Rabies control in N'Djamena, Chad

Rabies is a viral disease that induces invariably fatal encephalitis. Most affected by the disease are resource poor countries. Worldwide burden estimates reveal that the disease claims about one human victim every ten minutes. Transmission of the virus to humans occurs in over 95% through a bite of an infected dog. The only method for sustainable control of canine rabies and elimination at the source is dog vaccination. Since the year 2000 Swiss TPH works in close partnership with the Institut de Recherche en Élevage pour le Développement (IRED) and the Centre de Support en Santé Internationale (CSSI) on the control of rabies in N’Djaména, the capital city of Chad. The project phase from 2012-2015 has led to my doctoral thesis, which spans over many aspects of rabies control. Two mass vaccination campaigns have been conducted in 2012 and 2013 that covered the whole town and reached consecutively over 70% of the canine population. The intervention led to a drastic drop of dog rabies incidence. Data on animal rabies incidence, bite exposure incidence and Post-Exposure Prophylaxis (PEP) demand were used to validate a dog to human transmission model and to update the cost-effectiveness analysis of dog vaccination. The thesis also includes the validation of a rapid, simple rabies diagnostic test that has the potential to enhance surveillance in resource poor settings. On the national level economic aspects of a countrywide control program, a dog demographic survey and a Knowledge Attitude and Practices (KAP) study among the Chadian population are presented. Finally, social determinants of accessibility and effectiveness of rabies vaccination campaigns are discussed, by comparing the results from N’Djamena with a similar study in Bamako, Mali

La danse à l’école primaire :: quelle place ? pour quelles raisons ? quels effets sur les stéréotypes de genre ?

Ce travail de mémoire est né inconsciemment de ma période de scolarité obligatoire pour apparaître ensuite comme une évidence dans le cadre de mon cursus en enseignement. Cette recherche vise ainsi à questionner la place attribuée à la danse en milieu scolaire et à en comprendre les enjeux. Ayant constaté qu'elle est encore aujourd’hui une discipline stéréotypée, ce thème est également abordé à travers ce travail. De plus, celui-ci traite de la dualité art/sport de la danse. Ainsi, les trois composantes émergeant de la problématique sont donc la danse, les stéréotypes de genre et l’école. Pour approcher ces deux premières thématiques, une définition de chacune est donnée, suivie d’un éclairage sur leurs places respectives dans le milieu scolaire. Par le biais d’un questionnaire et d’entretiens semi-directifs, j’ai souhaité apporter quelques éléments d’explication aux constats sur la place de la danse et des stéréotypes de genre à l’école primaire. Sont également récoltés quelques concepts et recommandations quant à l’enseignement futur de la danse. Après analyse, il s’avère que les stéréotypes de genre ne sont pas le principal frein à cet enseignement, mais qu’un manque de connaissance et d’outils conséquent en est un pour une majorité d’enseignants

Validation of a Rapid Rabies Diagnostic Tool for Field Surveillance in Developing Countries

One root cause of the neglect of rabies is the lack of adequate diagnostic tests in the context of low income countries. A rapid, performance friendly and low cost method to detect rabies virus (RABV) in brain samples will contribute positively to surveillance and consequently to accurate data reporting, which is presently missing in the majority of rabies endemic countries.; We evaluated a rapid immunodiagnostic test (RIDT) in comparison with the standard fluorescent antibody test (FAT) and confirmed the detection of the viral RNA by real time reverse transcription polymerase chain reaction (RT-qPCR). Our analysis is a multicentre approach to validate the performance of the RIDT in both a field laboratory (N'Djamena, Chad) and an international reference laboratory (Institut Pasteur, Paris, France). In the field laboratory, 48 samples from dogs were tested and in the reference laboratory setting, a total of 73 samples was tested, representing a wide diversity of RABV in terms of animal species tested (13 different species), geographical origin of isolates with special emphasis on Africa, and different phylogenetic clades. Under reference laboratory conditions, specificity was 93.3% and sensitivity was 95.3% compared to the gold standard FAT test. Under field laboratory conditions, the RIDT yielded a higher reliability than the FAT test particularly on fresh and decomposed samples. Viral RNA was later extracted directly from the test filter paper and further used successfully for sequencing and genotyping.; The RIDT shows excellent performance qualities both in regard to user friendliness and reliability of the result. In addition, the test cassettes can be used as a vehicle to ship viral RNA to reference laboratories for further laboratory confirmation of the diagnosis and for epidemiological investigations using nucleotide sequencing. The potential for satisfactory use in remote locations is therefore very high to improve the global knowledge of rabies epidemiology. However, we suggest some changes to the protocol, as well as careful further validation, before promotion and wider use

Rabies immunoglobulin: brief history and recent experiences in Côte D'Ivoire

Rabies is a fatal viral zoonosis mainly transmitted via dog bites. The estimated 59'000 annual deaths caused by the disease are preventable through correct and timely administration of post-exposure prophylaxis (PEP). PEP should be initiated as soon as possible after an exposure to a rabies suspected animal and consists of a course of active vaccinations and administration of rabies immunoglobulin (RIG) in case of severe exposure. However, RIG is not accessible in most rabies endemic countries and its impact on survival in combination with modern vaccines and its cost-effectiveness is unclear. We examined the effect of equine RIG (eRIG) in a field-trial in Côte d'Ivoire, a developing country with low but chronic rabies burden and persistent lack of RIG, similar to a majority of rabies endemic countries attempting elimination of the disease.; Data from 3367 patients attending anti-rabies centers (Centres Anti-Rabiques, CARs) of the National Institute for Public Hygiene (Institut National d'Hygiène Publique, INHP) in the departments of Bouaké and San Pédro in Côte d'Ivoire was prospectively collected between April 2016 and March 2018. We identified 1594 patients at risk of rabies infection as eligible for RIG administration. Depending on local availability of eRIG and vaccination protocol applied, PEP consisted of active immunization only (non-eRIG group, n = 1145) or active and passive immunization (eRIG group, n = 449). Patients were followed-up by phone interviews at least 15 months after their exposure to assess for rabies suspected deaths.; Follow-up data was available for 641 patients in the non-eRIG group (56%) and 242 in the eRIG group (54%). Three suspected or possible rabies deaths occurred in each of the two groups, corresponding to a possible rabies mortality of 1.2% (95% CI 0.3-3.6%) in the eRIG group and 0.5% (95% CI 0.1-1.4%) in the non-eRIG group. The difference in proportions was small and not statistically significant (0.7%, p = 0.21). Deaths in both groups were associated with treatment delay after exposure and non-compliance to PEP protocol. No death occurred after correct and timely active immunization independent of eRIG administration.; The provision of eRIG did not lead to a measurable reduction of rabies burden in our study population. This underlines that improved access to active vaccines will be effective in reducing rabies deaths even if access to eRIG remains difficult in developing countries. A possible benefit of eRIG administration for severely exposed patients cannot be excluded based on these results

Modelling to inform prophylaxis regimens to prevent human rabies

International audienceBACKGROUND: The Strategic Advisory Group of Experts (SAGE) Working Group on rabies vaccines and immunoglobulins was established in 2016 to develop practical and feasible recommendations for prevention of human rabies. To support the SAGE agenda we developed models to compare the relative costs and potential benefits of rabies prevention strategies.METHODS: We examined Post-Exposure Prophylaxis (PEP) regimens, protocols for administration of Rabies Immunoglobulin (RIG) and inclusion of rabies Pre-Exposure Prophylaxis (PrEP) within the Expanded Programme on Immunization (EPI). For different PEP regimens, clinic throughputs and consumables for vaccine administration, we evaluated the cost per patient treated, costs to patients and potential to treat more patients given limited vaccine availability.RESULTS: We found that intradermal (ID) vaccination reduces the volume of vaccine used in all settings, is less costly and has potential to mitigate vaccine shortages. Specifically, the abridged 1-week 2-site ID regimen was the most cost-effective PEP regimen, even in settings with low numbers of bite patients presenting to clinics. We found advantages of administering RIG to the wound(s) only, using considerably less product than when the remaining dose is injected intramuscularly distant to the wound(s). We found that PrEP as part of the EPI programme would be substantially more expensive than use of PEP and dog vaccination in prevention of human rabies.CONCLUSIONS: These modeling insights inform WHO recommendations for use of human rabies vaccines and biologicals. Specifically, the 1-week 2-site ID regimen is recommended as it is less costly and treats many more patients when vaccine is in short supply. If available, RIG should be administered at the wound only. PrEP is highly unlikely to be an efficient use of resources and should therefore only be considered in extreme circumstances, where the incidence of rabies exposures is extremely high

Chapitre 16 - Lutte intégrée contre la rage

Introduction La rage est une zoonose type qui touche l’ensemble des mammifères. Elle est généralement transmise de manière envahissante par le biais de la salive qui pénètre une morsure ; elle conduit à une encéphalite avec de graves symptômes distincts qui entraîne le décès. Depuis les toutes premières descriptions de cette maladie ancienne, les animaux, et en particulier les chiens, ont été reconnus comme la source et la cause..

Challenges to improved animal rabies surveillance: experiences from pilot implementation of decentralized diagnostic units in Chad

Better surveillance is desperately needed to guide rabies prevention and control to achieve the goal of zero dog-mediated human rabies by 2030, defined by the World Health Organization (WHO) and partners in 2015. With the help of funding from the Vaccine Alliance (GAVI) learning agenda, we implemented animal rabies surveillance based on One Health communication, improved accessibility of diagnostic testing and facilitated sample transport to increase case detection in three regions of Chad. Through the project, rabies surveillance, previously only available in N'Djamena, was extended to selected provincial rural and urban areas. Nine decentralized diagnostic units (DDU) were established, hosted by veterinary district agencies (VDA) in four different administrative regions. Four additional VDAs in the study area were reinforced with facilitation of sample collection and transport. Staff from all these 13 veterinary facilities were trained in sample collection and diagnostics. DDUs performed Rapid Immunodiagnostic Tests (RIDT) providing a preliminary result before samples were sent to the central laboratory in N'Djamena for confirmation with the standard Florescent Antibody Test (FAT). Within the project period from June 2016 to March 2018, 115 samples were reported by veterinary facilities in the study areas compared to 63 samples received from outside the study area, the vast majority of them originating from the capital city N'Djamena (N=61). Eighty nine percent of all 178 samples reported to IRED during the project period tested positive. Most of the samples originated from dogs (92%). Other confirmed rabies positive animals observed were cats, a donkey and a pig. Although surveillance of animal rabies was the focus, four human saliva samples were also submitted for diagnosis. We observed high differences in reporting rates between the four study regions. This could be attributable to differences in rabies epidemiology but are also influenced by the distance to the central laboratory in N'Djamena, the cultural background and the level of public awareness. The possibility for local testing through RIDT was very welcomed by local veterinary staff and preliminary insights suggest a positive influence on One Health communication and PEP initiation. However, these aspects as well as the relative impact of local testing on sample collection in comparison to reinforcement of sample collection and transport alone, need to be further investigated. Challenges encountered related to poor infrastructure (buildings, appliances, materials) and low logistic capacity (lacking means and material for transport and communication) of veterinary services in Chad. In addition, veterinary personnel lack experience in data management. Together with staff turnover, this leads to a need for repeated training. Major shortcoming of the approach was the high cost per sample and limited sustainability beyond the project timeframe

Increasing rabies data availability: the example of a One Health research project in Chad, Côte d'Ivoire and Mali

Rabies is a fatal but preventable disease that remains notoriously underreported. Weak data availability hampers advocacy, constitutes a barrier to resource allocation and inhibits effective prevention and control. To gain better insight into the global rabies burden and human vaccine demand several studies were funded through the Vaccine Alliance (GAVI) learning agenda. With the help of this funding, Swiss TPH and local in country partner organizations implemented a One Health research project in Chad, Cote d'Ivoire and Mali to collect data at household, public health facility and veterinary level. This paper describes the implementation of this research project and evaluates its success on amount of information gained, achieved capacity building, impact on knowledge creation and influence on national and international policies. The project was based on the One Health concept and guided by the principles of transboundary research partnerships formulated by the Swiss Academy of Sciences. Data was collected on bite incidents and health seeking from over 24'000 households, on access to treatment of over 8'800 bite cases registered in public health facilities and on the status of over 1'800 rabies suspect animals. Selected country specific datasets have contributed to more than 10 scientific articles so far. On the international level, the multi-level data collection provided a unique set of indicators to inform, along with results from other studies, new WHO rabies immunization recommendations and a vaccine investment case scenario to prevent human rabies. New rabies burden estimates based on the data gathered are published for Mali and will be modelled for the whole West and Central African region. On the national level, the project facilitated communication between animal health and human health workers catalyzing creation of local and national committees and formulation of national action plans for Mali and Cote D'Ivoire. Major challenges arose from lack of data collection and documentation experience of human health and veterinary workers and weak infrastructural capacities of the veterinary and human health systems of the project countries. Through adherence to the principles of transboundary research partnerships, project team members acquired valuable research and networking skills despite language barriers, enabling them to play key roles in the future agenda towards national, regional and global canine rabies elimination. Project external collaborations with local public institutions was facilitated through long-term local partnerships. Both factors enabled success in project implementation and outcomes by identifying and mitigating risks in advance, resolving challenges amiably and enabling mutual knowledge creation as a fructuous ground for sustained commitment. Lack of immediate follow-up funding did not allow to maintain activities beyond the project timeframe. However, the national and international policy changes triggered, as well as the strengthened local disease control and research capacities provides sustainable basis for the elimination of dog transmitted human rabies

A metapopulation model of dog rabies transmission in N'Djamena, Chad

Rabies transmission was interrupted for several months in N'Djamena, the capital city of Chad, after two mass vaccination campaigns of dogs. However, there was a resurgence in cases, which was not predicted by previous models of rabies transmission. We developed a deterministic metapopulation model with importation of latent dogs, calibrated to four years of weekly incidence data from passive surveillance, to investigate possible causes for the early resurgence. Our results indicate that importation of latently infective dogs better explains the data than heterogeneity or underreporting. Stochastic implementations of the model suggest that the two vaccination campaigns averted approximately 67 cases of dog rabies (out of an estimated 74 cases without vaccination) and 124 human exposures (out of an estimated 148 human exposures without vaccination) over two years. Dog rabies vaccination is therefore an effective way of preventing rabies in the dog population and to subsequently reduce human exposure. However, vaccination campaigns have to be repeated to maintain the effect or reintroduction through importation has to be prevented