Background: There are close similarities between the life-cycles of Echinococcus granulosus sensu lato (E. granulosus s.l.) that causes cystic echinococcosis (CE) in humans and Taenia multiceps/Coenurus cerebralis that causes cerebral coenurosis in small ruminants. Recent evidence highlights that livestock in Maasai communities of northern Tanzania are suffering from increases in the prevalence of cerebral coenurosis, leading to concerns about a possible concurrent increased risk of human CE. The aim of this study was to estimate the prevalence of human abdominal CE and the prevalence and species/genotypes of E. granulosus s.l. in livestock in Maasai communities. Methods: Human CE was diagnosed by abdominal ultrasound on volunteers aged ≥ 7 years in five villages in the Longido and Ngorongoro Districts in northern Tanzania. Infection in ruminants was evaluated through inspection in local abattoirs, followed by molecular identification of one cyst per animal, with a priority for hepatic cysts, using PCR targeting of the cytochrome c oxidase I gene (COX1), followed by restriction fragment length polymorphism and multiplex PCR, and sequencing of non-E. granulosus s.l. samples. Results: Ultrasound was performed on 823 volunteers (n = 352 in two villages in Longido District, and n = 471 in three villages of Ngorongoro). Hepatic CE cases were diagnosed only in Ngorongoro (n = 6; 1.3%), of which three had active cysts. Village-level prevalence of CE ranged between 0 and 2.4%. Of the 697 ruminants inspected, 34.4% had parasitic cysts. Molecular identification was achieved for 140 of the 219 (63.9%) cysts sampled. E. granulosus s.l. and T. hydatigena/Cysticercus tenuicollis were identified in 51.4% and 48.6%, respectively, of livestock cysts. E. granulosus s.l. was identified in livestock from both Longido (35.3% of 116 genotyped cysts) and Ngorongoro (91.2% of 34 genotyped cysts). Of the total of 72 E. granuslosus s.l. cysts identified in livestock, 87.5% were E. granulosus sensu stricto (G1–G3 genotypes), 9.7% were E. ortleppi (G5) and one cyst was E. canadensis (G6–10). The three active human cysts, which were removed surgically, were G1–G3 genotypes. Conclusions: Multiple species/genotypes of E. granulosus s.l. are circulating in Maasai communities of northern Tanzania. Human CE was detected in villages of Ngorongoro District and a high prevalence of echinococcal cysts was observed in livestock in both districts. More precise estimation of the prevalence in this area and a better understanding of the specific risk factors for CE among Maasai communities in northern Tanzania is needed. Interventions targeting transmission routes common to both E. granulosus s.l. and T. multiceps would have dual benefits for preventing both human and livestock disease. Graphical

Livestock keepers in sub-Saharan Africa face a growing range of pressures, including climate change, land loss, restrictive policies, and population increase. Widespread adaptation in response to such pressures can lead to the emergence of new, non-traditional typologies of livestock production. We sought to characterise livestock production systems in northern Tanzania, a region undergoing rapid social, economic, and environmental change. Questionnaire and spatial data were collected from 404 livestock-keeping households in 21 villages in Arusha and Manyara Regions in 2016. Multiple factor analysis and hierarchical cluster analysis were used to classify households into livestock production systems based on household-level characteristics. Indicators of vulnerability, including household-level reports of hunger, illness, livestock loss, land loss and crop losses were compared between production systems. Three distinct clusters emerged through this process. The ethnic, environmental and livestock management characteristics of households in each cluster broadly mapped onto traditional definitions of ‘pastoral’, ‘agro-pastoral’ and ‘smallholder’ livestock production in the region, suggesting that this quantitative classification system is complementary to more qualitative classification methods. Our findings also suggest that traditional systems of livestock production continue to persist in northern Tanzania. Nonetheless, we found indicators of substantial change within livestock production systems, most notably the adoption of crop agriculture in the majority of pastoral households. Smallholder households were less likely than either pastoral or agro-pastoral households to report hunger, illness, and livestock, land or crop losses. Livelihoods that rely solely on livestock are relatively rare in northern Tanzania, which represents an important shift in production in the region, particularly among pastoralists. Policy initiatives to improve household and community well-being should recognise the continuing distinctiveness of traditional livestock production systems in the region.

Coenurosis due to Taenia multiceps has emerged as a major concern to small ruminant-owning communities in northern Tanzania. Although a high incidence of disease has been reported, gaps still remain in our knowledge of the disease problem across different agro-ecological settings. The study aimed to determine the prevalence of coenurosis in small ruminants and taeniid infection in dogs and identify risk factors for infection. Questionnaire surveys, postmortem examination of small ruminants, and coproscopic examination of dog faeces were used to collect data on reported coenurosis cases and taeniid infections, respectively. The twelve-month period prevalence of coenurosis in small ruminants was 8.4% (95% CI 8.2–8.6). The prevalence of taeniid infection in dogs was 12.5% (95% CI 9.1–17.4). The village-level prevalence of coenurosis in sheep and goats was significantly correlated with taeniid infection prevalence in dogs (r = 0.51, p = 0.029). Multivariable analysis indicated that home slaughter was significantly associated with the livestock owner-reported neurological syndrome due to coenurosis in sheep and goats (OR = 13.3, 95% CI 4.2–42.0, p < 0.001) and the practice of offering discarded brains to dogs was significantly associated with taeniid infection prevalence in dogs (OR = 2.80, 95% CI 0.98–7.98, p = 0.05). Coenurosis is a major disease problem in livestock-keeping communities of northern Tanzania, but there is little awareness of transmission risks associated with home slaughter and dog feeding practices. There is a need for veterinary and animal health services to engage more actively with communities to increase awareness of the transmission cycle of T. multiceps and the preventive measures that can be taken to reduce the impact of disease in livestock-dependent communities.

Cerebral coenurosis is a fatal parasitic neurological disease affecting the brain and spinal cord of goats and sheep. Despite the large population of sheep and goats in Africa, there is very little awareness about the scale or effects of the disease. A systematic review was conducted to bridge the gap in the current understanding of the epidemiology of Taenia multiceps coenurosis in Africa. A detailed literature search was conducted in EBSCOhost, Google Scholar, Research4life (AGORA), and PubMed for studies in T. multiceps coenurosis in goats and sheep in Africa for the period spanning January 2000 to December 2019. The search identified 574 publications, of which only 11 studies were eligible, highlighting major gaps in reporting of this disease in Africa. Data were extracted and evidence synthesized in relation to prevalence and determinants for T. multiceps coenurosis. The descriptive summary statistics revealed a median (IQR) prevalence of coenurosis of 22.3% (range: 18.3–26.4 percent) for community based and 14.8% (range: 3.8–45.6) for abattoir-based studies. This high prevalence indicates that Taenia multiceps coenurosis is an important disease for small ruminant productivity in Africa. Knowledge of the determinants of prevalence could be used to inform preventive measures, including behaviour change among livestock keepers and those involved in livestock slaughter to break cycles of transmission between small ruminants and dogs.

Fasciolosis and indigestible foreign bodies (IFBs) are important causes of organ damage, condemnation and reduced carcass quality in Tanzanian slaughter facilities, highlighting persistent challenges in livestock health management, pasture hygiene, and waste management. These conditions pose significant food safety and environmental risks. A cross-sectional study was conducted at Uvinza Slaughter Slab from 1st March to 30th September, 2025 to determine the prevalence and associated risk factors for fasciolosis and IFBs. Postmortem examination of cattle assessed liver pathology and forestomach contents. Data on animal biodata, grazing system, source, presence and type of IFBs, anatomical location, and reasons for liver rejection were collected. Descriptive statistics, and logistic regression analyses were performed using R software. All slaughtered cattle (n=436) during the study period were examined. The overall prevalence of fasciolosis was 14.7% (95% Confidence interval (CI): 11.5-18.3). The prevalence of IFBs was 4.4% (95% CI: 2.8-7.0), with plastic bags and clothing materials being the most frequently encountered. Cattle with good Odds ratios (OR) = 0.17; 95% CI: 0.05-0.55; p < 0.001) and moderate (OR = 0.40; 95% CI: 0.20-0.82; p = 0.01) body condition score had significantly lower odds of fasciolosis compared to those with poor body condition. No significant predictors were identified for IFBs, suggesting that their occurrence is primarily driven by environmental factors. Fasciolosis and IFBs remain the major causes of organ damage, condemnation, economic loss, and food safety risks in Uvinza. The IFBs reflect the growing environmental pollution and inadequate waste management. Strengthened community engagement, participatory programs and extension systems on deworming and waste management under a One Health framework are essential for effective control.