SARS-CoV-2 seroprevalence and associated factors among outpatient attendees at health facilities in different provinces in Chad.

Background: Chad with 7,698 confirmed cases of infection and 194 deaths since the beginning of the COVID-19 pandemic, is one of the African countries with the lowest reported case numbers. However, this figure likely underestimates the true spread of the virus due to the low rate of diagnosis. The high rate of asymptomatic infections reflects the reality of SARS-CoV-2 transmission in Chad.

Evidence of Zika virus circulation in human and livestock in Chad.

Zika virus (ZIKV) is a major public health problem worldwide. After several reported outbreaks, the current extent of infections caused by this orthoflavivirus in the Sahel remains to be explored. We investigated the prevalence of neutralizing antibodies against ZIKV in the general population, in HIV-infected individuals and in livestock in Chad using a seroneutralization assay that ensures high specificity level.

Assessment of the knowledge, attitudes, and practices toward human tuberculosis amongst rural communities in Chad.

Introduction: Tuberculosis (TB) is an infectious zoonotic disease caused by bacteria belonging to the complex. In sub-Saharan African countries such as Chad, TB is endemic and causes a high burden on humans and animals through morbidity, mortality, and reduced productivity in livestock. To effectively prevent and control the disease, strong coordination between policymakers, health and veterinary services, civil society organizations, and communities is needed.

Comparative analysis of immunological biomarkers in COVID-19 and bacterial pneumonia.

Coronavirus disease 2019 (COVID-19) is a severe and infectious respiratory condition caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). This case-control study aimed to evaluate serum levels of various immunological markers in patients with COVID-19 compared to those with bacterial pneumonia and a healthy control group. Serum samples were collected from adult participants across various COVID-19 isolation centers, including Kassala State and Ahmed Gasim Hospital, between April and June 2021.

Community-based symptom reporting among agro-pastoralists and their livestock in Chad in a One Health approach.

One Health Syndromic Surveillance has a high potential for detecting early epidemiological events in remote and hard-to-reach populations. Chadian pastoralists living close to their animals and being socio-economically unprivileged have an increased risk for zoonosis exposure. Engaging communities in disease surveillance could also strengthen preparedness capacities for outbreaks in rural Chad.

Presence of neutralizing SARS-CoV-2 antibodies in asymptomatic population of N'Djamena, Chad.

Introduction: Neutralizing antibodies (NAbs) are an important specific defence against viral infections, as these antibodies bind to specific receptor(s) and block the viral entry. NAbs assessments are therefore useful in determining individual or herd immunity to SARS-CoV-2. This study aims to deepen the investigation by assessing the positivity rate of neutralizing anti-spike antibodies to understand the real protection of the studied population against SARS-CoV-2.

Investigation of optimized observation periods for estimating a representative home range of free-roaming domestic dogs.

Free-roaming domestic dogs (FRDD), as vectors of zoonotic diseases, are of high relevance for public health. Understanding roaming patterns of dogs can help to design disease control programs and disease transmission simulation models. Studies on GPS tracking of dogs report stark differences in recording periods.

Seroprevalence and associated risk factors of brucellosis, Rift Valley fever and Q fever among settled and mobile agro-pastoralist communities and their livestock in Chad.

Brucellosis, Rift Valley fever (RVF) and Q fever are zoonoses prevalent in many developing countries, causing a high burden on human and animal health. Only a few studies are available on these among agro-pastoralist communities and their livestock in Chad. The objective of our study was to estimate brucellosis, RVF and Q fever seroprevalence among Chadian agro-pastoralist communities and their livestock, and to investigate risk factors for seropositivity.

Global and regional governance of One Health and implications for global health security.

The apparent failure of global health security to prevent or prepare for the COVID-19 pandemic has highlighted the need for closer cooperation between human, animal (domestic and wildlife), and environmental health sectors. However, the many institutions, processes, regulatory frameworks, and legal instruments with direct and indirect roles in the global governance of One Health have led to a fragmented, global, multilateral health security architecture. We explore four challenges: first, the sectoral, professional, and institutional silos and tensions existing between human, animal, and environmental health; second, the challenge that the international legal system, state sovereignty, and existing legal instruments pose for the governance of One Health; third, the power dynamics and asymmetry in power between countries represented in multilateral institutions and their impact on priority setting; and finally, the current financing mechanisms that predominantly focus on response to crises, and the chronic underinvestment for epidemic and emergency prevention, mitigation, and preparedness activities.

Metabolic Pathways as a Novel Landscape in Pancreatic Ductal Adenocarcinoma.

Metabolism plays a fundamental role in both human physiology and pathology, including pancreatic ductal adenocarcinoma (PDAC) and other tumors. Anabolic and catabolic processes do not only have energetic implications but are tightly associated with other cellular activities, such as DNA duplication, redox reactions, and cell homeostasis. PDAC displays a marked metabolic phenotype and the observed reduction in tumor growth induced by calorie restriction with in vivo models supports the crucial role of metabolism in this cancer type.

[Epidemiology of leprosy in Chad from 2015 to 2019].

Introduction: leprosy is a disease found and unevenly distributed in Chad. Since 1997, the annual national prevalence has been less than 1/10000 inhabitants, the elimination threshold set by the World Health Organization (WHO). The purpose of this study is to describe epidemiological trends of leprosy in Chad between 2015 and 2019, in order to provide the necessary data for the development of more effective strategies for leprosy control.

Influence of COVID-19 on lymphocyte and platelet parameters among patients admitted to intensive care unit and emergency.

Objective: The aim of the study was to detect the effect of COVID-19 on lymphocyte and platelet parameters among Sudanese patients admitted to Intensive Care unit (ICU) and emergency (ER).

Patients And Methods: This cross-sectional study was carried out on a total of 787 Sudanese individuals (487 confirmed COVID-19 cases and 300 apparently healthy individuals as controls, in duration between April 2020 to December 2020). Platelets (PLTs) and platelet indices, mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT) and platelet larger cell ratio (PLCR) were investigated as part of the complete blood count (CBC) for the case and control group.

Evaluation of the feasibility and sustainability of the joint human and animal vaccination and its integration to the public health system in the Danamadji health district, Chad.

Background: One Health approaches such as the Joint human and animal vaccination programmes (JHAVP) are shown to be feasible and to increase health care access to hard-to-reach communities such as mobile pastoralists. However, the financial sustainability and the integration into the public health systems at the district level of such programmes are still challenging. The main objective of the present study was to give insight to the feasibility and financial sustainability of JHAVP integrated as part of the public health system in Chad.

Predictors of free-roaming domestic dogs' contact network centrality and their relevance for rabies control.

Free roaming domestic dogs (FRDD) are the main vectors for rabies transmission to humans worldwide. To eradicate rabies from a dog population, current recommendations focus on random vaccination with at least 70% coverage. Studies suggest that targeting high-risk subpopulations could reduce the required vaccination coverage, and increase the likelihood of success of elimination campaigns.

Comparative Study of Free-Roaming Domestic Dog Management and Roaming Behavior Across Four Countries: Chad, Guatemala, Indonesia, and Uganda.

Dogs play a major role in public health because of potential transmission of zoonotic diseases, such as rabies. Dog roaming behavior has been studied worldwide, including countries in Asia, Latin America, and Oceania, while studies on dog roaming behavior are lacking in Africa. Many of those studies investigated potential drivers for roaming, which could be used to refine disease control measures.

Evaluation of the sentinel surveillance system for influenza-like illnesses in the Greater Accra region, Ghana, 2018.

Background: Influenza-like Illness (ILI) is a medical diagnosis of possible influenza or another respiratory illness with a common set of symptoms. The deaths of four schoolchildren, during a pandemic influenza outbreak in December 2017 in Ghana, raised doubts about the ILI surveillance system's performance. We evaluated the ILI surveillance system in the Greater Accra region, Ghana, to assess the system's attributes and its performance on set objectives.

Vaccine hesitancy among mobile pastoralists in Chad: a qualitative study.

Background: Demand side barriers to vaccination among rural and hard-to-reach populations in Chad are not yet well understood. Although innovative approaches such as linking human and animal vaccination increase vaccination uptake among mobile pastoralist communities, vaccination coverage in these communities is still lower than for rural settled populations. We hypothesize that mobile pastoralists' communities in Chad face specific demand side barriers to access vaccination services.

Bottlenecks in the provision of antenatal care: rural settled and mobile pastoralist communities in Chad.

Objective: To assess antenatal care (ANC) coverage and analyse constraining factors for service delivery to rural settled and mobile populations in two districts in Chad.

Method: Data from cross-sectional household and health facility surveys in the two Chadian rural health districts were analysed. First, contact coverage of ANC services in the study area was estimated from household data as the proportion of women who visited health facilities to obtain ANC during their last pregnancy.

Transmission dynamics and elimination potential of zoonotic tuberculosis in morocco.

Bovine tuberculosis (BTB) is an endemic zoonosis in Morocco caused by Mycobacterium bovis, which infects many domestic animals and is transmitted to humans through consumption of raw milk or from contact with infected animals. The prevalence of BTB in Moroccan cattle is estimated at 18%, and 33% at the individual and the herd level respectively, but the human M. bovis burden needs further clarification.

Cost-effective control strategies for animal and zoonotic diseases in pastoralist populations.

Animal diseases and zoonoses abound among pastoralist livestock, which is composed of cattle, sheep, goats, yak, camels, llamas, reindeer, horses and donkeys. There is endemic and, periodically, epidemic transmission of highly contagious viral and bacterial diseases in Africa, Asia and Latin America. Pastoralist livestock is often multiparasitised with endo- and ectoparasites, as well as being affected by vectorborne viral and protozoal diseases.

Human and animal health surveys among pastoralists.

Valid human and livestock health surveys, including longitudinal follow-up, are feasible among mobile pastoralists and provide fundamental information to agencies for interventions that are responsive to realities and effective in addressing the needs of pastoralists. However, pastoralists are often excluded from studies, surveillance systems and health programmes. The occurrence of preventable and treatable diseases such as perinatal tetanus, measles and tuberculosis are indicative of limited access to health providers and information.

Trends in health surveillance and joint service delivery for pastoralists in West and Central Africa.

In most sub-Saharan African countries, pastoralism represents an important economic resource and contributes significantly to national growth; however, challenges remain, particularly in providing social services to pastoralists (especially health and education) and in avoiding conflict with local sedentary communities and local authorities. All of this takes place while pastoralists try to maintain their mobile lifestyle within a rapidly changing ecosystem. Transdisciplinary approaches, such as 'One Health', which covers both human and animal health, have proven effective in delivering services and reaching mobile pastoralists in remote areas.

A vision for the future of pastoralism.

Pastoral regions are challenged by social and ecological changes. Yet, there is increasingly robust evidence that pastoralism is a viable and sustainable livelihood and that pastoralists play a role in attaining the United Nations Sustainable Development Goals (SDGs). In this issue of the Scientific and Technical Review of the World Organisation for Animal Health (OIE), the authors take a broad view of pastoralism and pastoral livestock production from a number of different perspectives, taking into account societal and ecological viewpoints as well as issues of animal and human health.