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Cutaneous myiasis caused by various Calliphoridae dipteran species is prevalent worldwide and is of particular veterinary and public health concern. Recently, in a scientific exploration of the Guinea Worm Eradication Program to Chad, Africa, we observed that dogs with mutilated ears, based on local awareness, were caused by cutaneous myiasis. In this study, we analyzed epidemiological, morphological, and molecular data on cutaneous myiasis in dogs from Chad. From September to October 2022, dogs (n = 1,562) from 56 villages situated along the Chari River were physically inspected for cutaneous myiasis. All larvae were collected and identified morphologically and by molecular analysis of the partial cytochrome oxidase c subunit I (COI) mitochondrial gene. The prevalence of myiasis infestation along with 95 % confidence intervals (95 % CI) was determined using the modified Wilson method. Myiasis was detected in dogs from 21 villages (37.5 %; 95 % CI 26 - 50 %), predominating in the southernmost region. Of 1,562 dogs, 66 (4.22 %; 95 % CI 3.34 - 5.34 %) were infested by calliphorid larvae, with a mean infestation of 2.28 larvae per animal (range = 1 to 24). Specimens were morphologically identified as Cordylobia anthropophaga (n = 94), Chrysomya bezziana (n = 54), and Chrysomya sp. (n = 3), which were detected in 57, eight and one dog, respectively. No co-infestations were observed. The molecular analyses confirmed the morphological identification and revealed the presence of 17 haplotypes for C. anthropophaga, 2 for C. bezziana, and one for Chrysomya sp. Our study emphasizes the veterinary importance of myiasis in dogs in Africa and proposes measures to assure their health and well-being., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Epilepsy is a significant public health problem. More than 50 million people worldwide live with epilepsy, and over three-quarters of them are in low- and middle-income countries. The situation in Chad regarding people with epilepsy is challenging to assess, starting from the shortage of scientific data, the inadequacy of technical facilities, the lack of human resources, and the inadequacy of government action. The Ministry of Health and Chadian Society of Neurology are looking forward to prioritizing epilepsy as well as improving the living conditions of persons with this disease. The epilepsy treatment issue is also problematic. Most of the patients are either off treatment or under-medicated. Few antiseizure medications (ASMs) are available, notably carbamazepine, phenobarbital, and valproic acid. Epilepsy remains little-known and does not seem to be a priority for decision-makers. We describe the current situation in Chad, to improve the conditions under which epilepsy is treated. PLAIN LANGUAGE SUMMARY: Epilepsies is a chronic brain problem that is common in poorer settings. The daily lives of people with epilepsy are chaotic in Chad. The challenges are numerous, particularly those related to health infrastructures, due to the lack of adequate diagnostic means and the lack of neurologists. The cultural and language challenges, especially since epilepsy is still considered the devil's disease and the name differs according to the dialects. Stigmatization is also frequent and is often responsible for school dropout, refusal, or dismissal from work. Care and prevention are daily challenges that require government action. Social coverage is insufficient and almost absent in rural areas. It is urgent to prioritize epilepsy in future action plans and also to increase awareness of the conditions to overcome these challenges., (© 2024 The Author(s). Epilepsia Open published by Wiley Periodicals LLC on behalf of International League Against Epilepsy.)

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. In this study, we estimated the seroprevalence and identified factors associated with SARS-CoV-2 infection., Methods: A cross-sectional study was conducted between September 2022 and February 2023. A total of 1,290 plasma samples were collected from outpatient attendees at Health Facilities located in 11 provinces of Chad and tested by ELISA method, for the presence of IgG antibodies to SARS-CoV2 nucleocapsid (N) protein. KoboToolbox was used to gather data from the participants and data were analyzed using STATA 16., Results: The overall seroprevalence was 83.0% [95% CI = 81.6%-85.5%], with variations between provinces, ranging from 99.2% [95% CI = 94.0%-100%] in Moundou (Southern Chad) to 46.8% [95% CI = 36.0% -57.1%] in Biltine (Eastern Chad). Factors associated with the seroprevalence included military occupation (OR = 0.37 CI [0.80-1.77] p = 0.025) and age group between 55-64 years (OR = 0.33 CI [0.15-0.72] p = 0.005). While, other factors, such as gender and age were not significantly associated with seroprevalence., Conclusion: Our results indicated that, the seroprevalence of COVID-19 in Chad is among the highest in Sub-Saharan Africa. These estimates could guide the response and public health policy decisions, enhancing the management of future outbreaks involving respiratory pathogens., Competing Interests: Declarations Ethics approval and consent to participate The study protocol was approved by the Chad National Bioethics Committee (CNBT) on 08 April 2022 under number: 011CMT/PC/PMT/MESRI/SG/CNBT/2022 and authorized by the Chad Ministry of Public Health under number: N°2326/CMT/PC/PMT/MSPSN/SE/SG/DGPC/DPERO/SRO/2022. The protocol was presented to 11 focal points including 10 provinces and N’Djamena selected for the study. Training sessions on the data collection tool were organized before the start of data and sample collection. An information sheet was given to each voluntary participant as well as the signature of informed consent and assent for minors. The informed consent was obtained from all participants involved. For adult participants (aged ≥ 16 years), informed consent was obtained directly from each individual. For minor participants (aged < 16 years), informed consent was obtained from parents or the legally authorized representative (LAR). In both cases, consent was obtained in accordance with the ethical guidelines established by the approving ethics committee. Each participant was assigned a unique code, and the data was handled confidentially. Consent for publication Not applicable. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Tick-borne pathogens in the genus Rickettsia are the causative agents of severe and potentially fatal spotted fever group (SFG) and typhus group diseases in dogs and humans. Climate, habitat, and land-use changes are impacting vector ranges, with expansions potentially resulting in novel pathogens being introduced into naïve locations. Despite the public health importance of SFG Rickettsia, there are relatively few data on the prevalence and diversity of rickettsial pathogens in sub-Saharan Africa. The aim of this study was to characterize the SFG Rickettsia prevalence and diversity in ixodid ticks (104 Amblyomma spp., 160 Rhipicephalus spp., and one Hyalomma truncatum) collected from domestic dogs in Chad, Africa. Ticks were screened for Rickettsia spp. using a nested PCR targeting the 17-kDa gene. Species identification was through bidirectional Sanger sequencing of the 17-kDa, ompA, ompB, and/or gltA gene targets. A total of 43.3 % (115/265) ticks were positive for Rickettsia spp. and six Rickettsia species were identified: R. africae, R. massiliae, R. conorii, R. felis, R. monacensis and Candidatus Rickettsia muridii. Seven additional samples were positive for Rickettsia of undetermined species. Rickettsia africae, an important zoonotic pathogen, was found in 81 % (79/97) of A. variegatum and 29 % (2/7) of an A. marmoreum complex species, a group that infests a wide range of birds and mammals, including humans. Finally, we detected a high diversity of Rickettsia spp., most of which were zoonotic, in Rh. muhsamae. Collectively these data indicate there is a risk of rickettsiosis in Chad and further studies on ticks and rickettsial pathogens in this region are warranted., (Copyright © 2024. Published by Elsevier GmbH.)

Q fever (QF) and Rift Valley fever (RVF) are endemic zoonotic diseases in African countries, causing significant health and economic burdens. Accurate prevalence estimates, crucial for disease control, rely on robust diagnostic tests. While enzyme-linked immunosorbent assays (ELISA) are not the gold standard, they offer rapid, cost-effective, and practical alternatives. However, varying results from different tests and laboratories can complicate comparing epidemiological studies. This study aimed to assess the agreement of test results for QF and RVF in humans and livestock across different laboratory conditions and, for humans, different types of diagnostic tests. We measured inter-laboratory agreement using concordance, Cohen's kappa, and prevalence and bias-adjusted kappa (PABAK) on 91 human and 102 livestock samples collected from rural regions in Chad. The serum aliquots were tested using ELISA in Chad, and indirect immunofluorescence assay (IFA) (for human QF and RVF) and ELISA (for livestock QF and RVF) in Switzerland and Germany. Additionally, we examined demographic factors influencing test agreement, including district, setting (village vs. camp), sex, age, and livestock species of the sampled individuals. The inter-laboratory agreement ranged from fair to moderate. For humans, QF concordance was 62.5%, Cohen's kappa was 0.31, RVF concordance was 81.1%, and Cohen's kappa was 0.52. For livestock, QF concordance was 92.3%, Cohen's kappa was 0.59, RVF concordance was 94.0%, and Cohen's kappa was 0.59. Multivariable analysis revealed that QF test agreement is significantly higher in younger humans and people living in villages compared to camps and tends to be higher in livestock from Danamadji compared to Yao, and in small ruminants compared to cattle. Additionally, RVF agreement was found to be higher in younger humans. Our findings emphasize the need to consider sample conditions, test performance, and influencing factors when conducting and interpreting epidemiological seroprevalence studies., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Hungerbühler et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Visceral leishmaniasis (VL), caused by the protozoan Leishmania donovani complex, is endemic in many parts of the world. Little known in Chad, VL has been recently documented from previously nonendemic areas. We report an epidemiological investigation of VL in the Léré district hospital in southwestern Chad. After informed consent, 40 VL patients were enrolled in the study. Diagnosis made using the formalin serological test was confirmed by polymerase chain reaction on blood samples. Clinical parameters were obtained from the physician or nurse caregiver, and from patients. Of a total of 40 serology positive patients, L. donovani DNA was found in 33 (82.5%), with 55% being male patients. The most affected age groups were 15-29 (47.5%) and 0-14 (32.5%) years. Fever, weight loss, and pallor were frequent symptoms. Notably, splenomegaly and hepatomegaly were uncommon clinical signs. Common comorbidities included malaria (25%) and hepatitis B (15%), followed by gastric ulcer (10%) and tuberculosis (7.5%). These comorbidities were concurrent with VL and were diagnosed microscopically in blood and serum for malaria and tuberculosis, respectively, and by the rapid diagnostic test using serum for hepatitis B and gastric ulcer. Thirty-five percent of cases were treated with meglumine antimoniate, and three patients (7.5%), all with comorbidities, died. Sixty percent of patients lived close to the main town. Our data demonstrate that VL is endemic in the health district of Léré. Improving health education regarding L. donovani infection in endemic areas of Chad and providing training of health workers on early detection and management of VL are needed to help save lives.

Women of reproductive age are particularly vulnerable to low-quality diets due to their higher micronutrients needs. The minimum dietary diversity for women (MDDW) is a proxy for micronutrient adequacy in this group of women. Its relationship with other aspects that lead to malnutrition is not fully elucidated and depends on the context. In this study, we assessed the prevalence of MDDW among women of a rural area in Chad and its association with socioeconomical, agricultural, dietary and food security data. A cross-sectional study was conducted. Following a multistage cluster sampling, 984 women of reproductive age were randomly selected and interviewed in March 2019. We obtained food consumption data through unquantified 24 h recalls and computed MDDW as consuming at least five out of 10 predefined food groups. We constructed a Food Production Diversity Score (FPDS) with crop and livestock information. We obtained multivariable logistic regression models including different covariates. MDDW was achieved by only 33% of women in the sample. In our final model, we identified a significant association of MDDW with the FPDS and gathering of wild plants. Women in households with the highest FPDS had 70% more chances of achieving MDDW than those with the lowest FPDS. Gathering wild plants doubled these chances. Areas of cultivated land, Water, Sanitation and Hygiene resources, and a high level of food security, measured with the Household Food Insecurity Access Scale, were also significantly related to the achievement of MDDW. This illustrates the importance of nutrition-sensitive policies, also considering biodiversity and food production diversification., (© 2024 European Commission. Maternal & Child Nutrition published by John Wiley & Sons Ltd.)

Background: Tick-borne pathogens are understudied among domestic animals in sub-Saharan Africa but represent significant threats to the health of domestic animals and humans. Specifically, additional data are needed on tick-borne pathogens in Chad, Africa. Surveillance was conducted among domestic dogs in Chad for selected tick-borne pathogens to measure (1) the prevalence of antibodies against Anaplasma spp., Borrelia burgdorferi, and Ehrlichia spp.; (2) the prevalence of infections caused by Hepatozoon spp., Ehrlichia canis, Anaplasma platys, and Babesia spp.; and (3) associations of pathogens with demographic, spatial, and temporal factors. Blood samples were collected from domestic dogs at three time points (May 2019, November 2019, June 2020) across 23 villages in southern Chad., Results: Of the 428 dogs tested with the IDEXX SNAP 4Dx test in May 2019, 86% (n = 370, 95% CI = 83-90%) were positive for antibodies to Ehrlichia spp., 21% (n = 88, 95% CI = 17-25%) were positive for antibodies to Anaplasma spp., and 0.7% (n = 3, 95% CI = 0.1-2%) were positive for antibodies to Borrelia burgdorferi. Four different pathogens were detected via PCR. Hepatozoon spp. were most commonly detected (67.2-93.4%, depending on the time point of sampling), followed by E. canis (7.0-27.8%), A. platys (10.1-22.0%), and Babesia vogeli (0.4-1.9%). Dogs were coinfected with up to three pathogens at a single time point, and coinfections were most common in May 2019 compared to November 2019 and May 2020., Conclusions: Overall, this study provides new data about the epidemiology of tick-borne pathogens in domestic dogs in Chad, with potential implications for dog and human health., (© 2024. The Author(s).)

Introduction: Pneumococcal meningitis outbreaks occur sporadically in the African meningitis belt. Outbreak control guidelines and interventions are well established for meningococcal but not pneumococcal meningitis. Mathematical modelling is a useful tool for assessing the potential impact of different pneumococcal control strategies. This work aimed to estimate the impact of reactive vaccination with pneumococcal conjugate vaccine (PCV) had it been implemented in past African meningitis belt outbreaks and assess their efficiency relative to existing routine infant immunisation with PCV., Methods & Results: Using recent pneumococcal meningitis outbreaks in Burkina Faso, Chad, and Ghana as case studies, we investigated the potential impact of reactive vaccination. We calculated the number needed to vaccinate to avert one case (NNV) in each outbreak setting and over all outbreaks and compared this to the NNV for existing routine infant vaccination. We extended previous analyses of reactive vaccination by considering longer-term protection in vaccinees over five years, incorporating a proxy for indirect effects. We found that implementing reactive vaccination in previous pneumococcal meningitis outbreaks could have averted up to 10-20 % of outbreak cases, with the biggest potential impact in Brong Ahafo, Ghana (2015-2016) and Goundi, Chad (2009). The NNV, and hence the value of reactive vaccination, varied greatly. 'Large' (80 + cumulative modelled cases per 100,000 population) and/or 'prolonged' (exceeding a response threshold of 10 suspected cases per 100,000 per week for four weeks or more) outbreaks had NNV estimates under 10,000. For routine infant vaccination with PCV, the estimated NNV ranged from 3,100-5,600 in Burkina Faso and 1,500-2,600 in Ghana., Implications: This analysis provides evidence to inform the design of pneumococcal meningitis outbreak response guidelines. Countries should consider reactive vaccination in each outbreak event, together with maintaining routine infant vaccination as the primary intervention to reduce pneumococcal disease burden and outbreak risk., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Community engagement is a strategy commonly used in health and development programming. Many disease eradication programs engage with communities through different structures and mechanisms to detect, report, contain, and respond to the diseases they target. Qualitative operational research was conducted in a district of Chad co-endemic for both dracunculiasis (i.e., Guinea worm disease) and circulating vaccine-derived poliovirus to reveal factors influencing community engagement behavior in the context of eradication-related programming. Women and men from six communities and stakeholders from the local, district, and central levels were recruited to participate in focus group discussions and semi-structured in-depth interviews. A thematic analysis was performed to identify barriers and facilitators of community engagement. Barriers to community engagement included mistrust in exogenously established health program initiatives (i.e., initiatives designed by partners external to targeted program communities) resulting from negative past experiences with external entities and community groups and the lure of profit-motivating community engagement. Subgroup and intersectionality analyses revealed that gender and other identities influence whether and to what extent certain members of the community engage in a meaningful way. Facilitators of community engagement included leadership and the influence of authorities and leaders in community participation, perceived benefits of being engaged with community-based initiatives, and use of incentives to enhance community participation. Study findings may be used to inform the refinement of community engagement approaches in Chad and learning agendas for other "last mile" disease eradication programs.

A comprehensive understanding of the spatial distribution and correlates of infection are key for the planning of disease control programs and assessing the feasibility of elimination and/or eradication. In this work, we used species distribution modeling to predict the environmental suitability of the Guinea worm (Dracunculus medinensis) and identify important climatic and sociodemographic risk factors. Using Guinea worm surveillance data collected by the Chad Guinea Worm Eradication Program (CGWEP) from 2010 to 2022 in combination with remotely sensed climate and sociodemographic correlates of infection within an ensemble machine learning framework, we mapped the environmental suitability of Guinea worm infection in Chad. The same analytical framework was also used to ascertain the contribution and influence of the identified climatic risk factors. Spatial distribution maps showed predominant clustering around the southern regions and along the Chari River. We also identified areas predicted to be environmentally suitable for infection. Of note are districts near the western border with Cameroon and southeastern border with Central African Republic. Key environmental correlates of infection as identified by the model were proximity to permanent rivers and inland lakes, farmlands, land surface temperature, and precipitation. This work provides a comprehensive model of the spatial distribution of Guinea worm infections in Chad 2010-2022 and sheds light on potential environmental correlates of infection. As the CGWEP moves toward elimination, the methods and results in this study will inform surveillance activities and help optimize the allocation of intervention resources.

Age and sex influence the risk of childhood wasting. We aimed to determine if wasting treatment outcomes differ by age and sex in children under 5 years, enroled in therapeutic and supplementary feeding programmes. Utilising data from stage 1 of the ComPAS trial, we used logistic regression to assess the association between age, sex and wasting treatment outcomes (recovery, death, default, non-response, and transfer), modelling the likelihood of recovery versus all other outcomes. We used linear regression to calculate differences in mean length of stay (LOS) and mean daily weight gain by age and sex. Data from 6929 children from Kenya, Chad, Yemen and South Sudan was analysed. Girls in therapeutic feeding programmes were less likely to recover than boys (pooled odds ratio [OR]: 0.84, 95% confidence interval [CI]: 0.72-0.97, p = 0.018). This association was statistically significant in Chad (OR: 0.61, 95% CI: 0.39-0.95, p = 0.030) and Yemen (OR: 0.47, 95% CI: 0.27-0.81, p = 0.006), but not in Kenya and South Sudan. Multinomial analysis, however, showed no difference in recovery between sexes. There was no difference between sexes for LOS, but older children (24-59 months) had a shorter mean LOS than younger children (6-23 months). Mean daily weight gain was consistently lower in boys compared with girls. We found few differences in wasting treatment outcomes by sex and age. The results do not indicate a need to change current programme inclusion requirements or treatment protocols on the basis of sex or age, but future research in other settings should continue to investigate the aetiology of differences in recovery and implications for treatment protocols., (© 2023 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.)

Background: The main vectors of onchocerciasis in Africa are Simulium damnosum sensu lato, which transmit the causative agent Onchocerca volvulus. The force of transmission is driven by the vector density, hence influencing the disease prevalence and intensity. Onchocerciasis is currently targeted for elimination using mass drug administration (MDA) of ivermectin, a potent microfilaricide. MDA in Cameroon began in 1987 in the Vina Valley, an endemic cross-border area with Chad, known for high vector densities and precontrol endemicity. Evaluations in 2008-2010 in this area showed ongoing transmission, while border areas in Chad were close to interrupting transmission. This study aimed to evaluate transmission in this area after several rounds of MDA since the last evaluation surveys., Methods: Black flies were collected by human landing catches at seven border sites in Cameroon, twice a week, from August 2021 to March 2022. A fraction of the flies was dissected for parity assessment and identification of Onchocerca larval stages. The transmission indices were estimated. Black fly larvae were also collected from the breeding sites at the fly catching sites and identified to species level by cytotaxonomy., Results: A total of 14,303 female flies were collected, and 6918 were dissected. Of these, 4421 (64.0%) were parous. The total biting rates were high, reaching up to 16,407 bites/person/study period, and transmission potential (third-stage larvae (L3) from head/all L3) were 367/702, 146/506, 51/55, 20/32, 0/3, 0/0, and 0/0 infective larvae/person, respectively, for Mbere-Tchad, Babidan, Hajam/V5, Gor, Djeing, Touboro, and Koinderi. Infectivity rates (L3 from head) were 16.00, 12.75, 5.15, and 4.07 infective females (L3H)/1000 parous flies for Haijam, Mbere-Tchad, Babidan, and Gor, respectively. These values exceed the World Health Organization (WHO) thresholds of ≤ 20 annual transmission potential (ATP) or < 1 infective female/1000 parous females. The major vectors identified were Simulium damnosum sensu stricto, S. squamosum, and for the first time in the area, S. yahense., Conclusions: More than 20 years of MDA has not eliminated onchocerciasis in the study area; hence, this area is a potential source of reintroduction of onchocerciasis in Chad and would require alternative treatment strategies. Many factors such as MDA efficiency, effectiveness of ivermectin, and cytospecies composition may be contributing to transmission persistence., (© 2024. The Author(s).)

Background: Dental caries is a global disease that can have disabling effects. In Africa, its prevalence in schools is very variable, due to the great variability of food habits and oral hygiene. This study aimed to assess the prevalence of dental caries, associated factors, and to research oral pathologies associated with that dental decay in one circumscription of the city of N'Djamena., Material and Methods: This was a cross-sectional study conducted in 3 schools in the 7th borough of the city of N'Djamena. A total of 360 pupils aged between 6 and 12 years were recruited between October 2021 and September 2022. Each participant underwent to an oral examination which consisted in looking carefully at the pupil's face (cheeks, lips) to note any deformities or possible facial asymmetry, and to check for any sensation of pain in any part of the face. In another hand, the oral examination aimed to look for any decay on all the teeth and determine the category and class of it. Finally, the personal data (age, sex, class, parents' occupations) of each participant and the results of his oral examination were collected into a database and analyzed., Results: A total of 185 pupils had at least one decayed tooth, giving a prevalence rate of 51.4%. Among them, 45% had at least 2 decayed teeth. The school attended and snacking between meals were significantly associated with the presence of caries (p<0.05). Teeth 36 (lower left first molar) and 46 (lower right first molar) were the most often affected by caries (21% and 22% respectively). The mixt DMF index was 0.6 and the overall frequency of decayed teeth was 51.9%. According to Black's classification, class II caries was the most prevalent (48%), while according to Baume's classification, category II was the most prevalent (54%). The time of brushing, the material and the type of product used significantly influenced the appearance of caries (p<0.05). Participants with dental dyschromia had more tooth decay., Conclusion: Caries was prevalent in the targeted schools and represented a real problem for pupils. Implementing an oral health policy based on preventive dentistry by raising awareness among children and their parents would contribute to the proper education of pupils., (Copyright © 2024 SFMTSI.)

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. This study describes a retrospective cross-sectional survey that collected data on clinical symptoms reported in people and livestock in Chadian agro-pastoral communities. In January-February 2018, interviews were conducted in rural households living in nomadic camps or settled villages in the Yao and Danamadji health districts. The questionnaire covered demographic data and symptoms reported in humans and animals for the hot, wet, and cold seasons over the last 12 months. Incidence rates of human and animal symptoms were comparatively analyzed at the household level. Ninety-two households with a homogeneous socio-demographic distribution were included. We observed cough and diarrhea as the most frequent symptoms reported simultaneously in humans and animals. In all species, the incidence rate of cough was significantly higher during the cold season, and diarrhea tended to occur more frequently during the wet season. However, the incidence rate of cough and diarrhea in animals did not predict the incidence rate of these symptoms in humans. Overall, the variations in reported symptoms were consistent with known seasonal, regional, and sociological influences on endemic diseases. Our retrospective study demonstrated the feasibility of collecting relevant health data in humans and animals in remote regions with low access to health services by actively involving community members. This encourages establishing real-time community-based syndromic surveillance in areas such as rural Chad., Competing Interests: Declaration of competing interest None of the authors have competing interests., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Introduction: Infection by hepatitis B virus (HBV) is a major issue in public health. The prevalence of HBV in Chad is 12.4%, all age groups considered. Here, we aimed to determine the prevalence of HBV and its associated factors among university students in N'Djamena, the country's capital., Methods: A cross-sectional survey of students at either the University of N'djamena or Emi Koussi University was conducted from 3 to 23 July 2021. All participating students provided signed, informed consent and were included in the study consecutively. Blood samples were collected, and serum tested for hepatitis B surface antigen (HBsAg) using the Determine HBsAg rapid test kit, with confirmation of positive tests on an Abbott Architect i1000SR analyzer. Descriptive analysis and logistic regression were used to determine associations between the outcome variable and independent/covariate variables., Results: A total of 457 students with a median age of 24 years were included across different faculties. The prevalence of HBV infection was 14.87% (68/457). Most students (75%) were aged 25 years or less. Unprotected sex was reported by 64.9% of the students and multiple sexual partners by 53.6%. Furthermore, 45.7% of them reported having no knowledge of hepatitis B. Having an HBsAg-positive mother (AOR: 2.11), having a history of transcutaneous medical procedures (AOR: 2.97) and living with a family (AOR: 4.63) were significantly associated with HBV status. Age ≥26 years appeared as a protective factor (AOR = 0.41)., Conclusion: Our study detected a high, 14.87% prevalence of HBV infection among students in N'djamena, Chad, and shed light on its associated factors. HBV prevention strategies should include raising awareness among students, making full hepatitis vaccination mandatory before children begin school, promoting mass screening to identify and treat chronic HBV carriers and reduce transmission, and reducing the cost of vaccination., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Debsikréo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Chad has seen a considerable reduction in cases of Guinea worm disease (or dracunculiasis) in domestic dogs in recent years. Tethering of dogs and application of Abate® larvicide to water sources appear to have contributed to this progress, but with 767 reported dog cases in 2021, accelerating elimination of the disease in Chad may require additional tools. We investigate the potential benefits of a hypothetical diagnostic test that could be capable of detecting prepatent infections in dogs. We adapt an agent-based simulation model for forecasting the impact of interventions on guinea worm disease in dogs to examine the interaction of multiple test factors including test accuracy, when the test can detect infection, dog selection, and dog-owner compliance with tethering recommendations. We find that a diagnostic test could be successful if used in conjunction with existing interventions, and elimination can be achieved within 2 years with 80% or higher test sensitivity, 90% or higher specificity, systematic testing of each dog twice per year, and more than 90% long-term tethering compliance when a dog tests positive or a worm is emerging. Because of the long incubation period of Guinea worm disease (10-14 months) and the fact that no treatment exists, the benefits of the test rely on the testing rollout and response of dog owners. If the test could estimate the timing of worm emergence, long-term tethering could be eliminated and infected dogs could be tethered only when the worms are expected, minimizing the related resources (human and financial) to support the intervention.

Background - Rationale: Tsetse flies (Diptera: Glossinidae) are obligate bloodfeeders that occur exclusively in Sub-Saharan Africa, where they are the vectors of trypanosomes causing HAT (human African trypanosomiasis) and AAT (African animal trypanosomiasis). In Chad, tsetse flies occur only in the most southern part of the country because of its favorable bioclimatic conditions. However, despite the importance of HAT and AAT in this country, very little is known about the current tsetse distribution, in particular its northern limit, which is of key importance for the surveillance of these diseases., Material and Methods - Results: A total of 217 biconical traps were deployed in 2021 and 2022 from the West to the East around the formerly known northern limit, resulting in 1,024 tsetse caught belonging to three different taxa: Glossina morsitans submorsitans (57%), G. tachinoides (39%) and G. fuscipes fuscipes (4%). In addition to the information gathered on the presence/absence of each tsetse taxon, we show a strong North-South shift of the northen tsetse distribution limit as compared to the previous works from 1966 to 1996, and a growing spatial fragmentation in more and more discrete pockets of tsetse presence., Discussion - Conclusion: This North-South shift of the northern tsetse distribution limit in Chad is the likely consequence of the combined effect of severe draughts that affected the country, and increasing human pressure on land. This update of the tsetse northern limit will be of help to the national programmes in charge of HAT and AAT., (Copyright © 2024 SFMTSI.)

Background: Group A Rotaviruses (RVA) is one of the most common causes of severe diarrhoea in infants and children under 5 years of age. Unlike many countries in the world where RVA surveillance/control is active, in Chad , there is currently no applied RVA immunization program and surveillance strategy. The present study aims to determine the prevalence and associated risk factors of RVA gastroenteritis among children under five years of age in N'Djamena., Method: This study comprised two parts: (1) A cross-sectional study carried in four hospitals in N'Djamena between August and November 2019, to determine infection risk factors and evidence of RVA infection among children aged five and below, consulted or hospitalized for diarrhea. An ELISA based RVA VP6 protein detection was used to determine RVA infection prevalence. Infection results and sociodemographic data were statistically analysed to determine RVA infection risk factors. (2) A retrospective study that consisted of analysing the records of stool examinations of the period from January 2016 to December 2018, to determine the prevalence of infectious gastroenteritis among the target population., Results: For the cross-sectional study, RVA infection prevalence was 12.76% (18/141) with males (61.11%) being more affected (sex ratio: 1.57). Children below 12 months were the most affected age group (44.44%) and 44.4% were malnourished. The mean Vesikari score shows that 38.8% of children have a high severity level and 41.1% have a moderate level. For the retrospective study, 2,592 cases of gastroenteritis hospitalization were analysed; 980 out of 2,592 cases (37.81%) of hospitalization due to diarrhoea were due to diarrhoeagenic pathogens including Emtamoeba hystolitica, Gardia lamblia, Trichomonas hominis, Hymenolepis nana, Escherichia coli, Shigella spp, Proteus mirabilis, and Klebsiella oxytoca. Cases of diarrhoea with negative pathogen search were 1,612 cases (62.19%). The diarrhoea peak was observed during the dry seasons, and the age group under 11 months was the most affected was (57.3%)., Conclusion: This study describes the evidence of RVA infection among diarrhoeic children below five years of age in N'Djamena, thus indicates a serious health burden. Malnourishment younger age was the higher risk factor. Further studies are needed to determine the circulating strains prior to considering introduction of RVA vaccine and setup a routine rotavirus surveillance in Chad., (© 2024. The Author(s).)

Chad has one of the highest maternal and infant mortality rates in the world. Efforts to reduce these rates have led to the introduction of fee exemption and community involvement initiatives to further encourage the use of health services. Despite the introduction of these initiatives, inequalities in access to and use of health facilities persist. The aim of this study is to understand why and how the same action, implemented in a quasi-homogeneous way, produced contrasting results in different health centers. A multiple, contrasting case study was used to analyze the outcomes of pediatrics consultations and deliveries in four health centers in the Bénoye and Beinamar districts. Data were collected through individual interviews (n=26) and focus groups (n=22) with women beneficiaries, community health workers, and health care providers. The qualitative software QDA Miner was used to process the data. The study revealed that the organizational and managerial capacities of the providers and community actors would explain the heterogeneity of the results observed. Contextual factors such as the remoteness of services or the impassability and dangerousness of roads accentuated the disparities in the results observed. The results of this study show that human and contextual factors would explain the heterogeneity of the observed effects.

Tsetse flies (genus Glossina) transmit deadly trypanosomes to human populations and domestic animals in sub-Saharan Africa. Some foci of Human African Trypanosomiasis due to Trypanosoma brucei gambiense (g-HAT) persist in southern Chad, where a program of tsetse control was implemented against the local vector Glossina fuscipes fuscipes in 2018 in Maro. We analyzed the population genetics of G. f. fuscipes from the Maro focus before control (T0), one year (T1), and 18 months (T2) after the beginning of control efforts. Most flies captured displayed a local genetic profile (local survivors), but a few flies displayed outlier genotypes. Moreover, disturbance of isolation by distance signature (increase of genetic distance with geographic distance) and effective population size estimates, absence of any genetic signature of a bottleneck, and an increase of genetic diversity between T0 and T2 strongly suggest gene flows from various origins, and a limited impact of the vector control efforts on this tsetse population. Continuous control and surveillance of g-HAT transmission is thus recommended in Maro. Particular attention will need to be paid to the border with the Central African Republic, a country where the entomological and epidemiological status of g-HAT is unknown., (© S. Ravel et al., published by EDP Sciences, 2024.)

The impact of the coronavirus disease 2019 (COVID-19) pandemic on the clinical follow-up of people living with HIV (PLWH) remains poorly documented in Sahelian Africa. We conducted a monocentric retrospective investigation of the outcomes (loss to follow-up [LTFU], transferred, or dead) among a cohort of PLWH receiving antiretroviral treatment (ART) in N'djamena, Chad (December 2019-December 2022). The incidence of LTFU was found to be higher in 2020 than in 2022 (P > 10-4), with increases of incidence of LTFU in the first trimester of 2020 before identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection cases in Chad. The all-cause mortality was low and did not appear to be influenced by SARS-CoV-2 infection waves. Our data reveal a concerning trend of significantly increased LTFU among PLWH receiving ART during the COVID-19 pandemic. Our findings indicate that it is crucial to provide accurate information to ensure the continuity of care for PLWH during a sanitary crisis in Sahelian Africa.

Background: Understanding seasonal patterns in nutritional status is critical for achieving and tracking global nutrition goals. However, the majority of nutrition seasonality research design draws on 2 or 3 within-year time points based on existing assumptions of seasonality, missing a more nuanced pattern., Objective: We aimed to identify the intra-year variability of childhood wasting, severe wasting, and weight-for-height z-scores (WHZ) in a dryland single wet-season context and illustrate an analytical approach for improving analysis of the seasonality of nutritional status., Methods: To quantify the intra-year variability in nutritional status, we use data from a 23-month panel study (May 2018 to March 2020) following 231 children (6-59 months of age) in eastern Chad. We apply a mixed-effects harmonic regression with child- and village-level fixed effects on the odds of being wasted, severely wasted, and on WHZ, testing for multiple and nonsymmetrical seasonal peaks, adjusted for child sex and age. We triangulate our findings using climate data on temperature, vegetation, and precipitation., Results: We identify 2 annual peaks of wasting and severe wasting. Wasting peaks at 14.7% (confidence interval [CI], 11.8-18.2) at the end of the dry season, while the smaller peak corresponds to the start of the harvest period at 13.4% (CI, 10.7-16.6). The odds of being wasted decline during the rainy season to 11.8% (CI, 9.4-14.7), with the lowest prevalence of 8.8% (CI, 6.9-11.1) occurring during the start of the dry season. In addition, a 1°C monthly increase in temperature is significantly associated with a 5% (CI, 1.4-8.7) and 12% (CI, 3.0-20.3) increase in the odds that a child is wasted and severely wasted, respectively., Conclusions: Intra-year variability of child wasting is far more complex and nuanced than identified by the literature, with 2 peaks, as opposed to 1, likely corresponding to different seasonal drivers, such as food insecurity, disease, water contamination, and care practices at different times of year. Better seasonality analysis can go a long way in improving the timing and content of programming with the goal of reducing child wasting., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Chad suffers from protracted hunger, facing high food insecurity (Integrated Food Security Phase Classification 3 and above), and acute malnutrition levels that surpass the emergency threshold (15% global acute malnutrition) yearly. The Food Security Sector, with European Union support, leads an inclusive effort to increase synergy between humanitarian, development, and peace-building actors to understand and address drivers of hunger., Objective: To understand the spatial distribution of child wasting and household food insecurity and systemic drivers (conflict, livelihoods, vegetation, cultural norms) as well as better understand the relationship between child wasting and household food insecurity in Kanem and Bahr el Ghazal (BeG) region, Chad, with the goal of improving nexus programming and targeting., Methods: A cross-sectional randomized cluster survey was conducted in August 2021 in Kanem and BeG across 86 villages, reaching 7002 households and 6136 children. Data were collected on child anthropometry, household food security, and livelihoods. Using mixed methods, primary data were triangulated with secondary geospatial data on vegetation index and conflicts as well as qualitative interviews with local actors. Analysis was conducted using comparison tests, linear and logistic crude, and adjusted models, as well as looking at the design effect as a measure of clustering of outcomes at the community level., Results: The geospatial distribution of hunger indicators shows child wasting and food insecurity are highly clustered. However, communities with a high prevalence of child wasting were not those with the highest levels of food insecurity, indicating different pathways. Clustering of food insecurity and child wasting is due to basic drivers of conflict, health, and seasonal access to natural resources., Conclusions: The high levels of food insecurity and child wasting are each concentrated in specific survey clusters and are not necessarily connected. They result from different causal pathways at the community level linked to the systemic drivers of the rule of access to natural resources, environmental seasonality, and livelihoods. This suggests a greater need for an integrated humanitarian, development, and peace-building interventions to address the persistent high prevalence of food insecurity and child wasting. It also suggests that these community-level and systemic drivers require greater consideration from the start in research design and data collection., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Chad's total fertility rate (TFR) is 6.4 children per woman, compared with no more than 5.5 in neighbouring countries: Cameroon and the Central African Republic. Scientific research on the determinants of fertility in Chad should therefore be carried out in order to show decision-makers how they can strengthen their actions in this area. This is the aim of this study, which focuses on the influence of women's autonomy on fertility in Chad. Analyses of data from the Multiple Indicator and Demographic and Health Survey (DHS/MICS) conducted in Chad in 2014/2015 and a qualitative survey conducted in the same country in 2020 show, among other things, that 1) in socio-cultural groups characterised by strong gender inequalities, women's autonomy is positively associated with their desired fertility; 2) in these and other groups characterised by less gender inequality, women's autonomy is negatively associated with their actual fertility, all things being equal; 3) the hypotheses explaining this relationship differ across sociocultural groups: In highly gender- inegalitarian groups, the frequent death of children leads couples in which women have either little or no autonomy to compensate with high fertility, whereas in less gender- inegalitarian groups, the negative association between women's autonomy and fertility is due to late union formation, union dissolution, the fertility-reducing effects of breastfeeding and modern contraception, and other intermediate fertility variables not considered here. These findings highlight both the importance of designing development programmes in Chad that focus on women's empowerment and the need for such programmes to take sufficient account of the socio-cultural contexts in which the populations concerned live., Competing Interests: The Authors declared no conflict of interest, (African Journal of Reproductive Health © 2023.)

Despite considerable data generated on livestock trypanosomoses in tsetse-infested areas, little attention was paid for animal African trypanosomosis (AAT) in sleeping sickness foci. This study aimed to fill this gap by determining the diversity and prevalence of trypanosome species in animals from three Chadian human African trypanosomosis (HAT) foci. Blood samples were collected from 443 goats, 339 sheep, 228 dogs and 98 pigs of the Mandoul, Maro and Moissala HAT foci in the south of Chad. Capillary tube centrifugation (CTC) and specific primers were used to search trypanosomes. The prevalence of trypanosome infections was 6.3% for CTC and 22.7% for PCR. Trypanosomes of the sub-genus Trypanozoon had the highest prevalence (16.6%) while T. congolense savannah (1.9%) was least prevalent. Significant differences were recorded between the prevalence of trypanosome species (χ 2  = 8.34; p = 0.04) and HAT foci (χ 2  = 24.86; p ≤0.0001). Maro had the highest prevalence (32.7%) and Mandoul the lowest (17.4%). Significant differences were also recorded for T. congolense forest (χ 2  = 45.106; p < 0.0001) and all T. congolense (χ 2  = 34.992; p < 0.0001). Goats had the highest prevalence (26.9%) and sheep the lowest one (18.6%). Between animals, significant differences were recorded for trypanosomes of the sub-genus Trypanozoon (χ 2  = 9.443; p = 0.024), T. congolense forest (χ 2  = 10.476; p = 0.015) and all T. congolense (χ 2  = 12.152; p = 0.007). Of the 251 animals carrying trypanosome infections, 88.8% had single infections while 11.2% had more than one trypanosome species. The overall prevalence of single and mixed trypanosome infections were respectively 20.1% and 2.6% in animal taxa of all foci. This study highlighted a diversity of trypanosomes in animal taxa of all HAT foci. It showed that AAT constitutes a threat for animal health and animal breeding in Chadian HAT foci. In these tsetse infested areas, reaching the elimination of AAT requires the designing and the implementation of control measures against trypanosome infections., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Introduction: les dyslipidémies constituent un facteur de risque majeur dans la survenue des maladies cardio-vasculaires. La recherche de ce facteur et sa prise en charge adéquate contribuerait à prévenir ces maladies qui sont la plus grande cause de décès dans le monde. L'objectif de cette étude était d'évaluer la prévalence des dyslipidémies au laboratoire de biochimie du Centre Hospitalier Universitaire de Référence Nationale de N'Djamena. MATéRIEL ET MéTHODES: il s'agissait d'une étude transversale d'une durée de cinq ans (2015-2020) portant sur tous les patients ayant au moins un paramètre lipidique dans le registre du laboratoire. Les méthodes enzymatiques sur un automate de biochimie de type Cobas Integra 400 (Roche Diagnostics) ont été utilisées pour le dosage de cholestérol total, LDL-c, HDL-c et de triglycérides., Results: Au total 2038 patients avec une prédominance masculine (sex-ratio :1,33), ont été enregistrés, l'âge moyen de nos patients était de 56,45±8,8 ans. La prévalence des dyslipidémies était de 44,2%. Les différents types des dyslipidémies étaient repartis comme suit : l'hypercholestérolémie (40,52%) ; l'hyper LDLémie (33,02%) ; l'hypoHDLémie (14,72%) ; l%hypertriglyc%rid%mie (11,72%) et l'hyperlipidémie mixte (40,5%). On notait une évolution croissante de la prévalence de dyslipidemie au cours des cinq années de periode d'étude., Conclusions: la forte prévalence des dyslipidémies dans notre étude témoigne d'une situation préoccupante au Tchad, d'où l'intérêt d'étudier la prévalence des dyslipidémies et des autres facteurs de risque cardiovasculaire à l'échelle nationale et l'utilité d'organiser des campagnes d'éducations et d'informations sur les maladies cardiovasculaires et les facteurs de risque cardiovasculaire afin de r'duire cette pr'valence., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Guinea worm (GW) disease (or dracunculiasis) is currently transmitted among dogs in Chad, which presents risks for the human population. We studied how interventions implemented at different levels might reduce the spread of GW disease (geographically and over time) and what levels of interventions might accelerate elimination. We built a multiple-water-source agent-based simulation model to analyze the disease transmission among dogs in Chad, as well as in geographic district clusters, and validated it using local infection data. We considered two interventions: 1) tethering, where infected dogs are kept on a leash during periods of infectivity, and 2) Abate®, under which the water source is treated to reduce infectivity. Our results showed that elimination (0 dog infections) is most likely achieved within 5 years with extremely high levels of tethering (95%) and Abate (90%), when intervention levels are uniform across district clusters. We used an optimization model to determine an improved strategy, with intervention levels which minimize the number of dogs newly infected in the 6th year, under limitations on intervention levels across clusters; the number of dogs infected after 5 years of intervention could be reduced by approximately 220 dogs with an optimized strategy. Finally, we presented strategies that consider fairness based on intervention resource levels and outcomes. Increased tethering and Abate resources above historical levels are needed to achieve the target of GW disease elimination; optimization methods can inform how best to target limited resources and reach elimination faster.

Background: Cross-sectional surveys using the Standardized Monitoring and Assessment of Relief and Transitions methodology have been conducted annually in Chad since 2015 to evaluate population-level nutritional status., Objective: This analysis characterizes national and subnational trends in child wasting and women's thinness from 2015 to 2021 in Chad and identifies risk factors during the COVID-19 pandemic., Methods: Annual survey data with 12,000 to 15,000 households were included. Wasting was estimated for children 6 to 59 months using the WHO child growth standards, and among women 15 to 49 years, thinness was defined as mid-upper arm circumference <23 cm. Trends were stratified by agroecological zone, and chi-square tests used to assess statistical significance. Simple and multivariate logistic regression models were conducted for 2020 and 2021 to identify risk factors of wasting and thinness., Results: About 11,958 to 17,897 children and 9883 to 15,535 women contributed values each year. National wasting and thinness rates did not significantly decrease over the 7-year period (wasting: 14.1% to 12.1%, P = .43; thinness: 15.2% to 13.4%, P = .51) and wasting rose from 2020 to 2021. The Saharan and Sahelian zones had consistently higher rates compared to the Sudanian zone. Younger age, male sex, inadequate infant and young child feeding practices, and poorer household socio-economic factors were associated with greater odds of child wasting. For women, younger age, lack of nutrition knowledge, and poorer household socio-economic factors increased the odds of thinness., Conclusions: Undernutrition in Chad has not improved since 2015, and the COVID-19 pandemic likely exacerbated the crisis among children nationally and among women subnationally. Multisectoral approaches and regional targeting of interventions are recommended.

Human African trypanosomiasis, caused by the gambiense subspecies of Trypanosoma brucei (gHAT), is a deadly parasitic disease transmitted by tsetse. Partners worldwide have stepped up efforts to eliminate the disease, and the Chadian government has focused on the previously high-prevalence setting of Mandoul. In this study, we evaluate the economic efficiency of the intensified strategy that was put in place in 2014 aimed at interrupting the transmission of gHAT, and we make recommendations on the best way forward based on both epidemiological projections and cost-effectiveness. In our analysis, we use a dynamic transmission model fit to epidemiological data from Mandoul to evaluate the cost-effectiveness of combinations of active screening, improved passive screening (defined as an expansion of the number of health posts capable of screening for gHAT), and vector control activities (the deployment of Tiny Targets to control the tsetse vector). For cost-effectiveness analyses, our primary outcome is disease burden, denominated in disability-adjusted life-years (DALYs), and costs, denominated in 2020 US$. Although active and passive screening have enabled more rapid diagnosis and accessible treatment in Mandoul, the addition of vector control provided good value-for-money (at less than $750/DALY averted) which substantially increased the probability of reaching the 2030 elimination target for gHAT as set by the World Health Organization. Our transmission modelling and economic evaluation suggest that the gains that have been made could be maintained by passive screening. Our analysis speaks to comparative efficiency, and it does not take into account all possible considerations; for instance, any cessation of ongoing active screening should first consider that substantial surveillance activities will be critical to verify the elimination of transmission and to protect against the possible importation of infection from neighbouring endemic foci., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Antillon et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

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. We conducted a multi-stage cross-sectional serological survey in two rural health districts, Yao and Danamadji (966 human and 1041 livestock (cattle, sheep, goat and equine) samples)). The true seroprevalence were calculated applying a Bayesian framework to adjust for imperfect diagnostic test characteristics and accounting for clustering in the study design. Risk factors for each of the zoonotic diseases were estimated using mixed effects logistic regression models. The overall prevalence for brucellosis, Q fever and RVF combined for both regions was estimated at 0.2% [95% credibility Interval: 0-1.1], 49.1% [%CI: 38.9-58.8] and 28.1% [%CI: 23.4-33.3] in humans, and 0.3% [%CI: 0-1.5], 12.8% [%CI: 9.7-16.4] and 10.2% [%CI: 7.6-13.4] in animals. Risk factors correlating significantly with the respective disease seropositivity were sex for human brucellosis, sex and Q fever co-infection for animal brucellosis, age for human Q fever, species and brucellosis co-infection for animal Q fever, age and herd-level animal RVF seroprevalence within the same cluster for human RVF, and cluster-level human RVF seroprevalence within the same cluster for animal RVF. In Danamadji and Yao, Q fever and RVF are notably seroprevalent among agro-pastoralist human and animal communities, while brucellosis appears to have a low prevalence. Correlation between the seroprevalence between humans and animals living in the same communities was detected for RVF, highlighting the interlinkage of human and animal transmissible diseases and of their health, highlighting the importance of a One Health approach., Competing Interests: The authors declare that no competing interests exist for the present study., (Copyright: © 2023 Özcelik et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: This paper aims the decomposition of the multidimensional Gini coefficient by deprivation to investigate how aggregate multidimensional poverty inequality translates into inequality within each of its components. This approach provides a better understanding of the distribution of deprivations held, the standard of living of the population and makes recommendations on government policies., Method: We use the method of Lerman and Yitzhaki (1985), which allows us to identify the impact of marginal changes on multidimensional inequality (fuzzy poverty inequality)., Results: The data used come from the Household Budget and Consumption Surveys of 2003 of 6695 households, 2011 of 9259 households and 2018 of 7493 households. Empirical findings suggest that the Gini index in 2003 is 0.229, 0.215 in 2011 and 0.180 in 2018., Conclusions: The different social policies to reduce multi-inequalities must mainly be oriented towards health policies and access to drinking water, which are unequally distributed during the three periods. And social policies to reduce inequality in education, sanitation and housing are also to be taken into account., (Copyright © 2023 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.)

Introduction: The treatment of osteoarticular infections in Africa is a medical and surgical challenge due to the difficulties in managing antibiotic therapy after the surgical procedure. The objectives of this study were to identify the types of bacteria in osteoarticular lesions in patients treated in Chad and to determine the spectrum of resistance encountered and the efficacy of available antibiotics., Material and Methods: This is a retrospective study of all intraoperative osteoarticular and soft tissue samples taken in a French Role 2 Medical Treatment Facility of N'Djamena during surgery for chronic osteoarticular infections, in Chad, for 1 year., Results: A total of 160 bacterial strains were identified, with a predominance of Gram-negative bacillus (GNB) and staphylococcus infections. Among staphylococci, 80% were methicillin-sensitive streptococci which were generally multidrug-sensitive. Enterococci were resistant to third-generation cephalosporins, first-generation fluoroquinolones and gentamycin. Among GNB, there was a predominance of enterobacteria compared with non-fermenting GNB, of which 52% were multidrug-resistant and produced extended spectrum beta-lactamases (ESBL)., Conclusion: Staphylococcus aureus infections are most often sensitive to available antibiotics and therefore have better prognoses than infections caused by other bacteria. In contrast, in half of the cases of GNB, infections were caused by bacteria producing ESBL, thus posing the problem of multidrug-resistance, the risks of which are increased in precarious situations. Therefore, the type of bacteria appears to be a major prognostic factor in the treatment of osteoarticular infections in a Role 2 in Chad. This criterion will need to be considered before any treatment decisions are made., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Human African trypanosomiasis (HAT) is a neglected tropical disease caused by Trypanosoma brucei gambiense transmitted by tsetse flies in sub-Saharan West Africa. In southern Chad the most active and persistent focus is the Mandoul focus, with 98% of the reported human cases, and where African animal trypanosomosis (AAT) is also present. Recently, a control project to eliminate tsetse flies (Glossina fuscipes fuscipes) in this focus using the sterile insect technique (SIT) was initiated. However, the release of large numbers of sterile males of G. f. fuscipes might result in a potential temporary increase in transmission of trypanosomes since male tsetse flies are also able to transmit the parasite. The objective of this work was therefore to experimentally assess the vector competence of sterile males treated with isometamidium for Trypanosoma brucei brucei., Methods: An experimental infection was set up in the laboratory, mimicking field conditions: the same tsetse species that is present in Mandoul was used. A T. b. brucei strain close to T. b. gambiense was used, and the ability of the sterile male tsetse flies fed on blood with and without a trypanocide to acquire and transmit trypanosomes was measured., Results: Only 2% of the experimentally infected flies developed an immature infection (midgut) while none of the flies developed a metacyclic infection of T. b. brucei in the salivary glands. We did not observe any effect of the trypanocide used (isometamidium chloride at 100 mg/l) on the development of infection in the flies., Conclusions: Our results indicate that sterile males of the tested strain of G. f. fuscipes were unable to cyclically transmit T. b. brucei and might even be refractory to the infection. The data of the research indicate that the risk of cyclical transmission of T. brucei by sterile male G. f. fuscipes of the strain colonized at IAEA for almost 40 years appears to be small., (© 2023. The Author(s).)

Vaccination against the COVID-19 virus is currently the best option to combat the SARS-CoV-2 pandemic worldwide. However, in addition to logistical and economic barriers, hesitancy to be vaccinated threatens to jeopardize efforts to contain the disease. An increasing number of people in Africa are delaying or rejecting recommended vaccines. Since their launch, COVID-19 vaccines have frequently faced rejection worldwide. In this study, we interviewed 5,174 participants from Chad that were representative of the general population, on their perception of COVID-19 vaccines. The survey was conducted from April to May 2021, before the rollout of the COVID-19 vaccination. We found that 47.9% of respondents were willing to receive the COVID-19 vaccine, 29.8% were undecided and 22.3% would not accept the vaccine. We found that urban residents were much more likely to refuse the vaccine than rural residents. We also observed that distrust of COVID-19 vaccines and mistaken beliefs played a crucial role in the reluctance to be vaccinated. Hesitancy to vaccinate against COVID-19 was strongly associated with lack of knowledge, and acceptance of vaccination was primarily associated with fear of the disease. Finally, we identified population profiles among the undecided and the refractors, which will help in developing strategies to combat COVID-19 vaccine resistance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Takoudjou Dzomo, Mbario, Djarma, Soumbatingar, Madengar, Djimera, Djindimadje, Nguemadjita, Nassaringar, Bernales, Nangerngar, Naissem, Paningar, Gomez-Virseda, Lopez Barreda, Robbins, Cournil, Visier, Tuaillon and Mennechet.)

Although a diversity of trypanosome species have been detected in various animal taxa from human African trypanosomosis (HAT) foci, cattle trypanosomosis has not been addressed in HAT foci of west and central African countries including Chad. This study aimed to determine the prevalence of pathogenic trypanosome species in cattle from three HAT foci of the south of Chad. Blood samples were collected from 1466 randomly selected cattle from HAT foci of Mandoul, Maro, and Moïssala in the south of Chad. For each animal, the sex, age and body condition were recorded. Rapid diagnostic test (RDT) was used to search Trypanosoma brucei gambiense antibodies while the capillary tube centrifugation (CTC) test and PCR-based methods enabled to detect and identify trypanosome species. From the 1466 cattle, 45 (3.1%) were positive to RDT. The prevalence of trypanosome infections revealed by CTC and PCR-based method were respectively 2.7% and 11.1%. Trypanosomes of the subgenus Trypanozoon were dominant (6.5%) followed by T. congolense savannah (2.9%), T. congolense forest (2.5%) and T. vivax (0.8%). No animal was found with DNA of human infective trypanosome (T. b. gambiense). The overall prevalence of trypanosome infections was significantly higher in animal from the Maro HAT focus (13.8%) than those from Mandoul (11.1%) and Moïssala HAT foci (8.0%). This prevalence was also significantly higher in animal having poor body condition (77.5%) than those with medium (11.2%) and good (0.5%) body condition. The overall prevalence of single and mixed infections were respectively 9.4% and 1.6%. This study revealed natural infections of several pathogenic trypanosome species in cattle from different HAT foci of Chad. It showed similar transmission patterns of these trypanosome species and highlighted the need of developing control strategies for animal African trypanosomosis (AAT) with the overarching goal of improving animal health and the economy of smallholder farmers., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Vourchakbé et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Neglected tropical diseases pose a threat to domestic animal health, as domestic animals can serve as reservoirs for certain zoonotic parasitic infections, including Guinea worm (Dracunculus medinensis) and lymphatic filariasis. Surveillance for these parasites in domestic animals is needed to understand infection prevalence and transmission cycles, with the goal of instituting appropriate interventions. The goal of this research was to report our finding of Brugia sp. infection in dogs from Chad, Africa, and to characterize the genetics and epidemiology of the parasite. During a recent Chadian canine pathogen surveillance project, we identified Brugia sp. infections in a total of 46 out of 428 dogs (10.7%) sampled at three time points in 2019-2020. We found high levels of sequence similarity to B. malayi and B. pahangi based on amplification of 18S rRNA, 5.8S rRNA, and ITS-2 regions. Phylogenetic analysis of 18S rRNA gene sequences placed the Chadian Brugia sp. in a clade with other Brugia spp. but grouped it separately from both B. malayi and B. pahangi. Analysis of Hha I sequences showed the greatest similarity with B. patei, a parasite previously reported from dogs, cats, and wildlife hosts in Kenya. Epidemiologic analysis using generalized linear regression modeling found significantly higher odds of Brugia sp. detection among dogs in villages in southern Chad compared to those in the northern region. Further, within the northern region, there were higher odds of detection in the dry season, compared to the wet season, which is consistent with the ecology of a presumably mosquito-borne parasite. The same 428 dogs were tested for Dirofilaria immitis antigen using a commercial assay (IDEXX SNAP 4Dx) at the earliest time point of the study, with 119 dogs testing positive. However, no association was noted between Brugia infection and a dog being positive for Di. immitis antigen, with only seven of the 119 Di. immitis antigen-positive dogs being Brugia-positive. This is the first report of Brugia sp. in domestic dogs in Chad and additional research is needed to definitively identify the species present, elucidate transmission, and understand potential risks to canine and human health., Competing Interests: Declaration of Competing Interest None., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Early initiation of breastfeeding (EIB) is an inexpensive practice but has a substantial potential to reduce neonatal morbidity. Therefore, this study investigated the maternal and child-related factors associated with EIB and makes recommendations that could help improve the practice in Chad., Methods: We used data from the children's recode file of the 2014-2015 Chad Demographic and Health Survey. A total of 3991 women ages 15-49 y who had last-born children in the 2 y preceding the survey were included in our study. The outcome variable for the study was EIB. Both descriptive (frequencies and percentages) and inferential (binary logistic regression) analyses were carried out. All results of the binary logistic analyses are presented as adjusted odds ratios (aORs) with 95% confidence intervals (CIs)., Results: We found the prevalence of EIB in Chad to be 23.8%. In terms of maternal factors, the likelihood of EIB was high among non-working women (aOR 1.37 [95% CI 1.18 to 1.59]), the richest wealth quintile women (aOR 1.37 [95% CI 1.04 to 1.79]) and non-media-exposed women (aOR 1.58 [95% CI 1.24 to 2.02]) compared with working women, the poorest wealth quintile women and media-exposed women, respectively. EIB was lower among children whose mothers had one to three antenatal care visits (ANC; aOR 0.73 [95% CI 0.61 to 0.87]) and four or more ANC visits (aOR 0.80 [95% CI 0.66 to 0.97]) compared with those who had no ANC visits. With the child factors, EIB was higher among mothers of children who were smaller than average size at birth compared with those of larger than average birth size (aOR 1.47 [95% CI 1.24 to 1.74]). Mothers of children of fifth-order or more births compared with those of first-order births (aOR 1.51 [95% CI 1.07 to 2.12]) and those who were delivered through vaginal birth compared with those delivered through caesarean section (aOR 4.71 [95% CI 1.36 to 16.24]) were more likely to practice EIB., Conclusions: Maternal and child-related factors play roles in EIB in Chad. Hence, it is important to consider these factors in maternal and neonatal health interventions. Such initiatives, including training of outreach health workers, health education, counselling sessions and awareness-raising activities on breastfeeding geared towards EIB should be undertaken. These should take into consideration the employment status, wealth quintile, exposure to mass media, size of the baby at birth, ANC visits, parity and delivery method., (© The Author(s) 2021. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)

Background: Unskilled birth attendance is a major public health concern in Sub-Saharan Africa (SSA). Existing studies are hardly focused on the socio-demographic correlates and geospatial distribution of unskilled birth attendance in Chad (a country in SSA), although the country has consistently been identified as having one of the highest prevalence of maternal and neonatal deaths in the world. This study aimed to analyse the socio-demographic correlates and geospatial distribution of unskilled birth attendance in Chad., Methods: The study is based on the latest Demographic and Health Survey (DHS) data for Chad. A total of 10,745 women aged between 15 and 49 years were included in this study. A multilevel analysis based on logistic regression was conducted to estimate associations of respondents' socio-demographic characteristics with unskilled birth attendance. Geographic Information System (GIS) mapping tools, including Getis-Ord Gi hotspot analysis tool and geographically weighted regression (GWR) tool, were used to explore areas in Chad with a high prevalence of unskilled birth attendance., Results: The findings show that unskilled birth attendance was spatially clustered in four Chad departments: Mourtcha, Dar-Tama, Assoungha, and Kimiti, with educational level, occupation, birth desire, birth order, antenatal care, and community literacy identified as the spatial predictors of unskilled birth attendance. Higher educational attainment, higher wealth status, cohabitation, lowest birth order, access to media, not desiring more births, and higher antenatal care visits were associated with lower odds of unskilled birth attendance at the individual level. On the other hand, low community literacy level was associated with higher odds of unskilled birth attendance in Chad whereas the opposite was true for urban residency., Conclusions: Unskilled birth attendance is spatially clustered in some parts of Chad, and it is associated with various disadvantaged individual and community level factors. When developing interventions for unskilled birth attendance in Chad, concerned international bodies, the Chad government, maternal health advocates, and private stakeholders should consider targeting the high-risk local areas identified in this study., (© 2022. The Author(s).)

Objective: To analyze implementation of the maternal death surveillance and response (MDSR) strategy in Chad., Methods: Secondary data analysis of results from a cross-sectional study involving semistructured interviews with decision-makers at central, regional, and district levels, health providers, and technical and financial partners, and a document review. Data collection took place from June-July 2017., Results: Maternal death reporting was incorporated into the Integrated Disease Surveillance and Response system but did not include neonatal deaths nor maternal and neonatal deaths in communities. Underreporting of maternal deaths owing to fear of repercussions was evident, likely associated with maternal deaths reported at monthly meetings held by the country's President with stakeholders in the health sector. Maternal death reviews were only undertaken between 2015 and 2016 in four regions of Chad and ceased in mid-August 2016. Reasons include the departure of foreign obstetricians, lack of motivation among health workers, weak accountability at all levels of the health system, organizational issues, and nonimplementation of review recommendations., Conclusion: Strong action is needed by the Ministry of Health to revive implementation of the MDSR system., (© 2022 International Federation of Gynecology and Obstetrics.)

Background: Firearm head injuries cause great public health concern because of their severity. They are life-threatening due to intracranial lesions and sepsis risks. This prospective study evaluates the management of craniocerebral wounds in Chad., Methods: This is an observational study conducted over a period of 65 months with 44 patients with a ballistic craniocerebral wound (BCW), of which only 7.18% were assessed by neurosurgeons with gunshot wound., Results: The mean age was 30.57 ± 13 years (range:2-60 years). The 21-30 age group was the most affected (31.8%). The sex ratio was 21. A total of 63.6% of cases involved military personnel. The average admission time was 24.95 ± 12 hours (range: 1-72 hours). Explosive device attacks represented 29.5% of cases, of which 53.3% occurred in civilian practice. Point-blank shooting was reported in 70.5% of cases. The entry hole of the projectile was frontal in 40.9%. Intracranial sequestration of the projectile was found in 56.8%. Association of upper limb trauma was found in 9.1% of cases. Brain scans were performed in 95.5% of cases. Surgical treatment was undertaken in 68.18% of cases. The recovery process was marked by brain abscess in 6.8% of cases. Seven deaths were recorded., Conclusions: This study shows that BCW is frequent and mainly affects young male individuals in Chad. Many of the cases were related to improvised explosive device attacks, especially in civilian practice (70.5%). The delay in diagnostic and therapeutic management favors the high rate of sequelae., (Copyright © 2022 Elsevier Inc. All rights reserved.)

This report summarizes the status of the global Dracunculiasis Eradication Program as of the end of 2021. Dracunculiasis (Guinea worm disease) has been eliminated from 17 of 21 countries where it was endemic in 1986, when an estimated 3.5 million cases occurred worldwide. Only Chad, Ethiopia, Mali, and South Sudan reported cases in humans in 2021. Chad, Ethiopia, and Mali also reported indigenous infections of animals, mostly domestic dogs, with Dracunculus medinensis. Insecurity and infections in animals are the main obstacles remaining to interrupting dracunculiasis transmission completely.

We sequenced a portion of the E1 envelope protein gene of two of four CHIKV RT-PCR-positive samples from the first cluster of chikungunya patients during the 2020 Chad outbreak. Phylogenetic analysis revealed that the viruses belonged to the East/Central/South/African genotype but lacked the E1 A226V and K211E mutations associated with viral adaptability and transmission, suggesting an autochthonous transmission. These sequences are a useful basis for tracking viral evolution in subsequent outbreaks in Chad., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Objectives: Chad reports the second highest maternal mortality worldwide. We conducted a survey in Sila region in southeast Chad to estimate the use of maternal health services (MHS) and to identify barriers to access MHS., Design: Retrospective cross-sectional, population-based survey using two-stage cluster sampling methodology. The survey consisted of two strata, Koukou Angarana and Goz Beida district in Sila region. We conducted systematic random sampling proportional to population size to select settlements in each strata in the first sampling stage; and in the second stage we selected households in the settlements using random walk procedure. We calculated survey-design-weighted proportions with 95% CIs. We performed univariate analysis and multivariable logistic regression to identify impact factors associated with the use of MHS., Setting: We interviewed women in selected households in Sila region in 2019., Participants: Women at reproductive age, who have given birth in the previous 2 years and are living in Koukou Angarana and Goz Beida district., Primary Outcomes: Use of and access barriers to MHS including antenatal care (ANC), delivery care in a health facility (DC), postnatal care (PNC) and contraceptive methods., Results: In total, 624 women participated. Median age was 28 years, 95.4% were illiterate and 95.7% married. Use of ANC, DC and PNC was reported by 57.6% (95% CI: 49.3% to 65.5%), 22.5% (95% CI: 15.7% to 31.1%) and 32.9% (95% CI: 25.8% to 40.9%), respectively. Use of MHS was lower in rural compared with urban settings. Having attended ANC increased the odds of using DC by 4.3 (1.5-12.2) and using PNC by 6.4 (3.7-11.1). Factors related to transport and to culture and belief were the most frequently stated access barriers to MHS., Conclusion: In Sila region, use of MHS is low and does not meet WHO-defined standards regarding maternal health. Among all services, use of ANC was better than for other MHS. ANC usage is positively associated with the use of further life-saving MHS including DC and could be used as an entry point to the community. To increase use of MHS, interventions should include infrastructural improvements as well as community-based approaches to overcome access barriers related to culture and belief., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

There is currently a severe paucity of rural epidemiologic data on urogenital schistosomiasis in the Republic of Chad in north-central Africa that is hindering national control strategies. Our study describes a mobile medical team's 4-year effort to collect data and provide mass therapeutic and preventive chemotherapy in the Salamat Region of Chad, a previously uninvestigated rural area. To overcome severe limitations in time, resources, support, and infrastructure, the team employed several time- and cost-saving techniques that included: (1) traveling by request and referral to utilize local knowledge to find the areas of highest need, (2) conducting convenience sampling for screening, (3) using simple but validated tools to expedite treatment and data gathering, and (4) working within cultural contexts to find and treat the most school-age children possible. The team managed a total of 11,832 patient encounters and found a 55% rate of hematuria (n=6,495) among school-age children, roughly double previous estimates. Rates of hematuria were higher in males (61%, n=3,955/6,466) than females (48%, n=2,301/4,806) and among adolescents (> 65% in all age groups aged 10 years and older). These methods outline an efficient and effective strategy implemented under real-world conditions to enact therapeutic and preventive chemotherapy campaigns in resource-limited settings by engaging village leadership and developing locally driven solutions. Our data highlight the need for continued local epidemiologic efforts to treat the substantial number of children severely affected with schistosomiasis., (© Visclosky et al.)

Background: World Health Organization African region is wild poliovirus-free; however, outbreaks of vaccine-derived poliovirus type 2 (VDPV2) continue to expand across the continent including in Chad. We conducted a serological survey of polio antibodies in polio high-risk areas of Chad to assess population immunity against poliovirus and estimate the risk of future outbreaks., Methods: This was a community-based, cross-sectional survey carried out in September 2019. Children between 12 and 59 months were randomly selected using GIS enumeration of structures. Informed consent, demographic and anthropometric data, vaccination history, and blood spots were collected. Seropositivity against all 3 poliovirus serotypes was assessed using a microneutralization assay at Centers for Disease Control and Prevention, Atlanta, GA, USA., Results: Analyzable data were obtained from 236 out of 285 (82.8%) enrolled children. Seroprevalence of polio antibodies for serotypes 1, 2, and 3 was 214/236 (90.7%); 145/236 (61.4%); and 196/236 (86.2%), respectively. For serotype 2, the seroprevalence significantly increased with age (P = .004); chronic malnutrition was a significant risk factor for being type 2-seronegative., Interpretation: Poliovirus type 2 seroprevalence in young children was considered insufficient to protect against the spread of paralytic diseases caused by VDPV2. Indeed, VDPV2 outbreaks were reported from Chad in 2019 and 2020. High-quality immunization response to these outbreaks is needed to prevent further spread., (© The Author(s) 2021. Published by Oxford University Press on behalf of The Journal of the Pediatric Infectious Diseases Society.)

Introduction: Traditional treatment of limb trauma by traditional healers is ubiquitous in Sub-Saharan Africa. These practices are the source of many complications. This study aims to clarify the profile of these complications and to identify the factors favoring the consultation of traditional healers., Material and Methods: Descriptive and analytical study over 12 months, from February 1, 2018 to January 31, 2019, covering all the patients who consulted at the surgery department of the CHU Le Bon Samaritain in N'Djamena (CHUBS) for a complication of a fracture or dislocation of a limb treated by a traditional healer. Data collection was carried out using a pre-established questionnaire with an average follow-up of 14 months., Results: Out of 144 patients, 47 (33%) suffered from at least one complication of fracture or dislocation following traditional treatment. Thirty-two were included in the survey. Their mean age was 23 years (range 10-61) and the sex ratio 2.6 in favor of men. The origin was mainly rural: pupils/students and farmers/breeders were the most represented. We identified individuals from all levels of education, mainly primary level. Road accidents were the most frequent (n = 20). The influence of the entourage (n = 14) was the first factor leading to the choice of traditional treatment. The wooden splint, which did not immobilize the proximal fracture joints, associated with the ischemic bandage causing the gangrene, was the first means of restraint (n = 15). The mean time between trauma and the start of traditional treatment was 8.5 hours. The mean time from traditional treatment to onset of complications was 106 days (range 1-302). The most common complications were swelling of the limbs, malunions, gangrene and pseudarthrosis. The initial lesion was a closed fracture in most cases (n = 22) with a predominance of the pelvic limbs (n = 22). Hospital management was surgical (n = 19) or orthopedic (n = 13). Therapeutic progress has been good, fairly good or bad regarding 24, 2 and 6 cases respectively.The solicitation of traditional healers is frequent in traumatology. The influence of social background and ease of access to traditional "doctors" were noted as determining factors in the choice of this kind of treatment. The consequences of this practice have various origin: insufficient immobilization not respecting the standards; intense and untimely massages causing severe pain, secondary displacements and abnormal consolidation. Another study extended to patients who satisfied or not with the result of traditional fracture treatment in addition to those who consulted for complications would be more representative., Conclusion: The complications of traditional treatments for traumatic limb injuries are serious. The training of the traditional healers on basic notions of immobilization and the recognition of signs of seriousness, their collaboration with health structures as well as free care in hospital services would make possible to reduce this phenomenon. The media and social networks should help to reach a large audience., (Copyright © 2022 SFMTSI.)

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., Methods: we conducted a retrospective, descriptive study of patients with leprosy diagnosed between 2015 and 2019 at national level. Data were collected from the database of the National Program for the Control of Leprosy in Chad (NPCLC)., Results: a total of 1896 new cases of leprosy were detected in Chad between 2015 and 2019. The rates of patients aged 15 to 70 years and children under 15 years were 92.08% and 7.92% respectively. Sex ratio (M/F) was 1.68. The annual average detection rate was 2.6/100 000, with an average rate of multi-bacillary leprosy of 83.10% and degree 2 disability (2DD) of 20.38%. The average rate of degree 2 disability in children under 15 years of age was 0.92% . However, our study identified five districts as endemic (Adré, Abéché, Aboudeia, Koukou, et Bebedjia) in 2019, where the prevalence rate was above 1/10000 inhabitants., Conclusion: epidemiological trends are in favor of the persistence of the disease and a delay in diagnosis and in the management of leprosy cases., Competing Interests: Les auteurs ne déclarent aucun conflit d´intérêts., (Copyright: Abakar Kirga Kabo et al.)