Epidemiology of group A rotavirus in children under five years of age with gastroenteritis in N'Djamena, Chad.

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.

Surveillance of tick-borne pathogens in domestic dogs from Chad, Africa.

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.

Contextual factors for understanding the heterogeneity of outcomes of a policy of exemption from payment for care in Chad / Les facteurs contextuels pour comprendre l'hétérogénéité des résultats d'une politique d'exemption du paiement des soins au Tchad

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.

Le Tchad a l'un des taux de mortalité maternelle et infantile les plus élevés au monde. Les efforts visant à réduire ces taux ont conduit à la mise en place d'une politique d'exemption du paiement des soins, associée à l'implication des communautés pour encourager l'utilisation des services. Malgré l'introduction de cette initiative, des inégalités dans l'accès et l'utilisation des établissements de santé persistent. L'objectif de cette étude est de comprendre pourquoi et comment cette politique d'exemption, mise en œuvre de manière quasi homogène, a donné des résultats contrastés dans plusieurs centres de santé. Une étude de cas multiples contrastés a été utilisée pour analyser les résultats des consultations pédiatriques et des accouchements dans quatre centres de santé des districts de Bénoye et Beinamar. Les données ont été recueillies lors des entretiens individuels (n=26) et des groupes de discussion (n=22) auprès des femmes bénéficiaires, des agents de santé communautaire et des prestataires de soins. Le logiciel QDA Miner a été utilisé pour traiter les données. L'étude a révélé que les capacités organisationnelles et managériales des prestataires et des acteurs communautaires expliqueraient l'hétérogénéité des résultats observés. Des facteurs contextuels tels que l'éloignement des services ou l'impraticabilité et la dangerosité des routes ont accentué les disparités des résultats observés. Dans la mise en place des politiques de santé, il est important de tenir compte des facteurs humains et contextuels, car ils participent à l'explication de l'hétérogénéité des effets observés et renforcent la pertinence de ce type d'études.

Women's autonomy and fertility in Chad.

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.

Au Tchad, l'Indice Synthétique de Fécondité (ISF) est de 6,4 enfants par femme, alors que chez ses voisins, comme le Cameroun et la RCA, il ne dépasse pas 5,5. Il est alors très important de réaliser des recherches scientifiques sur les déterminants de la fécondité dans le premier pays, afin de montrer à ses décideurs comment ils devraient renforcer leurs actions dans ce domaine. La recherche réalisée ici en est un exemple et porte spécifiquement sur l'influence de l'autonomie de la femme sur sa fécondité dans ce pays. Les analyses des données de l'Enquête Démographique et de Santé et à Indicateurs Multiples (EDS/MICS) qui y a été menée en 2014/2015, et de celles de l'enquête qualitative, menée dans le même pays en 2020, ont, entre autres, révélé, ce qui suit : 1) dans les groupes socioculturels très inégalitaires en matière de genre, l'autonomie de la femme est positivement associée à sa fécondité désirée ; 2) dans ces groupes et dans ceux moins inégalitaires, toutes choses égales par ailleurs, l'autonomie de la femme est associée négativement à sa fécondité effective ; 3) les hypothèses d'explication de cette relation varie selon les groupes socioculturels : dans les premiers, les décès fréquents d'enfants entraînent les couples où les femmes ont une autonomie nulle ou faible à les compenser par une fécondité élevée ; dans les derniers, ce sont les entrées tardives en union, les ruptures d'unions, les effets réducteurs d'allaitement et de la contraception moderne et d'autres variables intermédiaires de la fécondité, non prises en compte, qui justifient pourquoi l'autonomie de la femme y est négativement associée à sa fécondité. Les résultats de cette étude témoignent non seulement de la pertinence des programmes de développement focalisés dans ce pays sur l'autonomisation de la femme, mais aussi du fait que pour être efficaces ces programmes devraient prendre suffisamment en compte les contextes dans lesquels vivent les populations concernées.

Molecular characterization of chikungunya virus from the first cluster of patients during the 2020 outbreak in Chad.

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.

Spatial and multilevel analysis of unskilled birth attendance in Chad.

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.

A mathematical model of Guinea worm disease in Chad with fish as intermediate transport hosts.

Guinea-worm disease (GWD) was thought to be almost eliminated in Chad when it reemerged in 2010. The disease now shows a peculiar pattern of spreading along Chari River and its tributaries, rather than clustering around a particular drinking water source. We create a mathematical model of GWD that includes the population dynamics of the parasite as well as the dynamics of its hosts (copepods, fish, humans, and domestic dogs). We calibrate our model based on data from the literature and validate it on the recent GWD annual incidence data from Chad. The effective reproduction number predicted by our model agrees well with the empirical value of roughly 1.25 derived directly from the data. Our model thus supports the hypothesis that the parasite now uses fish as intermediate transport hosts. We predict that GWD transmission can be most easily interrupted by avoiding eating uncooked fish and by burying the fish entrails to prevent transmission through dogs. Increasing the mortality of copepods and even partially containing infected dogs to limit their access to water sources is another important factor for GWD eradication.

Primary resistance to antiretroviral drugs of HIV strains in Chad: a retrospective investigation by analysis of frozen dried blood spot samples.

No data concerning antiretroviral drug's (ARV) primary resistance mutation rates in Chad are available. We retrospectively analysed frozen-stored dried blood spot samples that were collected from 48 Chadian human immunodeficiency virus (HIV)-1 seropositive patients naïve of ARV. HIV-1 protease and reverse transcriptase genes were successfully sequenced for 24 (60.0%) of the 40 patients displaying a viral load > 1000 copies/ml. Seven (29.2%) displayed mutations conferring resistance against one or more classes of ARV. We evidenced high levels of primary ARV resistance mutations in Chad, but lower than those observed in patients with failure to first-line ARV.

Factors associated with female genital mutilation among women of reproductive age and girls aged 0-14 in Chad: a mixed-effects multilevel analysis of the 2014-2015 Chad demographic and health survey data.

BACKGROUND: Chad is one of the African countries with high prevalence of female genital mutilation (FGM). The aim of this study was to examine the factors associated with FGM among women aged 15-49 and girls aged 0-14 in Chad. METHODS: Data for the study were obtained from the 2014-2015 Chad Demographic and Health Survey. FGM among women aged 15-49 and girls aged 0-14 were the outcome variables. The prevalence of FGM among women and girls were presented using percentages while a mixed-effects multilevel multivariable logistic regression analysis was carried out to assess the factors associated with FGM. The results were presented using adjusted odds ratio with associated 95% confidence intervals. RESULTS: The results indicate that more than half (50.2%) of the women and 12.9% of girls in Chad had been circumcised. Among women aged 15-49, level of education, employment status, ethnicity, religion, wealth quintile and community literacy level were significant predictors of FGM. Age, partner's level of education, marital status, employment status, ethnicity, religion and mother's FGM status were associated with FGM among girls aged 0-14. CONCLUSION: This study has identified several individual and contextual factors as predictors of FGM among women and girls in Chad. The findings imply the need to adopt strategies aimed at addressing these factors in order to help eliminate the practice of FGM. Government and non-governmental organisations in Chad need to implement policies that enhance media advocacy and community dialogue to help deal with FGM in the country.

Knowledge, Attitudes and Practices Regarding COVID­19 in N'Djamena, Chad.

The first African COVID-19 case was reported in Egypt in February 2020. Since then, Sub-Saharan countries have struggled to respond to the pandemic. Among them, Chad is characterized by a high rate of poverty and mortality, a high burden of infectious diseases, insufficient epidemiological surveillance and underdeveloped infrastructure. In this study, we explore the knowledge, attitudes and practices (KAPs) regarding COVID-19 within the Chadian population, to determine whether there are more vulnerable groups of the population that require greater attention from authorities. This study was designed as a cross-sectional survey conducted in N'Djamena, Chad, using a convenience sampling technique that included 2269 participants. The study was conducted in May and August 2020. Questions regarding technical concepts were answered incorrectly by most participants (83.65%). The population had better knowledge about concrete aspects of the pandemics, such as prevention measures and contagion. Regarding attitudes, 34.55% participants were very concerned about the possibility of being infected, 81.27% were unsatisfied/very unsatisfied with their social relationships after the pandemic began, and 68.44% thought that the pandemic was a disturbing/very disturbing issue. As for practices, 49.41% of men followed all preventive measures compared to 32.07% of women, and 3.04% of people with vulnerable jobs did not respect any of preventive measures compared to 1.19% of people without this condition. Gender, job conditions and educational level impact KAPs within the Chadian population. It is suggested that local authorities in Chad should consider these variables when developing health strategies.

Health management information system (HMIS) data quality and associated factors in Massaguet district, Chad.

BACKGROUND: Quality data from Health Management Information Systems (HMIS) are important for tracking the effectiveness of malaria control interventions. However, HMIS data in many resource-limited settings do not currently meet standards set by the World Health Organization (WHO). We aimed to assess HMIS data quality and associated factors in Chad. METHODS: A cross-sectional study was conducted in 14 health facilities in Massaguet district. Data on children under 15 years were obtained from the HMIS and from the external patient register covering the period January-December 2018. An additional questionnaire was administered to 16 health centre managers to collect data on contextual variables. Patient registry data were aggregated and compared with the HMIS database at district and health centre level. Completeness and accuracy indicators were calculated as per WHO guidelines. Multivariate logistic regressions were performed on the Verification Factor for attendance, suspected and confirmed malaria cases for three age groups (1 to < 12 months, 1 to < 5 years and 5 to < 15 years) to identify associations between health centre characteristics and data accuracy. RESULTS: Health centres achieved a high level of data completeness in HMIS. Malaria data were over-reported in HMIS for children aged under 15 years. There was an association between workload and higher odds of inaccuracy in reporting of attendance among children aged 1 to < 5 years (Odds ratio [OR]: 10.57, 95% CI 2.32-48.19) and 5- < 15 years (OR: 6.64, 95% CI 1.38-32.04). Similar association was found between workload and stock-outs in register books, and inaccuracy in reporting of malaria confirmed cases. Meanwhile, we found that presence of a health technician, and of dedicated staff for data management, were associated with lower inaccuracy in reporting of clinic attendance in children aged under five years. CONCLUSION: Data completeness was high while the accuracy was low. Factors associated with data inaccuracy included high workload and the unavailability of required data collection tools. The results suggest that improvement in working conditions for clinic personnel may improve HMIS data quality. Upgrading from paper-based forms to a web-based HMIS may provide a solution for improving data accuracy and its utility for future evaluations of health interventions. Results from this study can inform the Ministry of Health and it partners on the precautions to be taken in the use of HMIS data and inform initiatives for improving its quality.

[Improving provision of mother-and-child care in Chad at the community level: A quasi-experimental study]. / Amélioration de l'offre et de la demande de soins de santé maternelle et infantile au Tchad : une étude quasi-expérimentale.

BACKGROUND: Chad is among the countries with the highest maternal and infant mortality rates in the world. An initiative aimed at improving mother-and-child health services was implemented from 2016 to 2019 in three rural health districts in southern Chad, with strong community input, while concomitantly increasing the supply and demand for care. The objective of this study is to evaluate the effects of this program on health service use. METHODS: Interrupted time-series analyses with a control group was used to measure the effects of the intervention by applying a quasi-experimental approach. Monthly attendance data were collected from the registries of the 18 health centres that participated in the program and 18 centres that did not participate (control group), before (18 months) and after (24 months) the start of implementation. RESULTS: On average, there were 10.98 (95% CI: 6.57-15.39, P<0.001) additional paediatric visits and 0.68 additional deliveries (95% CI: 0.42-0.95, P<0.001) each month in the participation group compared to the control group. Community involvement decisively contributed to the change. CONCLUSION: During the 24 months of implementation, the initiative significantly increased the use of essential mother-and-child health services in Chad. This study highlights the benefits of a strong partnership with communities trained and involved in health system activities, with the objective of achieving universal health coverage.

Does community-wide water chlorination reduce hepatitis E virus infections during an outbreak? A geospatial analysis of data from an outbreak in Am Timan, Chad (2016-2017).

Hepatitis E Virus (HEV) genotype 1 and 2 infect an estimated 20 million people each year, via the faecal-oral transmission route. An urban outbreak of HEV occurred in Am Timan, Chad, between September 2016 and April 2017. As part of the outbreak response, Médecins Sans Frontières and the Ministry of Health implemented water and hygiene interventions, including the chlorination of town water sources. We aimed to understand whether these water treatment activities had any impact on the number of HEV infections, using geospatial analysis of epidemiological and water treatment monitoring data. By conducting cluster analysis we investigated whether there were areas of particularly high and low infection risk during the outbreak and explored the reasons for this. We observed two high-risk spatial clusters of suspected cases and one high-risk cluster of confirmed cases. Our main finding was that confirmed HEV cases had a higher median number of days of exposure to unsafe water compared to suspected and non-confirmed cases (Kruskal-Wallis Chi Square: 15.5; p < 0.001). Our study confirms the mixed, but shifting, transmission routes during this outbreak. It also highlights the spatial and temporal analytical methods, which can be employed in future outbreaks to improve understanding of HEV transmission.

Proximate, intermediate, and distal predictors of under-five mortality in Chad: analysis of the 2014-15 Chad demographic and health survey data.

BACKGROUND: Under-five mortality in Chad reached a minimum value of 119 deaths per 1000 live births in 2018, compared with a maximum of 250 in 1972. Despite this decline in the  mortality trend, for every six children in Chad, one dies before the age of five. This study, therefore, investigated the proximate, intermediate, and distal determinants of under-five mortality in Chad. METHODS: We used data from the 2014-15 Chad's Demographic and Health Survey. Data of 7782 children below 5 years were used for the study. Both descriptive and multivariable hierarchical logistic regression analyses were performed. Statistical significance was declared at p < 0.05. RESULTS: Under-five mortality was found to be 130 deaths per 1000 live births in Chad, with variations across the various population sub-groups. For distal predictors, the likelihood of death was higher in children born in the FChari Baguirmi region (AOR = 3.83, 95% CI: 1.81-8.14). Children whose mothers belonged to the Baguirmi/Barma ethnic group (AOR = 8.04, 95% CI: 1.75-36.99) were more likely to die before the age of five. On the contrary, the likelihood of under-five mortality was low among children born in rural areas (AOR = 0.73, 95% CI: 0.55-0.97). With the intermediate predictors, the likelihood of under-five deaths was higher among children whose mothers had no formal education (AOR = 1.72, 95% CI: 1.06-2.77). Regarding the proximate predictors, the odds of under-five deaths was higher among male children (AOR = 1.03, 95% CI: 1.05-1.63) and first rank children (AOR = 1.58, 95% CI: 1.13-2.21). CONCLUSION: The study found that the determinants of under-five mortality in Chad are region of residence, place of residence, ethnicity, education, sex of child, and birth rank. These findings show that both socio-economic and proximate factors explain the disparities in under-five mortality in Chad. The identification of these factors can be pivotal towards the design of evidence-based interventions intended to improve child survival. Therefore, improving maternal education while refocusing and re-packaging existing strategies to target selected sub-regional populations with high under-five mortality is urgently required.

The State of Maternal and Infant Health and Mortality in Chad.

The level of Chad's government expenditure on health is a predictor of the general health of the population and, consequently, life expectancy. We used data from the World Bank's World Development Indicators and publications from the World Health Organization to assess the state of maternal and infant health and mortality. The primary objective of this research was to investigate whether Chad had reduced the risk of maternal and infant mortality after signing the Abuja Declaration in 2001. We hypothesised that increased general government health expenditure was associated with improved health mediated by increased numbers of skill health workers and minimum out-of-pocket health expenditure. Our secondary objective was to assess effective implementations of health policies in line with the Millennium Development Goals that Chad has agreed to achieve by 2015. We observed that, as of 2015, the government health expenditure was only 6.28% and the population out-of-pocket spending was over 56%. Furthermore, only 20% of women give birth in a hospital. These results led to three major policies recommendations in order to improve maternal and infant health in Chad: skilled birth attendants training, enhanced social status of nurses, and the development of a supplemental nutrition care program for women.

Implementation of Case-Based Surveillance and Real-time Polymerase Chain Reaction to Monitor Bacterial Meningitis Pathogens in Chad.

BACKGROUND: Meningococcal serogroup A conjugate vaccine (MACV) was introduced in Chad during 2011-2012. Meningitis surveillance has been conducted nationwide since 2003, with case-based surveillance (CBS) in select districts from 2012. In 2016, the MenAfriNet consortium supported Chad to implement CBS in 4 additional districts and real-time polymerase chain reaction (rt-PCR) at the national reference laboratory (NRL) to improve pathogen detection. We describe analysis of bacterial meningitis cases during 3 periods: pre-MACV (2010-2012), pre-MenAfriNet (2013-2015), and post-MenAfriNet (2016-2018). METHODS: National surveillance targeted meningitis cases caused by Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae. Cerebrospinal fluid specimens, inoculated trans-isolate media, and/or isolates from suspected meningitis cases were tested via culture, latex, and/or rt-PCR; confirmed bacterial meningitis was defined by a positive result on any test. We calculated proportion of suspected cases with a specimen received by period, and proportion of specimens with a bacterial meningitis pathogen identified, by period, pathogen, and test. RESULTS: The NRL received specimens for 6.8% (876/12813), 46.4% (316/681), and 79.1% (787/995) of suspected meningitis cases in 2010-2012, 2013-2015, and 2016-2018, respectively, with a bacterial meningitis pathogen detected in 33.6% (294/876), 27.8% (88/316), and 33.2% (261/787) of tested specimens. The number of N. meningitidis serogroup A (NmA) among confirmed bacterial meningitis cases decreased from 254 (86.4%) during 2010-2012 to 2 (2.3%) during 2013-2015, with zero NmA cases detected after 2014. In contrast, proportional and absolute increases were seen between 2010-2012, 2013-2015, and 2016-2018 in cases caused by S. pneumoniae (5.1% [15/294], 65.9% [58/88], and 52.1% [136/261]), NmX (0.7% [2/294], 1.1% [1/88], and 22.2% [58/261]), and Hib (0.3% [1/294], 11.4% [10/88], and 14.9% [39/261]). Of specimens received at the NRL, proportions tested during the 3 periods were 47.7% (418), 53.2% (168), and 9.0% (71) by latex; 81.4% (713), 98.4% (311), and 93.9% (739) by culture; and 0.0% (0), 0.0% (0), and 90.5% (712) by rt-PCR, respectively. During the post-MenAfriNet period (2016-2018), 86.1% (678) of confirmed cases were tested by both culture and rt-PCR, with 12.5% (85) and 32.4% (220) positive by culture and rt-PCR, respectively. CONCLUSIONS: CBS implementation was associated with increased specimen referral. Increased detection of non-NmA cases could reflect changes in incidence or increased sensitivity of case detection with rt-PCR. Continued surveillance with the use of rt-PCR to monitor changing epidemiology could inform the development of effective vaccination strategies.

High prevalence and characterization of extended-spectrum ß-lactamase producing Enterobacteriaceae in Chadian hospitals.

BACKGROUND: Extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-PE) represent a major problem in the management of nosocomial infections. However, ESBL-PE are not systematically monitored in African countries. The aim of this study was to determine ESBL-PE prevalence in patients from three hospitals in N'Djamena, the capital city of Chad, and to characterize the genetic origin of the observed resistance. METHODS: From January to March 2017, 313 non-duplicate isolates were recovered from various clinical specimens obtained from 1713 patients in the three main hospitals of N'Djamena. Bacterial species were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Susceptibility to 28 antibiotics was tested using the disk diffusion method on Müller-Hinton agar, and ESBL production was confirmed with the double-disc synergy test. The most prevalent ESBL genes associated with the observed resistance were detected using multiplex PCR followed by double-stranded DNA sequencing. RESULTS: Among the 313 isolates, 197 belonged to the Enterobacteriaceae family. The overall ESBL-PE prevalence was 47.72% (n = 94/197), with a higher rate among inpatients compared with outpatients (54.13% vs. 34.37%). ESBL-PE prevalence was highest in older patients (≥60 years of age). E. coli was the most common ESBL-producer organism (63.8%), followed by K. pneumoniae (21.2%). ESBL-PE were mainly found in urine samples (75%). The CTX-M-1 group was dominant (96.7% of the 94 ESBL-PE isolates, CTX-M-15 enzyme), followed by the CTX-M-9 group (4.1%). 86% of resistant isolates harbored more than one ESBL-encoding gene. ESBL production was also associated with the highest levels of resistance to non-ß-lactam drugs. CONCLUSIONS: The prevalence of ESBL-PE harboring resistant genes encoding ESBLs of the CTX-M-1 group was high (48%) among clinical isolates of three main hospitals in Chad, suggesting an alarming spread of ESBL-PE among patients.

Dracunculiasis: water-borne anthroponosis vs. food-borne zoonosis.

Dracunculiasis is the first parasitic disease set for eradication. However, recent events related to the Dracunculus medinensis epidemiology in certain African countries are apparently posing new challenges to its eradication. Two novel facts have emerged: the existence of animal reservoirs (mainly dogs but also cats and baboons), and possibly a new food-borne route of transmission by the ingestion of paratenic (frogs) or transport (fish) hosts. Therefore, instead of being exclusively a water-borne anthroponosis, dracunculiasis would also be a food-borne zoonosis. The existence of a large number of infected dogs, mainly in Chad, and the low number of infected humans, have given rise to this potential food-borne transmission. This novel route would concern not only reservoirs, but also humans. However, only animals seem to be affected. Dracunculus medinensis is on the verge of eradication due to the control measures which, classically, have been exclusively aimed at the water-borne route. Therefore, food-borne transmission is probably of secondary importance, at least in humans. In Chad, reservoirs would become infected through the water-borne route, mainly in the dry season when rivers recede, and smaller accessible ponds, with a lower water level containing the infected copepods, appear, whilst humans drink filtered water and, thus, avoid infection. The total absence of control measures aimed at dogs (or at other potential reservoirs) up until the last years, added to the stimulating reward in cash given to those who find parasitized dogs, have presumably given rise to the current dracunculiasis scenario in Chad.