Bacillus anthracis, the bacteria that causes anthrax, a disease that primarily affects herbivorous animals, is a soil borne endospore-forming microbe. Environmental distribution of viable spores ...determines risky landscapes for herbivore exposure and subsequent anthrax outbreaks. Spore survival and longevity depends on suitable conditions in its environment. Anthrax is endemic in Queen Elizabeth Protected Area in western Uganda. Periodic historical outbreaks with significant wildlife losses date to 1950s, but B. anthracis ecological niche in the ecosystem is poorly understood. This study used the Maximum Entropy modeling algorithm method to predict suitable niche and environmental conditions that may support anthrax distribution and spore survival. Model inputs comprised 471 presence-only anthrax occurrence data from park management records of 1956-2010, and 11 predictor variables derived from the World Climatic and Africa Soil Grids online resources, selected considering the ecology of anthrax. The findings revealed predicted suitable niche favoring survival and distribution of anthrax spores as a narrow-restricted corridor within the study area, defined by hot-dry climatic conditions with alkaline soils rich in potassium and calcium. A mean test AUC of 0.94 and predicted probability of 0.93 for anthrax presence were registered. The five most important predictor variables that accounted for 93.8% of model variability were annual precipitation (70.1%), exchangeable potassium (12.6%), annual mean temperature (4.3%), soil pH (3.7%) and calcium (3.1%). The predicted suitable soil properties likely originate from existing sedimentary calcareous gypsum rocks. This has implications for long-term presence of B. anthracis spores and might explain the long history of anthrax experienced in the area. However, occurrence of suitable niche as a restricted hot zone offers opportunities for targeted anthrax surveillance, response and establishment of monitoring strategies in QEPA.
•Bacillus anthracis spore persistence in Tanzania depends on the soil type and soil pH (alkalinity).•Bioclimatic variables are significant variables for the distribution of B. anthracis spores in ...Tanzania.•Northern Tanzania has a high risk of anthrax outbreaks in humans, livestock, and wildlife species.•A One Health approach is needed to control episodes of anthrax outbreaks in Tanzania.
Anthrax is caused by the spore-forming, Gram-positive bacterium Bacillus anthracis. The aim of this study was to predict the potential distribution of B. anthracis in Tanzania and produce epidemiological evidence for the management of anthrax outbreaks in the country.
The Maxent algorithm was used to predict areas at risk of anthrax outbreaks based on the occurrence and environmental data in Arusha and Kilimanjaro regions; the model was later transferred to predict the entire country. Seventy percent of the occurrence data were used to train the model, while 30% were used for model evaluation.
Four regions of northern Tanzania are predicted to have a high risk for anthrax outbreaks, while the southern and western regions had low-risk areas. Soil type (56.5%), soil pH (23.7%), and isothermally (10.4%) were the most important variables for the model prediction, and the most significant soil types were solonetz, fluvisols, and lithosols.
A strong risk level across districts of the Tanzania mainland was identified in this study. A total of 18 districts in Tanzania Mainland are predicted to be at very high risk of an anthrax outbreak occurrence. These findings are important for policymakers to effectively mount targeted control measures for anthrax outbreaks in Tanzania.
All infections are potentially curable as long as the etiological agents are susceptible to antimicrobials. The increased rate at which antimicrobials are becoming ineffective is a global health risk ...of increasing concern that threatens withdrawal of beneficial antimicrobials for disease control. The increased demand for food of animal origin, in particular eggs, meat and milk has led to intensification and commercial production systems where excessive use and misuse of antimicrobials may prevail. Antimicrobials, handled and used by farmers and animal attendants with no formal education, may be predisposed to incorrect dosages, misuse, incorrect applications and non-adherence to withdrawal periods. This study was conducted to assess the regulatory roles and governance of antimicrobials, establish the pattern and extent of their use, evaluate the antimicrobial residues and resistance in the food animals and crop agriculture value chains, and relate these findings to existing strategies in place for combating the emergence of antimicrobial resistance in Tanzania. A multimethod approach (desk review, field study and interviews) was used. Relevant establishments were also visited. High levels of resistance to penicillin G, chloramphenicol, streptomycin and oxytetracycline have been reported, especially for
,
,
and
from dairy cattle with mastitis and in humans. Similar trends were found in poultry where eggs and meat are contaminated with
strains resistant to amoxicillin + clavulanate, sulphamethoxazole and neomycin. An increasing trend of emerging multidrug resistant
,
,
and
was also found in food animals. An increase in methicillin resistant
(MRSA) and extended-spectrum beta-lactamase (ESBL) in the livestock sector in Tanzania have been reported. The pathogens isolated in animals were resistant to ampicillin, augmentin, gentamicin, co-trimoxazole, tetracycline, amoxicillin, streptomycin, nalidixic acid, azithromycin, chloramphenicol, tylosin, erythromycin, cefuroxime, norfloxacin and ciprofloxacin. An increased usage of antimicrobials for prophylaxis, and therapeutics against pathogens and for growth promotion in livestock, aquaculture and crop production were observed. A One Health strategic approach is advocated to combat antimicrobial resistance (AMR) in the food and agriculture sectors in Tanzania. Practical recommendations include (a) legislation review and implementation; (b) antimicrobial use (AMU), AMR and antimicrobial residue (AR) awareness and advocacy among stakeholders along the value chain; (c) strengthening of surveillance and monitoring programs for AMU, AMR and AR; (d) enhanced development and use of rapid and innovative diagnostic tests and the promotion of biosecurity principles; and (e) good husbandry practices. The utilization of this information to improve public health policies and reduce the burden of AMR will be beneficial.
Animal health service providers can play an important role in limiting drug resistance by promoting responsible and prudent use of veterinary drugs. Recognizing this potential, international agencies ...and governments have called for these providers to receive drug stewardship training, particularly providers in low- and middle-income countries where top-down regulations (e.g., national regulation of veterinary prescriptions) are largely unfeasible. The success of these stewardship trainings to promote responsible and prudent use will depend on many factors, including understanding how livestock-keeping communities currently interact with animal health service providers. Here, we use a mixed methods approach to identify and understand animal health seeking practices among Maasai pastoralists in Tanzania. Combining qualitative interviews (N = 31) and structured surveys (N = 195), we show the majority of Maasai respondents (≈80 %) do not frequently consult animal health service providers with most relying on advice from family and friends. Logistic regression models of health seeking practices find that increasing age, education, observance of treatment failure, and herd disease burdens are associated with greater odds of seeking out health services. Quantitative results were supported by data from focus group discussions and in-depth interviews that showed Maasai view animal health service providers as measures of last resort, whose input is largely sought after self-treatment with veterinary drugs fail. We argue patterns of animal health seeking among the Maasai are partially the consequence of their high confidence in their own abilities in livestock disease and treatment and generally low confidence in the skills of animal health service providers. We link this high sense of self-efficacy to the culturally engrained process by which Maasai develop mastery in animal health and how the roles and norms in Maasai culture surrounding animal health influence Maasai perceptions of animal health professionals. Our results highlight the need for more research to understand Maasai perceptions of animal health service providers as well as the knowledge, attitudes, and practices of these providers. Finally, our study emphasizes that the success of drug stewardship trainings will require efforts to first understand the cultural and historical contexts driving health seeking practices that impact perceptions of animal health service providers and animal health practices more generally.
Global, national, and local efforts to limit antimicrobial resistance (AMR) often stress the importance of raising awareness among users, sellers, and prescribers of antimicrobial drugs. This ...emphasis is founded upon two assumptions. First, awareness is limited, particularly concerning the links between antimicrobial use (AMU) and AMR. Second, "filling the awareness gaps" will motivate practises that will limit AMR. The first assumption is supported by knowledge, attitudes, and practises (KAP) surveys but these same studies provide mixed support for the second, with several studies finding that knowledge and attitudes are not correlated with related practises. This disconnect may arise as these surveys typically do not collect data on the cultural or historical contexts that pattern AMU. To explore how these contexts impact KAP related to AMU and AMR, we use a mixed-methods approach to examine veterinary practises among Maasai pastoralists in Tanzania. We combine a quantitative KAP survey (
= 195 households) with extensive qualitative data from focus group discussions (
= 55 participants). Results document limited awareness of AMR but also find that knowledge and attitudes are not correlated with practise. Thematic analysis of qualitative data pointed to three reasons behind this disconnect, including (1) Maasai self-perceptions as veterinary experts, (2) the central role of livestock in Maasai culture, and (3) the use of ethnoveterinary knowledge in animal health treatment. We argue that mixed-method approaches will be critical to developing the targeted awareness campaigns needed to limit the emergence and transmission of AMR.
IntroductionAwareness-raising campaigns play a central role in efforts to combat drug resistance. These campaigns assume that knowledge deficits drive poor practices that increase resistance. ...Therefore, increasing awareness will promote prudent practices and reduce resistance. However, most awareness campaigns have been developed and evaluated in high-income and public health settings. Consequently, it is not clear whether these campaigns are effective in low-income and middle-income countries and/or within animal health settings.MethodsFocus group discussions and in-depth interviews were used to collect narratives of veterinary drug use among Maasai pastoralists (n=70), animal health professionals (n=10) and veterinary drug sellers (n=5). Thematic analysis was used to identify recurring themes across narratives and groups.ResultsNarratives of Maasai and animal health professionals indicated that Maasai treated their livestock with limited input from the professional sector and that non-prudent treatment practices were observed (eg, using antimicrobials as ‘energizers’). Professionals linked these practices to knowledge and attitudinal deficits among the Maasai, while Maasai narratives highlighted the importance of climatic uncertainties and cultural beliefs surrounding veterinary care.ConclusionNarratives of veterinary drug use from animal health professionals are consistent with the knowledge deficit assumption guiding awareness-raising efforts. In contrast, Maasai narratives highlight how animal health practices are patterned by cultural norms interacting with factors largely outside of Maasai control, including a constrained professional veterinary sector. If these cultural and structural contexts remain unconsidered in awareness-raising strategies, current campaigns are unlikely to motivate practices necessary to limit drug resistance, especially within low-income and middle-income settings.
The USAID Preparedness and Response (P&R) project's publication on Multisectoral Coordination that Works identified five dimensions most critical to creating effective and sustainable One Health ...platforms: political commitment, institutional structure, management and coordination capacity, technical and financial resources, and joint planning and implementation. This case study describes Tanzania experience in using these dimensions to establish a functional One Health platform. The main objective of this case study was to document the process of institutionalizing the One Health approach in Tanzania.
An analysis of the process used to establish and institutionalize the MCM in Tanzania through addressing the five dimensions mentioned above was conducted between August 2018 and January 2019. Progress activity reports, annual reports and minutes of meetings and consultations regarding the establishment of the Tanzania national One Health platform were examined. Relevant One Health publications were studied as reference material.
This case study illustrates the time and level of effort required of multiple partners to build a functional multi-sectoral coordinating mechanism (MCM). Key facilitating factors were identified and the importance of involving policy and decision makers at all stages of the process to facilitate policy decisions and the institutionalization process was underscored. The need for molding the implementation process using lessons learnt along the way -- "sailing the ship as it was being built" -- is demonstrated.
Tanzania now has a functioning and institutionalized MCM with a sound institutional structure and capacity to prevent, detect early and respond to health events. The path to its establishment required the patient commitment of a core group of One Health champions and stakeholders along the way to examine carefully and iteratively how best to structure productive multisectoral coordination in the country. The five dimensions identified by the Preparedness and Response project may provide useful guidance to other countries working to establish functional MCM.
Bacillus anthracis is an aerobic, Gram-positive and spore-forming bacterium, which causes anthrax in herbivores. Humans get infected after coming into contact with infected animals' products. An ...unmatched case–control study was conducted to identify the importance of demographic, biological and/or behavioural factors associated with human cutaneous anthrax outbreaks in the hotspot areas of Northern Tanzania. A semi-structured questionnaire was administered to both cases and controls. The age range of participants was 1–80 years with a median age of 32 years. In the younger group (1–20 years), the odds of being infected were 25 times higher in the exposed group compared to the unexposed group (OR= 25, 95% CI = 1.5–410). By contrast, the odds of exposure in the old group (≥20 years) were three times lower in the exposed group compared to the unexposed group (OR = 3.2, 95% CI = 1.28–8.00). Demographic characteristics, sleeping on animal's skins, contacting with infected carcasses through skinning and butchering, and not having formal education were linked to exposure for anthrax infection. Hence, a One Health approach is inevitable for the prevention and control of anthrax outbreaks in the hotspot areas of Northern Tanzania.
During 2014, Africa reported more than half of the global suspected cholera cases. Based on the data collected from seven countries in the African Cholera Surveillance Network (Africhol), we assessed ...the sensitivity, specificity, and positive and negative predictive values of clinical cholera case definitions, including that recommended by the World Health Organization (WHO) using culture confirmation as the gold standard. The study was designed to assess results in real-world field situations in settings with recent cholera outbreaks or endemicity. From June 2011 to July 2015, a total of 5,084 persons with suspected cholera were tested for
in seven different countries of which 35.7% had culture confirmation. For all countries combined, the WHO case definition had a sensitivity = 92.7%, specificity = 8.1%, positive predictive value = 36.1%, and negative predictive value = 66.6%. Adding dehydration, vomiting, or rice water stools to the case definition could increase the specificity without a substantial decrease in sensitivity. Future studies could further refine our findings primarily by using more sensitive methods for cholera confirmation.
Background: Anthrax is an infectious fatal zoonotic disease caused by Bacillus anthracis. Anthrax outbreak was confirmed in samples of wild animals following rumors of the outbreak in wild animals, ...livestock, and humans in Selela ward, Monduli district of Northern Tanzania. Therefore, a multi-sectorial team was deployed for outbreak response in the affected areas. Objectives: The aim of the response was to manage the outbreak in a One Health approach and specifically: (i) To determine the magnitude of anthrax outbreak in humans, livestock, and wild animals in Selela ward, (ii) to assess the outbreak local response capacity, (iii) to establish mechanisms for safe disposal of animal carcasses in the affected areas, and (iv) to mount effective control and preventive strategies using One Health approach in the affected areas. Materials and Methods: This was a cross-sectional field survey using: (i) Active searching of suspected human cases at health facilities and community level, (ii) physical counting and disposal of wild animal carcasses in the affected area, (iii) collection of specimens from suspected human cases and animal carcasses for laboratory analysis, and (iv) meetings with local animal and human health staff, political, and traditional leaders at local levels. We analyzed data by STATA software, and a map was created using Quantum GIS software. Results: A total of 21 humans were suspected, and most of them (62%) being from Selela ward. The outbreak caused deaths of 10 cattle, 26 goats, and three sheep, and 131 wild animal carcasses were discarded the majority of them being wildebeest (83%). Based on laboratory results, three blood smears tested positive for anthrax using Giemsa staining while two wildebeest samples tested positive and five human blood samples tested negative for anthrax using quantitative polymerase chain reaction techniques. Clinical forms of anthrax were also observed in humans and livestock which suggest that wild animals may contribute as reservoir of anthrax which can easily be transmitted to humans and livestock. Conclusion: The rapid outbreak response by multi-sectoral teams using a One Health approach managed to contain the outbreak. The teams were composed of animal and human health experts from national to village levels to control the outbreak. The study testifies the importance of multi-sectoral approach using One Health approach in outbreak preparedness and response.
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