirosis was widely distributed across the territory while BU was restricted to the coastal riverbeds. CONCLUSIONS: Our study shows that a biogeographic approach is an effective tool to identify, compare and predict the geographic distribution of emerging diseases at an ecological scale which are spatially dependent to environmental factors such as topography, land cover and climate.

Comparison of Mycobacterium ulcerans (Buruli ulcer) and Leptospira sp. (Leptospirosis) dynamics in urban and rural settings.

BACKGROUND: Zoonotic pathogens respond to changes in host range and/or pathogen, vector and host ecology. Environmental changes (biodiversity, habitat changes, variability in climate), even at a local level, lead to variability in environmental pathogen dynamics and can facilitate their transmission from natural reservoirs to new susceptible hosts. Whilst the environmental dynamics of aquatic bacteria are directly linked to seasonal changes of their habitat they also rely on the ecological processes underpining their transmission. However data allowing the comparison of these ecological processes are lacking. Here we compared the environmental dynamics of generalist and vector-borne aquatic bacterial pathogens in the same unit of time and space, and across rural and urban habitats in French Guiana (South America). PRINCIPAL FINDINGS: Using Leptospira sp. and Mycobacterium ulcerans we performed an environmental survey that allowed the detection of both pathogens in urban vs. rural areas, and during rainy vs. dry weather conditions. All samples were subjected to qPCR amplifications of LipL32 (Leptospira sp.) and IS2404 and KR (M. ulcerans) genetic markers. We found (i) a greater presence of M. ulcerans in rural areas compared with Leptospira sp., (ii) that modified urban environments were more favourable to the establishment of both pathogens, (iii) that Leptospira sp. presence was enhanced during the rainy season and M. ulcerans during the dry period, and (iv) differences in the spatial distribution of both bacteria across urban sites, probably due to the mode of dissemination of each pathogen in the environment. CONCLUSIONS: We propose that in French Guiana simplified and modified urban ecosystems might favour leptospirosis and Buruli ulcer emergence and transmission. Moreover, disease risk was also constrained by seasonality. We suggest that the prevention of aquatic bacterial disease emergence in impoverished urban areas of developing countries would benefit from seasonal diseases targeted surveys, which would maximise limited budgets from cash-strapped health agencies.

Packed red cells versus whole blood transfusion for severe paediatric anaemia, pregnancy-related anaemia and obstetric bleeding: an analysis of clinical practice guidelines from sub-Saharan Africa and evidence underpinning recommendations.

OBJECTIVE: Blood component transfusion is increasingly promoted in sub-Saharan Africa (SSA), but is resource-intensive so whole blood is often used. We examined SSA recommendations about whole blood and packed red cell transfusions for pregnancy-related bleeding or anaemia, and paediatric anaemia, and evaluated the evidence underpinning these recommendations. METHOD: Relevant SSA guidelines were identified using five electronic databases, websites for SSA Ministries of Health, blood transfusion services and WHO. To facilitate comparisons, indications for transfusing packed red cells or whole blood within these guidelines and reasons given for these recommendations were recorded on a pre-designed matrix. The AGREE II tool was used to appraise guidelines that gave a reason for recommending either packed red cells or whole blood. We systematically searched MEDLINE, CINAHL, Global Health, Cochrane library and NHSBT Transfusion Evidence Library, using PRISMA guidelines, for clinical studies comparing whole blood with packed red cells or combined blood components in obstetric bleeding or anaemia, or paediatric anaemia. Characteristics and findings of included studies were extracted in a standardised format and narratively summarised. RESULTS: 32 English language guidelines from 15 SSA countries mentioned packed red cell or whole blood use for our conditions of interest. Only seven guidelines justified their recommendation for using packed red cells or whole blood. No recommendations or justifications had supporting citations to research evidence. 33 full-text papers, from 11 234 citations, were reviewed but only one study met our inclusion criteria. This was a single-centre study in post-partum haemorrhage. CONCLUSION: Evidence comparing whole blood and packed red cell transfusion for common paediatric and maternal indications is virtually absent in SSA. Therefore, it is unclear whether policies promoting red cells over whole blood transfusion are clinically appropriate. Building a relevant evidence base will help develop effective policies promoting the most appropriate use of blood in African settings.

Clinical practice guidelines in India: Quality appraisal and the use of evidence in their development.

BACKGROUND: Guideline development in India has come under increased scrutiny with a growing interest in the use of evidence for guideline development. METHODS: Guidelines on the four leading causes of disability adjusted life years in India (ischemic heart disease, lower respiratory infections, chronic obstructive pulmonary diseases, tuberculosis), published on or after 2010 was searched in electronic databases and by other methods and their quality appraised by using the AGREE-II appraisal tool. In-depth, semistructured interviews were conducted with 15 individuals involved with the development of the included guidelines and the transcripts were analyzed using the framework approach. RESULTS: We included eleven guidelines. The median AGREE II domain scores was highest for "scope and purpose" (81%) and "clarity of presentation" (76%), and lowest for "rigor of development" (31%) and "editorial independence" (33%). Four main themes emerged from the interviews: (1) Guideline development in India was undergoing transition toward adoption of systematic, transparent and evidence-based approaches but several barriers in the form of attitudes toward use of evidence, lack of methodological capacity, inadequate governance structure and funding exist; (2) guideline development was an academic activity restricted to elite institutions and this affects panel composition, the consultative process and implementation of guidelines; (3) mixed views on patient involvement in guideline development; and (4) Taboo & Poor understanding of issues surrounding conflict of interests. CONCLUSION: A multitude of efforts is needed by issuing agencies and the government to ensure development of guidelines in transparent, evidence-based and a systematic manner with high quality in India.

Disability Among Ebola Survivors and Their Close Contacts in Sierra Leone: A Retrospective Case-Controlled Cohort Study.

Ebola survivors (21/27 [77.8%]) suffered more disability than their close contacts (6/54 [11.1%]) (adjusted odds ratio, 23.5 [95% confidence interval, 6.5-85.7]; P < .001) when measured by the Washington Group Disability Extended Questionnaire. Major limitations in vision, mobility, cognition, and affect were observed in survivors 1 year following the 2014-2016 Ebola outbreak, highlighting the need for long-term rehabilitation.