Creating a framework towards integrated health syndromic surveillance and response in Africa

Background: A substantial part of the population in sub-Saharan Africa live in rural areas characterized by insufficiently equipped health centres and shortages of qualified health workers. These people usually depend on agriculture and livestock but have limited access to social services including health. In Chad, over 78% of the total population lives in rural areas and 3.5% are mobile pastoralists. Previous research has shown that agro-pastoralists suffer from a broad range of diseases of mostly unconfirmed biomedical aetiology. We propose a synergistic approach of integrated “One Health” surveillance-response combining epidemiology, anthropology and advanced biomedical diagnostic with essential complementary elements to anticipate outbreaks of endemic and emerging diseases from perceived illnesses (syndromes). Community-based syndromic surveillance, coupled with mobile technology adapted to the rural agro-pastoralists context, could offer an alternative to existing surveillance systems for humans and animals. Linking such a system with the etiologic confirmation of suspected cases from freshly collected samples would increase the potential of anticipating diseases outbreaks and leads to evidence-based and locally adapted interventions. Such participatory approach to surveillance and intervention could be further used for public and veterinary health service improvement along with zoonosis integration into existing digital and open source health information system application (DHIS2) aiming at their elimination. Aim and objectives: The aim of the thesis was to establish the basis of a culturally adapted and integrated community based human and animal health syndromic surveillance and response system among agro-pastoralists in Chad. We addressed intervention effectiveness, joint human and animal health interventions, zoonosis elimination and basic requirements for syndromic surveillance in remote rural communities using modern information and communication technology. The objectives of the thesis were to: 1. Contribute to health interventions effectiveness evaluation methods; 2. Evaluate One Health approaches (e.g. joint human and animal vaccination) among mobile communities and their potential for integration into the public health system; 3. Establish a basic knowledge on syndromic surveillance and response in order to implement a feasibility study of an integrated human and animal health surveillance and response system; and 4. Estimate the potential of zoonosis elimination in developing countries (the case of bovine tuberculosis in Morocco). Approach: Effectiveness of health interventions: Equity effectiveness of maternal health service coverage in rural Chad: Inequalities and large disparities in the burden of maternal morbidity and mortality still persist within and between different population groups mainly in low income countries. Policies need to be informed by equity sensitive evidence assessing differences in health needs and particularly in the effectiveness of interventions and models of care. The aim of this paper was to assess the community effectiveness of maternal health service coverage for sedentary and mobile populations in two rural districts in Chad. The approach allowed for quantifying the health system’s determinants of effectiveness. Our results provided a baseline to monitor the progress of a health system intervention in these districts focusing on maternal and infant health. Interventions should generally focus in priority on improving community effectiveness through targeting the factors with the highest leverage among specific populations in order to foster effective and equitable health services. Vaccine hesitancy among mobile communities in Chad: Demand side barriers for vaccination among rural and mobile populations in Chad are not yet well understood. We hypothesized that these mobile pastoralists’ communities face specific demand side barriers to access vaccination services. Understanding the factors that caregivers in these communities could take into account, explicitly or implicitly, in order to decide (or not) to vaccinate a child is an essential element to tailor vaccination programmes towards increasing vaccination acceptance and uptake. Our results showed that mobile pastoralist communities face specific demand side barriers to vaccination. Understanding these barriers is essential to reduce vaccine hesitancy and increase vaccination uptake. Local health systems must plan for periodic presence of pastoralist communities in their zones of responsibility and create more mutual trust. One Health methods and approaches: Feasibility and sustainability of joint human and animal vaccination: Joint human and animal vaccination programmes (JHAVP) such as “One Health” approaches have demonstrated to be feasible; to increase health care access to hard-to-reach communities; and to save resources through sharing transport, equipment and logistics in Chad. The main objective of the study was to give an insight to the feasibility and the sustainability of JHAVP integrated as part of the public health system in Chad. Our results showed that even though its integration as a routine activity at the district level depends on the mobilization of additional financial resources, the district could benefit from JHAVP to maintain a contact network with the nomads in order to promote the use of available immunization services at district level in the long term. Trends in health surveillance and service delivery for pastoralists in West and Central Africa: In most sub-Saharan African countries, pastoralism represents an important economic resource and contributes significantly to national growth; however, challenges remain, particularly in providing social services to pastoralists (especially health and education) and in avoiding conflict with local sedentary communities and local authorities. All of this takes place while pastoralists try to maintain their mobile lifestyle within a rapidly changing ecosystem. Although considerable efforts have been made towards integrating mobile pastoralists into social services, obstacles remain to the adoption of a clear, specific and sustainable policy on pastoralism in sub-Saharan Africa. Transmission dynamics and elimination potential of zoonotic tuberculosis in Morocco: A simple compartmental deterministic mathematical model for BTB transmission in cattle and humans have been established to provide a general understanding of BTB, in particular regarding transmission to humans. Differential equations were used to model the different pathways between the compartments for cattle and humans. Scenarios of test and slaughter were simulated to determine the effects of varying the proportion of tested animals (p) on the time to elimination of BTB (individual animal prevalence of less than one in a thousand) in cattle and humans and the economic cost due to elimination

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

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

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

Background:One Health approaches such as the Joint human and animal vaccination programmes (JHAVP) are shown to be feasible and to increase health care access to hard-to-reach communities such as mobile pastoralists. However, the financial sustainability and the integration into the public health systems at the district level of such programmes are still challenging. The main objective of the present study was to give insight to the feasibility and financial sustainability of JHAVP integrated as part of the public health system in Chad.Methods:We conducted a mixed methods study using semi-structured key informant interviews, focus group discussions and budget impact analysis. Strengths, weaknesses, opportunities, and threats were analysed regarding the feasibility and sustainability of the implementation of JHAVP in Danamadji health district in Chad. Feasibility was further analysed using three dimensions: acceptability, implementation, and adaptation. Financial sustainability of JHAVP was analysed through budget impact analysis of implementation of the programme at district level.Results:The acceptability of this approach was regularly assessed by immunization campaign teams through evalua-tion meetings which included pastoralists. The presence of authorities in the meetings and workshops of the pro-gramme had an incentive effect since they represent a mark of consideration these populations generally declared to be lacking. The coordination between the public health and veterinary services at central and decentralized level seemed to be a key element in the success of the implementation of the programme. Regarding financial sustainabil-ity, the total incremental budget impact was 27% slightly decreasing to 26% after five years, which accounts for up to one third of the total budget of the district health office. Also, given that most of the costs for each round are recur-rent costs, efficiency gains from scale effects over time are limited.Conclusion:Based on these findings, we conclude that for JHAVP to be routinely delivered at the district health level, a considerable increase in financial resources would be required. The district could benefit from joint immunization to maintain contact with mobile pastoralists to promote the use of available immunization services at district level

Prevalence and Diversity of Hepatitis Virus Markers among Patients with Acute Febrile Jaundice in Chad

peer reviewedOnly a minority of the patients with acute febrile jaundice evaluated through the Yellow Fever surveillance program were found positive for antibodies against Yellow Fever Virus (YFV). In order to characterize patients with acute febrile jaundice negative for YFV, we collected 255 sera between January to December 2019. We screened for HBV antigens, and antibodies against HCV and HEV. The seroprevalences observed were 10.6% (27/255) for HBV, 2% (5/255) for HCV, 17.3% (44/255) for HEV IgG, 4.3% (11/255) for HEV IgM, and 12.5% (32/255) for both IgG and IgM HEV. Prevalence of HEV was significantly higher in females than males (p < 0.01). HEV IgG prevalence was highest in those 20–29 years old, but the highest incidence rate (IgM positive) was in children 0–9 years old. Exposure to HEV was higher in the Sahelian zone (55.8%, 95%CI: 40.97–70.66) than in the Sudanese zone (30.2%, 95% CI: 24.01–36.37, p = 0.003). The high prevalence rates and hepatitis virus diversity underline the challenge of routine clinical diagnosis in Chad’s Yellow Fever surveillance program

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

Dogs play a major role in public health because of potential transmission of zoonotic diseases, such as rabies. Dog roaming behavior has been studied worldwide, including countries in Asia, Latin America, and Oceania, while studies on dog roaming behavior are lacking in Africa. Many of those studies investigated potential drivers for roaming, which could be used to refine disease control measures. However, it appears that results are often contradictory between countries, which could be caused by differences in study design or the influence of context-specific factors. Comparative studies on dog roaming behavior are needed to better understand domestic dog roaming behavior and address these discrepancies. The aim of this study was to investigate dog demography, management, and roaming behavior across four countries: Chad, Guatemala, Indonesia, and Uganda. We equipped 773 dogs with georeferenced contact sensors (106 in Chad, 303 in Guatemala, 217 in Indonesia, and 149 in Uganda) and interviewed the owners to collect information about the dog [e.g., sex, age, body condition score (BCS)] and its management (e.g., role of the dog, origin of the dog, owner-mediated transportation, confinement, vaccination, and feeding practices). Dog home range was computed using the biased random bridge method, and the core and extended home range sizes were considered. Using an AIC-based approach to select variables, country-specific linear models were developed to identify potential predictors for roaming. We highlighted similarities and differences in term of demography, dog management, and roaming behavior between countries. The median of the core home range size was 0.30 ha (95% range: 0.17–0.92 ha) in Chad, 0.33 ha (0.17–1.1 ha) in Guatemala, 0.30 ha (0.20–0.61 ha) in Indonesia, and 0.25 ha (0.15–0.72 ha) in Uganda. The median of the extended home range size was 7.7 ha (95% range: 1.1–103 ha) in Chad, 5.7 ha (1.5–27.5 ha) in Guatemala, 5.6 ha (1.6–26.5 ha) in Indonesia, and 5.7 ha (1.3–19.1 ha) in Uganda. Factors having a significant impact on the home range size in some of the countries included being male dog (positively), being younger than one year (negatively), being older than 6 years (negatively), having a low or a high BCS (negatively), being a hunting dog (positively), being a shepherd dog (positively), and time when the dog was not supervised or restricted (positively). However, the same outcome could have an impact in a country and no impact in another. We suggest that dog roaming behavior is complex and is closely related to the owner's socioeconomic context and transportation habits and the local environment. Free-roaming domestic dogs are not completely under human control but, contrary to wildlife, they strongly depend upon humans. This particular dog–human bound has to be better understood to explain their behavior and deal with free-roaming domestic dogs related issues

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

Influenza-like Illness (ILI) is a medical diagnosis of possible influenza or another respiratory illness with a common set of symptoms. The deaths of four schoolchildren, during a pandemic influenza outbreak in December 2017 in Ghana, raised doubts about the ILI surveillance system's performance. We evaluated the ILI surveillance system in the Greater Accra region, Ghana, to assess the system's attributes and its performance on set objectives.; CDC guidelines were used to evaluate the data of the ILI surveillance system between 2013 and 2017. We interviewed the surveillance personnel on the system's description and operation. Additionally, routinely entered ILI data from the National Influenza Center provided by the six sentinel sites in Accra was extracted. We sampled and reviewed 120 ILI case-investigation forms from these sites. Surveillance activities were examined on system's performance indicators, each being scored on a scale of 1 to 3 (poorest to best performance).; All population and age groups were under ILI surveillance over the period evaluated. Overall, 2948 suspected case-patients, including 392 (13.3%) children under-five were reported, with 219 being positive for influenza virus (Predictive value positive = 7.4%). The predominant influenza subtype was H3N2, recorded in 90 (41.1%) of positive case-patients. The system only met two out of its four objectives. None of the six sentinel sites consistently met their annual 260 suspected case-detection quota. Samples reached the laboratory on average 48 hours after collection and results were disseminated within 7 days. Of 120 case-investigation forms sampled, 91 (76.3%) were completely filled in.; The ILI surveillance system in the Greater Accra region is only partially meeting its objectives. While it is found to be sensitive, representative and timely, the data quality was sub-optimal. We recommend the determination of thresholds for alert and outbreak detection and ensuring that sentinel sites meet their weekly case-detection targets

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

To assess antenatal care (ANC) coverage and analyse constraining factors for service delivery to rural settled and mobile populations in two districts in Chad.; Data from cross-sectional household and health facility surveys in the two Chadian rural health districts were analysed. First, contact coverage of ANC services in the study area was estimated from household data as the proportion of women who visited health facilities to obtain ANC during their last pregnancy. Second, bottlenecks in the provision of this service were explored by calibrating a multiplicative model of ANC contact coverage to household and health facility data. The model allowed quantification of the magnitude by which coverage decreased as it progressed through the health system. Sensitivity analysis was applied to account for uncertainty around the estimated coverage factors.; Direct estimates revealed that ANC contact coverage decreased as the number of required visits increased: 79% of rural settled mothers and 46% of mobile pastoralist mothers visited a health facility to obtain ANC at least once (ANC 1). Among mobile pastoralists, only 20% of pregnant women attended ANC at least three times compared to 63% of rural settled women. Availability, accessibility, affordability and acceptability contributed to reductions in service coverage in both populations. For mobile pastoralists, acceptability was clearly the most important factor. ANC 1 contact coverage resulting from the model is 50% for rural settled and 30% for mobile pastoralists.; Antenatal care coverage was low in rural districts of Chad, particularly for mobile pastoralists. Acceptability largely explained the prevailing difference between the two population groups

Seroprevalence of rift valley fever, Q fever, and brucellosis in ruminants on the southeastern shore of lake Chad

Abstract The seroprevalence of Rift Valley fever (RVF), brucellosis, and Q fever among domestic ruminants on the southeastern shore of Lake Chad was studied. The study area consisted of two parts, including mainland and islands. On the mainland, the study was conducted in nine randomly selected villages and camps. On the islands, samples were collected from all four available sites. A total of 985 serum samples were collected and 924 were analyzed using enzyme-linked immunosorbent assay (ELISA) for RVF. A total of 561 samples collected from islands were analyzed using ELISA for Q fever and both ELISA and Rose Bengal tests (RBT) for brucellosis. The apparent RVF seroprevalence by species was 37.8% (95% confidence interval [CI] 34.2-41.3) in cattle, 18.8% (95% CI 12.3-25.2) in goats, and 10.8% (95% CI 3.0-18.5) in sheep. For brucellosis and Q fever, only cattle samples from islands were analyzed. For Q fever, the apparent seroprevalence was 7.8% (95% CI 5.6-10.1). For brucellosis, the RBT showed a prevalence of 5.7% (95% CI 3.8-7.6), and ELISA showed 11.9% (95% CI 9.3-14.6) with a kappa value of 0.53 showing a moderate agreement between the two tests. This study confirms the presence of the three diseases in the study area. More research is required to assess the importance for public health and conservation of the Kouri cattle breed

Vaccine hesitancy among mobile pastoralists in Chad: a qualitative study

Abstract Background Demand side barriers to vaccination among rural and hard-to-reach populations in Chad are not yet well understood. Although innovative approaches such as linking human and animal vaccination increase vaccination uptake among mobile pastoralist communities, vaccination coverage in these communities is still lower than for rural settled populations. We hypothesize that mobile pastoralists’ communities in Chad face specific demand side barriers to access vaccination services. Understanding the factors that caregivers in these communities consider, explicitly or implicitly, in order to decide whether or not to vaccinate a child, in addition to understanding the provider’s perspectives, are essential elements to tailor vaccination programmes towards increasing vaccination acceptance and uptake. Methods We conducted a qualitative study in a rural health district in southern Chad in April 2016 with 12 key informant in-depth interviews and four focus group discussions (FGDs) including 35 male and female participants. Participants in the study included caregivers, traditional chiefs, local and religious leaders from mobile pastoralist communities, and health officials and staff. We conducted a content analysis using a pre-defined set of categories for vaccine hesitancy covering issues on harmful effects of vaccination, mistrust with vaccination programmes/services, issues with the health system and other issues. Results The groups of demand side barriers reported most frequently in focus group discussions were mistrust on the expanded programme on immunization (EPI) and polio vaccination outreach services (53%, n = 94), followed by health system issues (34%, n = 94), and concerns related to potential harm of vaccines (13%, n = 94). Concerns identified by caregivers, health professionals and community leaders followed a similar pattern with issues on programme mistrust being most frequently reported and issues with harm least frequently reported. None of the health professionals reported concerns about vaccinations being potentially harmful. Conclusion Mobile pastoralist communities face specific demand side barriers to vaccination. Understanding these barriers is essential to reduce vaccine hesitancy and increase vaccination uptake. Local health systems must plan for the periodic presence of pastoralist communities in their zones of responsibility and create more mutual trust