Magnetic resonance imaging in rabies encephalitis, a case report, and review of the literature

Rabies is an acute fatal disease of the central nervous system. Neuroimaging plays an important role, especially in establishing an early diagnosis and distinguishing it from other types of encephalitis. This case report aims to give a brief review of this condition and report the less common MRI findings of the disease. We herein report a case of a 61-year-old male bitten by a stray dog who presented with fever, vomiting, headache, sialorrhea, dysarthria, dysphagia, and upper limb weakness which progressed to lower limbs on the next day. T2W and FLAIR images demonstrated subtle bilateral hyperintense signal in the deep gray matter with more apparent increased signal intensity in the white matter of the frontal and parietal lobes which shows mild diffusion restriction but no postcontrast enhancement. The diagnosis of rabies encephalitis was made based on a typical history of exposure, a compatible clinical presentation, and MRI findings. Rabies diagnosis is essentially clinical. It is definitively confirmed by the isolation of the virus from biological samples such as saliva, CSF, hair, or detection of rabies antigens or antibodies. Magnetic resonance imaging (MRI) brain used as one of the modalities of investigation for distinguishing it from other encephalitis. Rabies per se does not have any characteristic features on the MRI brain.

General insights on obstacles to dog vaccination in Chad on community and institutional level

Domestic dogs are responsible for 95% of all human rabies cases worldwide and continue to be the main reservoir for this fatal virus in African and Asian countries. Interrupting the spread of the disease in the domestic dog population is therefore necessary for long-term, sustainable rabies control. Chad has been recognized as a rabies-endemic country since 1961, but no national control strategy is in place to date and dog vaccination coverage is very low. This qualitative, descriptive study aims to describe the main barriers to dog vaccination on both the community and the institutional level from a socio-anthropological point of view in Chad. The study was embedded in an overall project conducted from 2016 to 2018, to determine rabies burden and vaccine demand in West and Central Africa, funded by GAVI, the vaccine alliance. Data collection was conducted on the occasion of the project's closing workshops with stakeholders organized between August to September 2018 in the four (4) project areas: Logone Occidental, Ouaddaï, Hadjer Lamis and Chari Baguirmi. We conducted interviews and focus group discussions (FGD) among veterinary officers and dog owners. Participants were selected purposively based on their place of residence (dog owners) or work place (veterinary officers) and their previous contact with the project through reporting (dog owner) or management (veterinary officers) of a suspect dog rabies case. In each region, one FGD was organized with dog owners, and one FGD with heads of veterinary posts. At the end of the FGDs, a few participants were randomly selected for interviews. In addition, in each region an interview was conducted with the head of the livestock sector, the chief district medical officers and the head of a civil society association. The identified barriers to dog vaccination access are grouped into three main aspects: the economic, the socio-cultural and the institutional level. Economic constraints encountered relate to the cost of the vaccine itself and the expenses for transporting the dogs to the vaccination site. The cultural belief that the vaccine will have an impact on the therapeutic properties of dog meat for consumers (observed in Southern Chad), and the fact that dogs are considered impure animals in Muslim faith, which prohibits handling of dogs, are obstacles identified on the sociocultural level. At the institutional level, the unavailability of vaccines in veterinary services, the lack of communication about the law on dog vaccination, the absence of rabies in the training curricula of veterinary agents, and the lack of intersectoral collaboration limit vaccination coverage. In order to improve vaccination coverage and rabies surveillance with a view to eradicate rabies by 2030, communication strategies that are adapted to the context and that take cultural obstacles into account must be put in place in a synergy of interdisciplinary action. In addition, factors such as affordability, geographical access and availability of dog rabies vaccines needs to be addressed throughout the country. Although our study design did not allow a detailed analysis of obstacles related to socio-economic level, gender and age the broad insights gained can provide general guidance for future interventions in Chad and similar countries.

"When a dog bites someone": Community and service provider dynamics influencing access to integrated bite case management in Chad

This study aims to identify factors on the community, the human health and the animal health provider level that determine access to Post Exposure Prophylaxis (PEP) and animal rabies diagnosis in the light of a future integrated bite case management (IBCM) approach for rabies control in Chad. The study was embedded in an overall project conducted from 2016 to 2018, to determine rabies burden and vaccine demand in West and Central Africa. Data collection took place during the projects closing workshops with stakeholders organized between August and September 2018 in the three study zones in Chad covering Logone Occidental and Ouaddaï province and parts of Hadjer Lamis and Chari Baguirmi province. A qualitative approach based on focus group discussion and in-depth interviews was used to get insights on access to care and animal investigation after suspected rabies exposure. A total of 96 participants, including 39 from the community (bite victims, dog owners) and 57 human and animal health providers (health center managers, chief veterinary officers, chief district medical officers, chiefs of livestock sectors) contributed to the study. Based on an existing conceptual framework of access to health care, several points of dissatisfaction were identified, in particular the unaffordability of human rabies vaccine for PEP (affordability) and the distance to travel to a health facility in case of a bite (accessibility). In addition, there are unfavorable attitudes observed highlighted by the importance given to traditional or local rabies care practices to the detriment of PEP (acceptability) and a low level of knowledge among Chadian communities regarding bite prevention, coupled with a very inadequate information and awareness system regarding the disease (adequacy). As for human and veterinary health services, both sectors suffer from insufficient resources for PEP on the human health and rabies diagnosis on the veterinary side impacting negatively on availability and accessibility of both these services. Action to improving provision of rabies health services and increasing knowledge about risk and prevention of the disease among the population need to be undertaken to implement IBCM, improve access to PEP and achieve the goal of eliminating dog mediated human rabies by 2030 in Chad.

Knowledge, Attitudes and Practices on Rabies among Human and Animal Health Professionals in Senegal

Rabies is still a public health problem in Senegal. This study aimed to assess the knowledge, attitudes and practices on rabies among human and animal health professionals. It was a cross-sectional, descriptive and analytical study conducted in the Kaffrine district. Data were collected from 28 June to 01 July 2021. An exhaustive recruitment was done, and the final sample size was 95 health professionals. R software was used for descriptive, bivariate and multivariate analyses. Health professionals with sufficient knowledge, positive attitudes and good practices in relation to rabies represented 35.8%, 26.3% and 45.3% of the study respectively. The results of the multivariate analysis showed that professionals who worked in urban areas (AOR = 11.10; 95% CI = [3.50-41.69]) and who worked in animal health (AOR = 7.45; 95% CI = [1.16-70.40]) were more likely to have sufficient knowledge about rabies. Professionals with tertiary education (AOR = 12.40; CI95% = [1.80-268.00]) and with sufficient knowledge (AOR = 3.41; CI95% = [1.01-12.70]) were more likely to have a positive attitude about rabies. Professionals with a positive attitude about rabies (AOR = 3.23; 95% CI = [1.08-10.70]) were more likely to have a good practice when presented with an animal bite case. These results suggest that improving health professionals' knowledge about rabies is essential in order to influence their attitudes and practices against rabies.

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'Djaména, 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'Djaména (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'Djaména, 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.

Identification of risk factors for rabies exposure and access to post-exposure prophylaxis in Chad

Rabies remains a global public health problem, with Africa as one of the most affected continents. Endemic transmission in the unvaccinated domestic dog population of developing countries leads to many exposures with subsequent death in humans due to lack of access to existing effective prevention tools. The presented study identifies factors of exposure and rabies risk in Chad on the household and health facility levels and highlights the challenges of access to Post Exposure Prophylaxis (PEP). Data on bite exposure and prevention was collected through a representative cross-sectional survey in rural and urban households and through a continuous bite reporting survey in public health facilities. During the household survey 8000 homes were visited, including 3241 (41%) in urban areas and 4759 (59%) in rural areas. The frequency of dog ownership was similar in both rural and urban areas, with around 24% households owning at least one dog. Knowledge of rabies as a disease transmitted mainly from dogs to humans was generally good, but higher in urban (86%) compared to rural areas (73%). The need for early prevention and medical care after a bite was less well known with 35% of respondents believing that rabies is curable after onset of symptoms and only one in three bite victims seeking help in a health facility. Exposure risk based on bite incidence on the population level was increased for Christian compared to Muslim predominant religious context. During the health facility study, 1540 bite cases were registered, of which 58% originated from urban areas and 42% from rural areas. Demographic characteristics of the health facility data subset matched the household survey data subset for the majority of parameters. Only bites from known animals (same household or from neighbourhood) and bites from animals known to be alive were underrepresented, suggesting that such bites are regarded as less dangerous than bites from unknown animals and animals that died, were killed or disappeared. Since human vaccine was provided free of charge during the study, most victims received PEP (84%). However, not all patients completed treatment, with a higher risk of non-compliance observed in rural areas. Access to vaccine before the study was alarmingly low, with only 8.5% accessing PEP. Despite facilitated collaboration between human health and veterinary services through the project, consultation with veterinary services remained generally low. The observed challenges can inform future rabies control programmes on the national level to effectively increase access to PEP exceeding the expected improved availability of human vaccine through the upcoming GAVI investment.

Rabies knowledge and practices among human and veterinary health workers in Chad

To prevent human rabies deaths close communication between the veterinary and human health sector is needed for timely and adequate treatment after a bite exposure. Good practice treatment and efficient One Health communication depends heavily on the knowledge and practices (KP) of both human health and veterinary workers. We have evaluated the level of KP of both these sectors during a one-day joint training program to kick start a large scale rabies burden and vaccine demand study in selected regions of Chad. Participants were evaluated through a questionnaire before and after training to get insight into the basic knowledge of rabies and the improvement of this knowledge after the training session. In addition to 20 questions on rabies derived from the educational platform of the Global Alliance for Rabies Control, the questionnaires included a pre-training knowledge self-evaluation and a post-training evaluation of the course. Overall 247 workshop participants with varied level of educational background responded to at least one questionnaire. Around 75% of respondents were from the human health sector and 20% from the veterinary sector. Knowledge level did not differ significantly between the two sectors nor between rural or urban working backgrounds. Respondents with a university degree scored significantly higher in pre-and post-training questionnaire compared to respondents with high school level degree or lower. Knowledge was also dependent on study region and sex of the respondent. In general, the importance of a One Health approaches, such as vaccination of dogs to prevent human rabies, is well understood in both sectors. Regarding treatment, many participants did not know the adequate number of doses required for a full course of PEP, but through the training, this knowledge improved. Detailed knowledge of atypical transmission routes and pathophysiology (neurotropism of the virus) was generally lacking and did not significantly improve through the training. The study revealed considerable deficiencies and challenges in the knowledge level of both veterinary and human health workers in Chad. Rabies control programs need to anticipate these challenges to implementation and provide sufficient time and funds for training workshops and follow-up.