The effectiveness of interventions to reduce cardio-metabolic risk factors among regular street food consumers in Dar es Salaam, Tanzania: The pre-post findings from a cluster randomized trial (Registered by Pan African clinical trial registry with trial # PACTR202208642850935).

INTRODUCTION: The healthy plate model (HPM) is a practical guide to modulate the portion of staple food in main meals, subsequently affecting the risks associated with Non-communicable Diseases include type2 diabetes mellitus (T2DM). OBJECTIVE: This study investigated the effectiveness of health information and the healthy plate model on cardio-metabolic risk factors, knowledge and attitude towards T2DM prevention measures. METHODS: A pre-post analysis, as part of a cluster randomized trial with street food vendors and their customers, was implemented in three randomly selected districts in Dar es Salaam, Tanzania. Two vendor-customer clusters each with 15 and more vendors from each district were randomly assigned to receive either T2DM health information only (Intervention package1 [IP1]) or IP1 plus a subsidized meal with vegetables and fruits, following the principles of the HPM (Intervention package2 [IP2]). Within the clusters the participants were informed on the importance of the intervention they received. An intervention period lasted for three months from 1st April to 31st June 2019. We applied Generalized Linear Mixed Models and Bayesian Modelling (for sensitivity analysis) to assess the effectiveness of the interventions. RESULTS: Overall, 336 (IP2 = 175 and IP1 = 161) out of 560 (280/arm) previous study participants participated in evaluation. Diastolic BP was lower among IP2 participants in the evaluation than baseline AßC = -4.1mmHg (95%CI:-5.42 to -2.76). After adjusting for the interaction between IP2 and age of the consumers, the BMI was significantly lower among IP2 in the evaluation than baseline AßC = -0.7kg/m2 (95%CI: -1.17 to -0.23). With interaction between IP2 and income, BMI was higher in the IP2 in the evaluation than baseline AßC = 0.73kg/m2 (95%CI: 0.08 to 1.38). Systolic and diastolic BP were significantly lower among IP1 in the evaluation than baseline AßC = -3.5mmHg (95%CI:-5.78 to -1.24) and AßC = -5.9mmHg (95%CI:-7.34 to -4.44) respectively. Both the knowledge scores and positive attitudes towards T2DM prevention measures were higher in the evaluation than baseline in both interventions arms. CONCLUSION: The positive effects on cardio-metabolic risk factors, knowledge and attitude were observed in both intervention arms. Due to interactions between IP2, age and income; designing interventions relating to food and cardio-metabolic risk factors, should consider combining socio-economic factors.

Health professionals' knowledge on dengue and health facility preparedness for case detection: A cross-sectional study in Dar es Salaam, Tanzania.

Dengue presents a growing public health concern in the Dar es Salaam region of Tanzania, marked by the recurring incidence of outbreaks. Unfortunately, there is little information available on the region's preparedness in terms of health care workers' knowledge on dengue as well as the availability of reagents and equipment essential for diagnosing and monitoring of dengue infections. To elucidate this, 78 health facilities were visited in Temeke district and structured questionnaires were distributed to 324 health care workers. The aim was to evaluate health care workers' knowledge on dengue and to assess the availability of reagents and equipment essential for diagnosing and monitoring of dengue infections. Content validity of the questionnaire was achieved through extensive literature review and it exhibited high reliability (Cronbach Alpha coefficient = 0.813). Cumulative scores for responses on knowledge questions by health care workers were computed. Characteristics such as level of education, place of work and gender were tested for association with these scores using chi-square tests and logistics regression. Almost all health care workers (99.7%) were aware of dengue disease. However, less than half (46.9%) had knowledge scores of or over 40%. Clinicians had approximately four times higher knowledge scores than other cadres (AOR, 3.637; p-value≤ 0.0001), and those who worked in private facilities had twice the knowledge score than those working in government institutions (AOR, 2.071; p-value = 0.007). Only 8.6%, 35.6% and 14.7% of respondents reported the availability of dengue rapid tests, medical guidelines and refresher training respectively, showing a lack of health facilities readiness for the detection of dengue infections. Based on findings from this study, we recommend government authorities to build capacity of health care workers, to improve their understanding of dengue. We also urge the government and stakeholders to work together to ensure availability of diagnostic tests and other tools needed for diagnosis and surveillance of dengue.

Accelerating the healing of hard-to-heal wounds with food supplements: nutritional analysis in the Côte d'Ivoire.

OBJECTIVE: Hard-to-heal wounds are an important, yet often neglected, public health issue in low- and middle-income countries (LMICs). Malnutrition has been identified as a risk factor for prolonged healing times. However, nutritional supplements are not routinely provided for patients with hard-to-heal wounds, and so this study aimed to investigate their benefits. METHOD: This 9-month study was conducted in the Taabo Health and Demographic Surveillance System in the south-central part of Côte d'Ivoire. Patients with wounds (≥30mm2) were recruited. Treatment was standardised for inpatients (72%) and outpatients (28%). There were three intervention groups: supplemented with soy; orange flesh sweet potato (OFSP); or both. Another group was included without supplement, serving as control. General linear models were employed to assess the effects of log initial wound size, type of wound, food treatment group, haemoglobin, sex, age, place of treatment and body mass index on the rate of wound closure. RESULTS: The cohort consisted of 56 patients, 41 of whom were placed in intervention groups, and the remainder as controls. Within the cohort, 37 (66%) patients suffered from Buruli ulcer, 15 (27%) from traumatic wounds and four (7%) from erysipelas. We found a significant effect (p=0.004) of diet supplemented with OFSP on the wound healing rate. CONCLUSION: OFSP is a nutritional rehabilitation supplement, characterised by a high content of beta-carotene and carbohydrates. It is associated with shortened wound healing times, reduced discomfort and reduced cost of wound care. Further research should investigate the effect of a diet rich in beta-carotene, in combination with standard medical care, on hard-to-heal wound healing in LMICs.

Integrating a community-based continuous mass dog vaccination delivery strategy into the veterinary system of Tanzania: A process evaluation using normalization process theory.

Abstract: Sustained vaccination coverage of domestic dog populations can interrupt rabies transmission. However, challenges remain including low dog owner participation, high operational costs associated with current (centralized and annually delivered (pulse)) approaches and high dog population turnover. To address these challenges an alternative (community-based continuous mass dog vaccination (CBC-MDV)) approach was designed. We investigated the potential for successful normalization of CBC-MDV into routine practice within the context of local communities and the veterinary system of Tanzania. Methods: In a process evaluation of a pilot implementation of CBC-MDV, we conducted in-depth interviews with implementers and community leaders (n = 24), focus group discussion with implementers and community members (n = 12), and non-participant observation (n = 157 h) of delivery of the intervention components. We analyzed these data thematically drawing on the normalization process theory, to assess factors affecting implementation and integration. Main findings: Implementers and community members clearly understood the values and benefits of the CBC-MDV, regarding it as an improvement over the pulse strategy. They had a clear understanding of what was required to enact CBC-MDV and considered their own involvement to be legitimate. The approach fitted well into routine schedules of implementers and the context (infrastructure, skill sets and policy). Implementers and community members positively appraised CBC-MDV in terms of its perceived impact on rabies and recommended its use across the country. Implementers and community members further believed that vaccinating dogs free of charge was critical and made community mobilization easier. However, providing feedback to communities and involving them in evaluating outcomes of vaccination campaigns were reported to have not been done. Local politics was cited as a barrier to collaboration between implementers and community leaders. Conclusion: This work suggests that CBC-MDV has the potential to be integrated and sustained in the context of Tanzania. Involving communities in design, delivery and monitoring of CBC-MDV activities could contribute to improving and sustaining its outcomes.

Digital Technologies to Enhance Infectious Disease Surveillance in Tanzania: A Scoping Review.

Mobile phones and computer-based applications can speed up disease outbreak detection and control. Hence, it is not surprising that stakeholders in the health sector are becoming more interested in funding these technologies in Tanzania, Africa, where outbreaks occur frequently. The objective of this situational review is, therefore, to summarize available literature on the application of mobile phones and computer-based technologies for infectious disease surveillance in Tanzania and to inform on existing gaps. Four databases were searched-Cumulative Index to Nursing and Allied Health Literature (CINAHL), Excerpta Medica Database (Embase), PubMed, and Scopus-yielding a total of 145 publications. In addition, 26 publications were obtained from the Google search engine. Inclusion and exclusion criteria were met by 35 papers: they described mobile phone-based and computer-based systems designed for infectious disease surveillance in Tanzania, were published in English between 2012 and 2022, and had full texts that could be read online. The publications discussed 13 technologies, of which 8 were for community-based surveillance, 2 were for facility-based surveillance, and 3 combined both forms of surveillance. Most of them were designed for reporting purposes and lacked interoperability features. While undoubtedly useful, the stand-alone character limits their impact on public health surveillance.

Risks of snakebite and challenges to seeking and providing treatment for agro-pastoral communities in Tanzania.

BACKGROUND: Continuous occurrence of snakebite incidences and the vulnerability of some communities remain a critical problem in sub-Saharan Africa. Despite causing permanent disability to almost half a million people annually and numerous deaths, snakebite and associated complications are still largely neglected. This study aimed at elucidating risk factors associated with snakebite cases, treatment availability and case management practices for vulnerable agro-pastoralist communities in Northern Tanzania. METHODS: Data was collected in the Monduli (Arusha region) and the Simanjiro (Manyara region) districts in Tanzania. Interviews with 101 snakebite victims or their guardians and 13 health professionals from 3 health centers in the districts were conducted. Additionally, case records of patients admitted between 2007 and 2019 to the Meserani Snakebite Clinic were obtained. RESULTS: This study showed that appropriate treatment for snakebite including anti-venom, is difficult to access and that snakebite incidences were significantly linked to factors such as gender, age, socio-economic activity, season of the year, and whether being at home or out in the fields. Anti-venom and trained health professionals were only available at the Meserani Snake Park Clinic. Men were bitten most often (χ2 = 62.08, df = 4, p-value < 0.0001). Overall, adults between the ages of 18 and 60 years (χ2 = 62.08, df = 4, p-value < 0.0001) received most bites, usually while outdoors herding cattle in the dry season. A significant majority of victims looked for traditional treatment first (52.7%, χ2 = 29.541, df = 2, p-value = 0.0001). The results of this study present crucial information on what is needed to improve the accessibility to appropriate treatment after a snakebite among agro-pastoral communities. CONCLUSION: The situation regarding morbidity and mortality due to the inaccessibility of common treatment for snakebite in northern Tanzania is challenging. Reliance on traditional medicine exacerbates the situation. There is dire need to involve affected communities, researchers, the government, clinicians and the public in general, to work together and take part in the global snakebite initiative. Communities and health professionals recognise the underlying challenges and have valuable suggestions on how to improve the situation.

Barriers to the implementation, uptake and scaling up of the healthy plate model among regular street food consumers: a qualitative inquiry in Dar-es-Salaam city, Tanzania.

INTRODUCTION: The healthy plate model is considered one of the practical approaches to reduce the average portion of staple food in main meals, consequently reducing the risks associated with diabetes and other Non-communicable Diseases (NCDs). Despite its potential benefits, studies on the implementation of the healthy plate model are limited in Africa. An inquiry explored barriers to implementation, uptake, and scaling up of the healthy plate model among street food vendors and consumers in three districts of Dar-es-Salaam city in Tanzania. METHODS: A qualitative research design was adopted. Qualitative data collection techniques were employed including; Key Informant Interviews (KIIs) with purposefully selected food and nutrition stakeholders at the National, Regional, District and Ward levels. Focus Group Discussions (FGDs) were conducted with purposefully selected street food consumers and vendors. A total of (13) KIIs were conducted as well as (6) FGDs with street food vendors (2 FGDs) and consumers (4 FGDs). Interview data was managed using Nvivo 12 Software and analyzed thematically. RESULTS: Three key themes emerged from participants' accounts: (i) strategic policy barriers, (ii) food production and preparation environment barriers (producers and vendors), and (iii) individual barriers (consumers and vendors). The strategic policy barriers included absence of guidelines and regulations that focus on NCDs linked to nutrition and lack of education guidance for vendors and consumers. The food production and preparation environment barriers included safety and risks concerns regarding the quality of water used for irrigation and washing fruits and vegetables and the areas where vegetables and fruits are grown and prepared. Individual barriers included low consumer income, knowledge on nutrition, unhealthy eating practices and; low vendors' knowledge as well as low investment capital. CONCLUSION: Implementation, uptake and scaling up of the healthy plate model for street food consumers in Dar es Salaam City continues to be constrained by barriers in policy, food production and preparation environment, and individual obstacles. Strengthening of food and nutrition policies, ensuring safety of the food production and preparation environment and, consumer and vendor awareness creation and income generation efforts, provide useful entry points for the successful scaling up of a healthy plate model. This could consequently contribute towards prevention of diet related NCDs, including diabetes.

Participation in mass dog vaccination campaigns in Tanzania: Benefits of community engagement.

Background: Canine rabies causes about 59,000 human deaths each year globally but the disease can be eliminated by sustaining sufficient dog vaccination coverage over several consecutive years. A challenge to achieving high coverage is low participation of dog owners in vaccination campaigns. We explored whether and how previously identified contributory factors to low participation can be addressed through community engagement activities. Methods: We engaged communities in two wards in Tanzania on dog behavior and handling, safe ways of interacting with dogs, and their perceptions of dog vaccination. We shared and elicited information from them through village meetings, video screenings, posters and leaflets and involved the leadership of one of the wards in planning and implementing a dog vaccination exercise to explore the feasibility of their participation. We assessed the impact of engagement activities with household surveys, meeting reports, observations and focus group discussions. We used a generalized linear mixed-effects model to identify predictors of knowledge and perceptions and compared knowledge amongst respondents before and after engagement activities. Qualitative data was analyzed inductively to explore perceptions of dog handling and vaccination and feasibility, opportunities and barriers to community leadership participation in organizing mass dog vaccination. Main findings: Knowledge of dog behavior, dog handling, and safe ways of interacting with dogs was positively associated with age (p < 0.0001), dog ownership (p = 0.0203), training (p = 0.0010) and previous experience of a dog bite (p = 0.0002); and was negatively associated with being afraid of dogs (p = 0.0061) and participation in a recent dog vaccination campaign (p = 0.0077). Knowledge was low before and significantly improved after engagement activities. The majority (92%) of respondents believed dog vaccination has no negative effects on dogs. Respondents perceived lack of bonding with their dog as a limitation to the ability to restrain a dog for vaccination. The community performed most roles assigned to them in the dog vaccination exercise, but barriers such as lack of motivation for volunteering exist. Conclusion: Engaging communities regularly on dog vaccination can improve their knowledge of dog behavior and dog handling techniques, and may help improve owner participation in dog vaccination campaigns.

Development, feasibility and potential effectiveness of community-based continuous mass dog vaccination delivery strategies: Lessons for optimization and replication.

OBJECTIVES: Dog vaccination can eliminate rabies in dogs, but annual delivery strategies do not sustain vaccination coverage between campaigns. We describe the development of a community-based continuous mass dog vaccination (CBC-MDV) approach designed to improve and maintain vaccination coverage in Tanzania and examine the feasibility of delivering this approach as well as lessons for its optimization. METHODS: We developed three delivery strategies of CBC-MDV and tested them against the current annual vaccination strategy following the UK Medical Research Council's guidance: i) developing an evidence-based theoretical framework of intervention pathways and ii) piloting to test feasibility and inform optimization. For our process evaluation of CBC-MDV we collected data using non-participant observations, meeting reports and implementation audits and in-depth interviews, as well as household surveys of vaccination coverage to assess potential effectiveness. We analyzed qualitative data thematically and quantitative data descriptively. RESULTS: The final design included delivery by veterinary teams supported by village-level one health champions. In terms of feasibility, we found that less than half of CBC-MDV's components were implemented as planned. Fidelity of delivery was influenced by the strategy design, implementer availability and appreciation of value intervention components, and local environmental and socioeconomic events (e.g. elections, funerals, school cycles). CBC-MDV activities decreased sharply after initial campaigns, partly due to lack of supervision. Community engagement and involvement was not strong. Nonetheless, the CBC-MDV approaches achieved vaccination coverage above the critical threshold (40%) all-year-round. CBC-MDV components such as identifying vaccinated dogs, which village members work as one health champions and how provision of continuous vaccination is implemented need further optimization prior to scale up. INTERPRETATION: CBC-MDV is feasible to deliver and can achieve good vaccination coverage. Community involvement in the development of CBC-MDV, to better tailor components to contextual situations, and improved supervision of activities are likely to improve vaccination coverage in future.

Plasmid characterization in bacterial isolates of public health relevance in a tertiary healthcare facility in Kilimanjaro region, Tanzania.

OBJECTIVES: Plasmids are infectious double stranded DNA molecules that are found within bacteria. Horizontal gene transfer promotes successful spread of different types of plasmids within or among bacteria species, making their detection an important task for guiding clinical treatment. We used whole genome sequenced data to determine the prevalence of plasmid replicon types in clinical bacterial isolates, the presence of resistance and virulence genes in plasmid replicon types, and the relationship between resistance and virulence genes within each plasmid replicon. METHODS: All bacterial sequences were de novo assembled using Unicycler before extraction of plasmids. Assembly graphs were submitted to Gplas+plasflow for plasmid contigs prediction. The predicted plasmid contigs were validated using PlasmidFinder. RESULTS: A total of 159 (56.2%) out of 283 bacterial isolates were found to carry plasmid replicons, with Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus being the most prevalent plasmid carriers. A total of 26 (86.7%) multiple-replicon types were found to carry both resistance and virulence genes compared to 4 (13.3%) single plasmid replicons. No statistically significant correlation was found between the number of antibiotic resistance and virulence genes in multiple-replicon types (r = - 0.14, P > 0.05). CONCLUSION: Our findings show a relatively high proportion of plasmid replicon-carrying isolates suggesting selection pressure due to antibiotic use in the hospital. Co-occurrence of antibiotic resistance and virulence genes in clinical isolates is a public health problem warranting attention.

Determinants of Rabies Post-exposure Prophylaxis Drop-Out in the Region of San-Pedro, Côte d'Ivoire.

Abstract: Despite the fact that death from rabies is 100% preventable with a course of post-exposure prophylaxis (PEP) treatment, canine rabies still causes about 59,000 human deaths worldwide annually, half of which are occurring in Africa. In Côte d'Ivoire, rabies remains a threat partly due to the high drop-out rate of the life-saving human PEP treatment among people exposed to dog bites. Each year, half of the victims starting treatment, do not complete the course. The current study therefore assessed the determinants for drop-out of the life-saving treatment among people exposed to rabies in the department of San-Pedro in Côte d'Ivoire. Methods: A mixed-methods approach was used, including questionnaires, observation, individual interviews and focus group discussions, to gather socio-demographic and economic data from 235 participants about possible reasons for abandoning treatment. The study population consisted of patients and medical and veterinary health professionals who were selected using stratified sampling and purposive selection from a database available at the Rabies Center of San Pedro. Result: The drop-out of PEP treatment was related to perception bias and a habit of low attendance of health care and vaccination centers in the population. Quantitative analysis shows differences between rural and urban areas and an association with age when it comes to treatment completion. The dropout rate was most significant among patients who, in case of other illness, did not routinely see a doctor or go to vaccination centers. The rate of abandonment was higher among those who believed that dog-related injuries could be easily treated at home, and who believed that a person with rabies could be cured without completing the preventive treatment. Insufficient provision of health information on rabies and logistic constraints related to the practical organization of treatment, including the long distance to the anti-rabies center and weaknesses in the patient follow-up procedure, did not contribute to the completion of PEP. Conclusion: Established determinants for drop-out provide a framework for effective design and implementation of rabies control strategies to accelerate rabies deaths elimination efforts. In particular, access to PEP and community knowledge about rabies need to be improved and integrated in the health system and education system, respectively.

Evaluation of the Pfs25-IMX313/Matrix-M malaria transmission-blocking candidate vaccine in endemic settings.

Malaria control relies heavily on the use of anti-malarial drugs and insecticides against malaria parasites and mosquito vectors. Drug and insecticide resistance threatens the effectiveness of conventional malarial interventions; alternative control approaches are, therefore, needed. The development of malaria transmission-blocking vaccines that target the sexual stages in humans or mosquito vectors is among new approaches being pursued. Here, the immunological mechanisms underlying malaria transmission blocking, status of Pfs25-based vaccines are viewed, as well as approaches and capacity for first in-human evaluation of a transmission-blocking candidate vaccine Pfs25-IMX313/Matrix-M administered to semi-immune healthy individuals in endemic settings. It is concluded that institutions in low and middle income settings should be supported to conduct first-in human vaccine trials in order to stimulate innovative research and reduce the overdependence on developed countries for research and local interventions against many diseases of public health importance.

Modeling nosocomial infection of COVID-19 transmission dynamics.

COVID-19 epidemic has posed an unprecedented threat to global public health. The disease has alarmed the healthcare system with the harm of nosocomial infection. Nosocomial spread of COVID-19 has been discovered and reported globally in different healthcare facilities. Asymptomatic patients and super-spreaders are sough to be among of the source of these infections. Thus, this study contributes to the subject by formulating a S E I H R mathematical model to gain the insight into nosocomial infection for COVID-19 transmission dynamics. The role of personal protective equipment θ is studied in the proposed model. Benefiting the next generation matrix method, R 0 was computed. Routh-Hurwitz criterion and stable Metzler matrix theory revealed that COVID-19-free equilibrium point is locally and globally asymptotically stable whenever R 0 < 1 . Lyapunov function depicted that the endemic equilibrium point is globally asymptotically stable when R 0 > 1 . Further, the dynamics behavior of R 0 was explored when varying θ . In the absence of θ , the value of R 0 was 8.4584 which implies the expansion of the disease. When θ is introduced in the model, R 0 was 0.4229, indicating the decrease of the disease in the community. Numerical solutions were simulated by using Runge-Kutta fourth-order method. Global sensitivity analysis is performed to present the most significant parameter. The numerical results illustrated mathematically that personal protective equipment can minimizes nosocomial infections of COVID-19.

Effectiveness and cost of an incentive-based intervention on food safety and income in "dibiteries" in Dakar, Senegal.

BACKGROUND: Rapid urbanisation in Sub-Saharan African cities such as Dakar, Senegal, leads to proliferation of informal braised meat restaurants known as "dibiteries". Dibiteries do not often comply with minimal hygiene and food safety standards. The primary objective of this study was to assess the effectiveness and cost of a good hygiene practice intervention, identify factors that incentivize hygiene improvement and how that impacts on dibiteries' income. METHODS: A randomized controlled trial was carried out in Dakar dibiteries. The 120 random samples of braised meat were collected in three phases: (i) one-month pre-intervention, (ii) 2 months post-intervention, (iii) 10 months post-intervention. The trial comprised four groups of 10 dibiteries each: (a) (control) received no intervention, (b) a standardized training module, (c) a hygiene kit, (d) a training module and hygiene kit. Laboratory analysis of samples determined the total aerobic mesophilic flora (TAMF), thermotolerant coliforms (TC) and Staphylococcus aureus (SA). A questionnaire-based survey and focus group discussion were used to identify pre-intervention hygiene practices, and socioeconomic determinants of hygiene management in dibiteries post-intervention, respectively. RESULTS: Samples were found to be contaminated with TAMF, TC and SA. In phase 1, 27 and 13% of the samples contained TC and SA, respectively. In phase 2, no significant improvement of contamination rates was seen. In phase 3, microbiological quality of samples was significantly improved, with only 11.5% showing contamination with any of the bacterial species analysed (p < 0.1). Compared to the control group, only samples from dibiteries in group (b) had significantly reduced bacterial load in phase 3. The cost of intervention and hygiene improvement was estimated at 67 FCFA ($ 0.12) and 41 FCFA ($ 0.07) / day respectively and did not significantly impact on dibiterie profitability. Incentives to sustainably implement good hygiene practices were mainly linked to access to secure long-term workspaces. CONCLUSION: This intervention may have worked, but globally the results are mixed and not quite significant. However, continuous training in good hygiene practice and access to secure and sustainable infrastructure for dibiterie restaurants are the incentives necessary to achieve sustainable investments and behavioural change. We recommend further intervention refinement and testing other factors for promoting the adoption of good hygiene practices in the dibiteries in relation to consumers health risk.

Use of lay vaccinators in animal vaccination programmes: A scoping review.

BACKGROUND: The human resource gap in veterinary sectors, particularly in low-income countries, imposes limitations on the delivery of animal healthcare in hard-to-reach populations. Lay animal health workers have been deployed in these settings to fill the gap though there are mixed views about the benefits of doing this and whether they can deliver services safely. We mapped evidence on the nature and extent of roles assigned to lay animal vaccinators, and identified lessons useful for their future deployment. METHODOLOGY/PRINCIPAL FINDINGS: Following the PRISMA Extension for Scoping Reviews guidelines, we searched seven bibliographic databases for articles published between 1980 and 2021, with the search terms lay OR community-based OR volunteer AND "animal health worker" OR vaccinator*, and applied an a priori exclusion criteria to select studies. From 30 identified studies, lay vaccinators were used by non-government developmental (n = 12, 40%), research (n = 10, 33%) and government (n = 5, 17%) programmes to vaccinate domestic animals. The main reason for using lay vaccinators was to provide access to animal vaccination in the absence of professional veterinarians (n = 12, 40%). Reported positive outcomes of programmes included increased flock and herd sizes and farmer knowledge of best practice (n = 13, 43%); decreased disease transmission, outbreaks and mortality (n = 11, 37%); higher vaccination coverage (10, 33%); non-inferior seroconversion and birth rates among vaccinated herds (n = 3, 10%). The most frequently reported facilitating factor of lay vaccinator programmes was community participation (n = 14, 47%), whilst opposition from professional veterinarians (n = 8, 27%), stakeholders seeking financial gains to detriment of programmes goals (n = 8, 27%) and programming issues (n = 8, 27%) were the most frequently reported barriers. No study reported on cost-effectiveness and we found no record from a low and middle-income country of lay vaccinator programmes being integrated into national veterinary services. CONCLUSION: Although the majority of included studies reported more benefits and positive perceptions of lay vaccinator programmes than problems and challenges, regularization will ensure the programmes can be designed and implemented to meet the needs of all stakeholders.

Design and validation of a food frequency questionnaire to assess the dietary intake for adults in pastoral settings in Northern Tanzania.

OBJECTIVE: Food frequency questionnaires are widely used as a dietary assessment tool in nutritional epidemiology to determine the relationship between diet and diseases. In Tanzania, there are several cultural variations in food intake which makes it necessary to design and validate a culture-specific food frequency questionnaire (CFFQ). Therefore, we designed a 27-items CFFQ and examine its validity in pastoral communities. Validity of CFFQ was assessed by comparing nutrient intake estimated from the CFFQ against the average from two 24-h diet recall (2R24). Spearman's correlation coefficients, cross classification and Bland-Altman's methods were used to assess the validity of CFFQ. RESULTS: A total of 130 adults aged 18 years and above completed both CFFQ and 2R24. Correlation coefficients between CFFQ and 2R24 ranged from low (r = - 0.07) to moderate (r = 0.37). The correlation coefficients were moderately significant for kilocalories (r = 0.31, p < 0.001), carbohydrate (r = 0.33, p < 0.001), magnesium (r = 0.37, p < 0.001), and iron (r = 0.34, p < 0.001). On average, about 69% of participants were correctly classified into the same or adjacent quartile of energy and nutrient intake, while 9% were misclassified by the CFFQ. Bland-Altman's plot demonstrated that the CFFQ had acceptable agreement with the 2R24.

Lay attitudes and misconceptions and their implications for the control of brucellosis in an agro-pastoral community in Kilombero district, Tanzania.

Brucellosis is a priority zoonotic disease in Tanzania that causes ill-health in people and affects livestock productivity. Inadequate awareness and behavior risking transmission can impede control efforts. We conducted a cross-sectional survey of 333 livestock owners in three villages in the Kilombero district, Tanzania, to understand their awareness, knowledge and behavior associated with brucellosis. Six Focus Group Discussions (FGDs), two in each village, were conducted, as well as an additional FGD with male herders from one of the villages. Factors associated with knowledge on brucellosis, food consumption and animal husbandry behavior risking transmission of this disease, were identified using generalized linear models. Predictors for knowledge of brucellosis were being male and having a higher educational level, while age was positively associated with a higher level of knowledge. Faith and ethnicity were associated with the performance of practices risking transmission. Following traditional religion and belonging to the Wamaasai ethnicity significantly increased the odds of carrying out these practices. Qualitative analysis gave insight into risk practices and reasoning. Of the 333 respondents, 29% reported that they had experienced abortions in their herds, 14% witnessed retained placentas, and 8% had seen still-births in their cattle within the previous year. However, survey results also showed that only 7.2% of participants had heard about brucellosis as a disease in livestock. Of those who had heard about brucellosis in livestock, 91% associated abortions with it and 71% knew that humans can get infected through raw milk consumption. People overwhelmingly attributed symptoms and transmission of brucellosis in livestock to infection with trypanosomiasis and to supernatural reasons instead. In the community, consumption of raw milk was valued and handling of aborted material was not considered a risk for infection. This agro-pastoralist community holds on to long-held beliefs and practices and lacks understanding of the biomedical concept of brucellosis. Transmission routes and symptoms of brucellosis in humans and livestock are completely unknown. The disparity between risk perception and actual transmission risk related to animal handling and consumption of animal products presents a challenge for disease awareness communication. This study recommends focused community engagement and sensitization to address the limited awareness and misconceptions among agro-pastoralists.

Semi-field evaluation of the exposure-free mosquito electrocuting trap and BG-Sentinel trap as an alternative to the human landing catch for measuring the efficacy of transfluthrin emanators against Aedes aegypti.

BACKGROUND: The human landing catch (HLC) measures human exposure to mosquito bites and evaluates the efficacy of vector control tools. However, it may expose volunteers to potentially infected mosquitoes. The mosquito electrocuting trap (MET) and BG-Sentinel traps (BGS) represent alternative, exposure-free methods for sampling host-seeking mosquitoes. This study investigates whether these methods can be effectively used as alternatives to HLC for measuring the efficacy of transfluthrin emanator against Aedes aegypti. METHODS: The protective efficacy (PE) of freestanding passive transfluthrin emanators (FTPEs), measured by HLC, MET and BGS, was compared in no-choice and choice tests. The collection methods were conducted 2 m from an experimental hut with FTPEs positioned at 3 m on either side of them. For the choice experiment, a competitor HLC was included 10 m from the first collection point. One hundred laboratory-reared Ae. aegypti mosquitoes were released and collected for 3 consecutive h. RESULTS: In the no-choice test, each method measured similar PE: HLC: 66% (95% confidence interval [CI]: 50-82), MET: 55% (95% CI: 48-63) and BGS: 64% (95% CI: 54-73). The proportion of mosquitoes recaptured was consistent between methods (20-24%) in treatment and varied (47-71%) in the control. However, in choice tests, the PE measured by each method varied: HLC: 37% (95% CI: 25-50%), MET: 76% (95% CI: 61-92) and BGS trap: 0% (95% CI: 0-100). Recaptured mosquitoes were no longer consistent between methods in treatment (2-26%) and remained variable in the control (7-42%). FTPE provided 50% PE to the second HLC 10 m away. In the control, the MET and the BGS were less efficacious in collecting mosquitoes in the presence of a second HLC. CONCLUSIONS: Measuring the PE in isolation was fairly consistent for HLC, MET and BGS. Because HLC is not advisable, it is reasonable to use either MET or BGS as a proxy for HLC for testing volatile pyrethroid (VP) in areas of active arbovirus-endemic areas. The presence of a human host in close proximity invalidated the PE estimates from BGS and METs. Findings also indicated that transfluthrin can protect multiple people in the peridomestic area and that at short range mosquitoes select humans over the BGS.