Sharadhuli Iddi Kimera

Introduction: Mass dog vaccination prevents human rabies deaths by interrupting transmission in source populations. However, resources, including trained personnel, cold chain and infrastructure constrain vaccination delivery strategies and impact their effectiveness. We investigate the interaction between delivery strategies and performance of dog vaccination programmes. Methods: Leveraging a three-year cluster-randomised controlled trial in Mara region, Tanzania (population 2.3 million, 112 wards), we compared a centralised annual team-led strategy with a decentralised community-led hybrid enabling year-round delivery, made possible by vaccine thermotolerance. We used regression analysis to undertake controlled comparisons of effectiveness and cost-effectiveness. Findings: The community-led strategy achieved superior coverage, increasing by 10% per 1,000 dog vaccinations per ward (p<0.001). It sustained coverage above the 40% herd immunity threshold for 7–8 months annually, a 33% increase in temporal protection versus annual team-led delivery, which experienced 39% coverage declines without re-vaccination. The community-led approach cost approximately $800 per ward to reach the threshold, compared to $2,100 for team-led delivery. Interpretation: Dog vaccination delivery timing and structure strongly influence programme performance. Community-led strategies offer a cost-efficient pathway to sustaining herd immunity in resource-limited settings, addressing the challenge of attaining and maintaining sufficient vaccination coverage to interrupt transmission and reduce exposure risks.

Scabies, caused by Sarcoptes scabiei, is a neglected tropical disease that disproportionately affects underserved rural communities, where transmission is commonly sustained through prolonged close contact and sharing of personal items.This study assessed household scabies experience and associated factors during a past outbreak in Nyasa District. A retrospective community based cross sectional study was conducted among 198 households from four villages. Data were collected using an AfyaData digitized, expert validated questionnaire aligned with the International Alliance for the Control of Scabies criteria to improve syndromic specificity. Quantitative data were analyzed using univariable and multivariable logistic regression. Open ended responses were analyzed thematically and triangulated with regression findings. Overall, 60.6% of households reported scabies experience during the outbreak period. In multivariable analysis, higher odds of household scabies experience were associated with sharing personal items (Rarely AOR = 4.059; Frequent AOR = 4.688) and receiving treatment during the outbreak (AOR = 4.705). Non collaboration with healthcare personnel showed increased odds but was not statistically significant (AOR = 2.035; p = 0.098). Households reporting unsure answers for previous scabies history (AOR = 0.235) and treatment (AOR = 0.249) had lower odds, indicating misclassification due to uncertainty. The following determinants were linked to qualitative themes: sharing items related to laundry, bedding, and clothing hygiene practices; treatment related to concerns about effectiveness and barriers to access; collaboration related to requests for education, outreach, and follow up; and unsure responses related to misunderstandings and uncertainty. In addition to highlighting the need for coordinated outbreak responses that prioritize household level prevention, reducing the sharing of personal items, improving access to effective treatment, and strengthening health system community engagement, the study shows a significant household burden of scabies. Triangulation of regression results with community narratives supports AfyaData value for standardized, criteria-informed investigation and targeted public health action in Tanzania.

Tuberculosis (TB) in cattle negatively affects the cattle economy in Africa, with zoonotic TB posing drug-resistance issues in humans. The burden of TB in cattle and zoonotic TB in humans in sub-Saharan Africa (SSA) is not well understood. This study aimed to determine the prevalence of both TB in cattle and zoonotic TB in humans in SSA through meta-analysis. Research on TB prevalence was sourced from multiple databases. A random effects meta-analysis model estimated TB prevalence in SSA and its regions, while meta-regression identified risk factors. The analysis included 114 studies for cattle and 59 for humans. The estimated TB prevalence in cattle was 5.06% (95% CI: 3.76-6.78), with a higher burden in West Africa. The prevalence was greater on farms than at abattoirs. Among humans, M. bovis prevalence was 0.73% (95% CI: 0.53-1.01), increasing to 1.56% (95% CI: 1.04-2.33) in TB incident cases, especially in the West and East Africa. Higher prevalence was noted among livestock workers, and in drug-resistant cases. Significant factors influencing TB prevalence varied for cattle and humans, including country, diagnostic methods, and study populations. Focusing interventions on farms and livestock workers could help reduce the disease burden.

Background: Rodents are known to be a source of foodborne diseases; however, few researchers have examined rodent faeces. Purpose: This study aimed to determine the prevalence of foodborne Salmonella spp. and Escherichia coli (E. coli) and the risk factors associated with rodents and shrews in five wards from Morogoro Municipality, Tanzania. Method: A total of 148 rodents and shrews were captured from domestic, peri-domestic, and marketplace settings. This study isolated bacteria from faeces samples collected from rodents and shrews using a culture test, and identified them using biochemical tests. Molecular tests were used to screen out bacteria-targeted genes. Questionnaires were also used to assess the risk factors of foodborne Salmonella spp. and E. coli associated with house rodents and shrews. Results: Salmonella enterica was detected in 3/148 (2%), and E. coli was found in 54/148 (36.5%) of the samples. Regarding habitat, a high prevalence of E. coli was observed in open markets, at 16.9%, while Salmonella enterica was high inside households, at 1.3%. The results show that 83% of respondents found rodents feces in uncooked or cooked food, 30.4% found rodents feces in the water storage, 93.2% found food eaten by a rodent, and 66.9% of households used food contaminated with feces or eaten by rats. Conclusion: The study shows that rodents and shrews carry foodborne pathogens like Salmonella enterica and Escherichia coli in Morogoro municipality, Tanzania, posing serious public health risks. The rodents had high rates of E. coli and low Salmonella enterica, with risk factors linked to food and water contamination.

This study aimed to assess Maasai pastoralists’ perception and attitude towards the spread and impacts of sickle bush (Dichrostachys cinerea) in their grazing lands. The study was conducted in three villages of Monduli district involving 156 randomly sampled households. Thirteen (13) purposively selected key informants (based on their merits) were interviewed and participant observation was also used in data collection. Quantitative data were analyzed by the SPSS software version 20, while qualitative ones were subjected to content analysis. Findings revealed that the current extent of the sickle bush has increased, with over 70% of the respondents proving this. About 82% of respondents revealed that the bush was present in their villages for a long time, although its invading effects have increased. Major reasons for this invasion were reported to include climate change and overgrazing. Furthermore, sickle bush was reported to take over the grazing lands. The bush is perceived as destructive by the Maasai community because it depletes the amount of forage for livestock grazing. It also provides suitable habitats for predators such as lions and enhances conflicts with livestock and humans.

Background: Antimicrobial resistance (AMR) is a pressing global public health issue that affects both human and animal health. Small mammals, such as rodents and shrews, represent a significant reservoir of zoonotic infections. However, there is limited documented research specifically addressing Escherichia coli and Salmonella spp. resistant strains from small mammals. Purpose: This study was conducted to examin the occurrence of AMR E. coli and Salmonella spp. and their associated resistance genes in rodents and shrews. Methods: A total of 148 fecal samples from rodents and shrews were examined for E. coli and Salmonella spp. using culture methods and biochemical tests. Fifty isolates were subjected to antibiotic susceptibility testing using the disk diffusion method on Muller-Hinton agar. Genotypic analysis by PCR was used to confirm the bacterial strains and their resistance pattern genes. Results: Two bacteria were confirmed in 57 (38.5%) of the fecal samples. Specifically, E. coli and Salmonella spp. were identified in 54 (36.5%) and 3 (2%) fecal samples, respectively. Antimicrobial susceptibility testing revealed significant resistance in Rattus rattus. Molecular analysis confirmed that Salmonella spp. carry a larger proportion of resistance genes than E. coli. Specific resistance genes, including Sul1 and Sul2, were identified, constituting 15.4% of the total resistance genes. The prevalence of β-lactamase genes was remarkable, with a higher occurrence in Salmonella spp. Conclusion: In terms of human health, the implications of rodents and shrews serving as carriers and transmitters of various pathogens were highlighted. Given the possibility of unexpected zoonoses arising from the bacteria found in this study, these findings contribute to the understanding AMR in the context of bacterial infections in animals and humans.

Background and Objectives: Mosquito-borne viral diseases (MBVDs) create a dramatic health situation worldwide. There is a need to improve the understanding of factors to be addressed in intervention programmes. This study explored community knowledge, attitudes, and practices (KAP) regarding MBVD in Kinshasa. Materials and Methods: A cross-sectional survey was carried out between January and April 2019. The socio-demographic and KAP data collected through a questionnaire were analysed using Epi Info 7. Results: The study included 1464 male and female respondents aged from 18 to 70 years old. Open garbage cans and outdoor water storage units were found in 61.2% and 33.4% of respondent residences, respectively. Polluted water bodies (80.3%) were the most mentioned as mosquito breeding places. Among 86.6% of the respondents that had heard about yellow fever, 12% knew that it is an MBVD. The majority of respondents (72.5%) were perceived to be at risk of contracting MBVD. Environment sanitation (58%) and insecticide use (25%) were among the measures implemented to control mosquitoes. The greater overall knowledge score and attitude were not associated with good practice. Conclusion: The residents of Kinshasa had limited knowledge of MBVD. Raising awareness and educational sessions are essential in empowering the community regarding the correct attitudes and practices to effectively manage the risk posed by MBVD.

Dengue is a worldwide public health concern. The current study assessed the extent of human exposure to the dengue virus in relation to the distribution pattern of Aedes aegypti and Ae. albopictus in Kinshasa. Cross-sectional surveys were carried out in 2021 and 2022. The baseline entomological survey involved 19 municipalities using a grid cell sampling approach. All containers holding water were inspected for the presence of larvae in each grid. The collected larvae were kept in an insectary until the adult emergence for morphological identification. Four hundred febrile patients attending the hospital were screened for the presence of dengue antibodies (IgG, IgM) and NS1 antigen using a rapid diagnostic test (RDT) Biosynex®. Residences of positive cases were geo-referenced. We evaluated 1850 grid cells, of which 19.5% were positive for Aedes larvae. The positive grid cells were identified in the Ndjili (44.0%), Mont Ngafula (32.0%) and Ngaliema (26.0%), and Limete (32.0%) municipalities. The Ae. aegypti (11.2%) predominated in the northwestern, and Ae. albopictus (9.1%) appeared in the high vegetation coverage areas. Of 61 (15.3%) participants exposed to dengue, 8.3% presented acute dengue. Young, (6–17 years), male, and Mont Amba district participants were most exposed to dengue. In conclusion, dengue occurrence in Kinshasa overlaps somewhat the geographical and ecological distributions of Ae. aegypti and Ae. albopictus. Both species are not homogenously distributed, likely due to environmental factors. These findings can assist the targeted control activities.

Globally, there have been calls for an integrated zoonotic disease surveillance system. This study aimed to assess human and animal health surveillance systems to identify opportunities for One Health surveillance platform in Tanzania. A desk review of policies, acts and strategies addressing disease surveillance that support inter-sectoral collaboration was conducted. A semi-structured questionnaire was administered to key informants from the two sectors. Databases with potential relevance for surveillance were assessed. One Health-focused policies, acts, strategic plans and guidelines emphasising inter-sectoral collaboration strengthening were in place. Stable systems for collecting surveillance data with trained staff to implement surveillance activities at all levels in both sectors were available. While the human surveillance system was a mix of paper-based and web-based, the animal health system was mainly paper-based. The laboratory information system existed in both sectors, though not integrated with the epidemiological surveillance systems. Both the animal and human surveillance systems had low sensitivity to alert outbreaks. The findings indicate that individual, organisational, and infrastructure opportunities that support the integration of surveillance systems from multiple sectors exist. Challenges related to data sharing and quality need to be addressed for the effective implementation of the platform.

An effective disease surveillance system is critical for early detection and response to disease epidemics. This study aimed to assess the capacity to manage and utilize disease surveillance data and implement an intervention to improve data analysis and use at the district level in Tanzania. Mapping, in-depth interview and desk review were employed for data collection in Ilala and Kinondoni districts in Tanzania. Interviews were conducted with members of the council health management teams (CHMT) to assess attitudes, motivation and practices related to surveillance data analysis and use. Based on identified gaps, an intervention package was developed on basic data analysis, interpretation and use. The effectiveness of the intervention package was assessed using pre-and post-intervention tests. Individual interviews involved 21 CHMT members (females = 10; males = 11) with an overall median age of 44.5 years (IQR = 37, 53). Over half of the participants regarded their data analytical capacities and skills as excellent. Analytical capacity was higher in Kinondoni (61%) than Ilala (52%). Agreement on the availability of the opportunities to enhance capacity and skills was reported by 68% and 91% of the participants from Ilala and Kinondoni, respectively. Reported challenges in disease surveillance included data incompleteness and difficulties in storage and accessibility. Training related to enhancement of data management was reported to be infrequently done. In terms of data interpretation and use, despite reporting of incidence of viral haemorrhagic fevers for five years, no actions were taken to either investigate or mitigate, indicating poor use of surveillance data in monitoring disease occurrence. The overall percentage increase on surveillance knowledge between pre-and post-training was 37.6% for Ilala and 20.4% for Kinondoni indicating a positive impact on of the training. Most of CHMT members had limited skills and practices on data analysis, interpretation and use. The training in data analysis and interpretation significantly improved skills of the participants.