Brucellosis in West and Central Africa: A review of the current situation in a changing landscape of dairy cattle systems

Exploring the Complex Landscape of Spine Brucellosis

INTRODUCTION

Brucellosis is an infectious illness contracted by humans through the consumption of unpasteurized milk and dairy items. Brucella organisms are diminutive, gram-negative, non-motile, and non-spore-forming facultative intracellular, aerobic intracellular coccobacilli residing within the reproductive organs of host animals, leading to conditions such as abortions and sterility. Numerous species of Brucella have been identified, with the following four exhibiting varying degrees of pathogenicity in humans: Brucella melitensis (originating from sheep), Brucella suis (associated with pigs), Brucella abortus (linked to cattle), and Brucella canis (found in dogs). B. melitensis and B. suis demonstrate the highest level of pathogenicity, while B. abortus and B. canis exhibit a more moderate degree of pathogenicity. The illness can progress to systemic involvement, with the musculoskeletal system being particularly susceptible to complications. Spinal epidural abscess is an infrequent complication that may occur during spondylitis caused by Brucella species. Epidural abscesses most commonly affect the lumbar vertebrae, while their involvement in the cervical spine is relatively rare.

OBJECTIVE

In this review, we explore spine brucellosis, covering its epidemiology, pathogenesis, clinical manifestations, diagnostics, and evolving treatments. We aim to enhance early detection, timely intervention, and patient outcomes.

PATIENTS AND METHODS

This retrospective chart analysis was conducted by revising all medical files for patients in whom spinal brucellosis was diagnosed and managed.

RESULTS

This study was conducted at King Hussein Medical Center (KHMC), Jordan, and included a total of 20 patients who were diagnosed with spine brucellosis during the study period. Within the final cohort, 65% of the patients were male (13/20), with an average age at diagnosis of 47.53±14.98 years (ranging from 4 to 61 years). The female group, on the other hand, had an average age at diagnosis of 51.12±15.55 years (ranging from 3 to 58 years). Statistical analysis of the data revealed no significant demographic differences between the two groups. Regarding the co-morbidities, no statistical differences were observed between the two groups. Examining the occupational status of the two groups, no differences were observed. Also, no differences were observed between the two groups regarding the residence place, or the spinal segment involved.

CONCLUSION

Spine brucellosis, although uncommon, poses a complex clinical challenge. Early diagnosis and a multidisciplinary approach are crucial for effective management. Further research is needed to refine diagnostic tools and treatment guidelines for spine brucellosis.

Nutritional Value of Climate-Resilient Forage Species Sustaining Peri-Urban Dairy Cow Production in the Coastal Grasslands of Benin (West Africa)

Along the coast of West Africa, grazing ruminants rely on perennial forage species remaining in uncultivated plots, roadsides, and marshlands during the dry season. To assess the quality of these forages, thirteen drought-tolerant plants were harvested at the mature stage, and the samples were evaluated for chemical composition, in vitro fermentation characteristics, and metabolizable energy (ME) content. They are ten drought-tolerant grasses, including: Andropogon virginicus, Brachiaria deflexa, Cenchorus biflorus, Dactyloctenium aegyptium, Eragrostis tremula, Leptochloa caerulescens, Loudetia aroundinacea, Paspalum notatum, Paspalum vaginatum, Pennisetum purpureum, two perennial herbs, Chamaecrista rotundifolia, Zornia latifolia, and one multipurpose tree, Elaeis guineensis. Legume species had the highest nutritional value (highest crude protein and ME, and lowest neutral detergent fiber) of the species studied. In terms of the in vitro data, the gas produced after 120 h of incubation ranged from 149 mL/g in E. tremula to 185 mL/g in Paspalum. Z. latifoliaa and had the fastest rate of fermentation, producing half of the total gas in 19.5 h, whereas E. tremula required 49.9 h (p < 0.01). The production of branched-chain fatty acids (isobutyrate and isovalerate) was greatest for E. guineensis and the lowest in both Paspalum species (p < 0.01). The study suggests the need for the protein supplementation of the animals to ensure maximum forage utilization and to satisfy the nutrient requirements of ruminant livestock.

Insights into the diversity of cow milk production systems on the fringes of coastal cities in West Africa: A case study from Benin

In sub-Saharan Africa, rapid population growth, urbanization, increasing incomes, and changing dietary preferences are the main drivers of the rising demand for livestock products, especially fresh milk and derived products. To meet this demand, there is an increasing number of dairy cattle farms in the densely populated coastal zone of Benin, where the country's largest city and commercial capital Cotonou is located. To identify and characterize the peri-urban dairy production systems in this region, 190 cattle keepers were surveyed, using the snowball sampling method, in four municipalities neighboring Cotonou. Information on their socio-economic characteristics, cattle herd sizes, and herd management practices were collected through questionnaire-based face-to-face interviews. Factor analysis of mixed data followed by hierarchical clustering on principal components, implemented in R statistical software, were applied to classify the surveyed farms into homogeneous groups. Results revealed six types of peri-urban dairy cattle farms differing mainly in their cows' breeds, herd sizes, and daily amount of milk produced. Most herds (88%) were owned by urban dwellers, mainly civil servants and traders, who entrusted the management of their cattle to hired professional herders. Irrespective of farm type, cows were of local taurine (65%) or Sahelian zebu (35%) breeds and were exclusively fed on communal natural pasture. Mineral supplementation was provided to the animals on 42% of farms, with significant variation across farm types. About 45% of the farms integrated cattle production with other agricultural activities, including coconut plantations (22%), where cow manure was used as fertilizer. The herd structure was similar across farm types, with average proportions of cows and heifers ranging from 37.6 to 47.5% and from 13.1 to 19.7%, respectively. With significant differences across farm types, the produced milk was either transformed into traditional cheese (32% of farms) or sold raw (85%). Milk and cheese sales represented 84% of the total farm income for three out of the six farm types. In the current context of rapid urbanization, communal grazing lands alone cannot provide sufficient feed to support increased milk production. In addition to improved feeding strategies, herd structure should be balanced in terms of the ratio between milk-producing and non-producing animals.

Investigation of a human brucellosis outbreak in Douz, Tunisia, 2018

OBJECTIVES

In 2017, the incidence of human brucellosis in Tunisia was 9.8 per 100,000 population. In the Douz district, 2 cases were reported in March 2018. Prior to that date, the last indigenous cases to be reported in Douz had been in 2015. This study aimed to identify the source of this new contamination and recommend control interventions.

METHODS

This case-control study included residents of Douz who presented with clinical symptoms of brucellosis and had a subsequent Wright test antibody titer ≥ 1/160. The controls were neighbors of the infected cases who had a negative Rose Bengal test. Univariate and multivariate analyses were performed to estimate the odds ratios of risk factors. Goats belonging to the cases and controls were actively screened.

RESULTS

Twenty-five infected cases and 52 uninfected controls were enrolled. All infected cases had consumed goat milk and 92% had purchased it from the same breeder. Consumption of goat milk from this breeder (adjusted odds ratio [aOR], 30.78; 95% confidence interval [CI], 6.47 to 235.91) and overall consumption of raw goat milk (aOR, 14.84; 95% CI, 2.04 to 310.44) were independent risk factors for brucellosis. The breeder had 18 goats, 5 of which were smuggled from a neighboring country. Three of those goats were diagnosed with brucellosis.

CONCLUSIONS

Consumption of raw milk from smuggled sick goats was the main risk factor in this outbreak. The sick goats were slaughtered and an education campaign was conducted. Vaccination, control of cross-border animal movements, and control of goat milk sales must be strengthened to prevent the spread of brucellosis in southwestern Tunisia.

Brucellosis: Prevalence with reference to East African community countries - A rapid review

Brucellosis is a zoonotic disease which is endemic to certain regions of the world including Sub-Saharan Africa. The aim of this article is to provide a recent and rapid review on brucellosis prevalence in East African Community (EAC) countries. Literature was obtained using Google Scholar search engine and screened for relevancy and fulfilment of criteria to 1, 17, 4, 4, 30 and 29 articles retained for brucellosis prevalence in Burundi, Kenya, Rwanda, South Sudan, Tanzania and Uganda. Recent literature (published in the last decade 2010 to 2019) was considered for prevalence results in this review. In EAC, livestock had an animal-level prevalence of 0.2% to 43.8%, 0.0% to 20.0% and 0.0% to 13.8% for cattle, goats and sheep respectively. In humans, the prevalence varied mostly between 0.0% and 35.8%. In conclusion, brucellosis is quite prevalent in the region. The reported prevalence calls for plans or more efforts from individual member countries and from EAC, as a region, to control brucellosis.

Brucellosis in dairy herds: Farm characteristics and practices in relation to likely adoption of three potential private-public partnership (PPP) vaccination control strategies in West and Central Africa

Brucellosis is regarded as one of the highest burden zoonotic diseases to persist in many regions globally. While sustained vaccination against B. abortus in an endemic setting can markedly reduce the prevalence of large ruminant and human brucellosis and benefit local livelihoods, the implementation of effective and sustainable control programmes has often failed in the worst affected areas. In a cross-sectional study of 728 peri-urban dairy farmers in nine areas of six West and Central African countries, levels of commercialization and farm characteristics were examined alongside B. abortus seroprevalence estimates to hypothesize the most appropriate model for brucellosis vaccination delivery in each country. Demographic and economic data were collated and used to describe the farming systems currently in place. Furthermore, these data were utilized in a likelihood assessment to generate a quantitative score to hypothesize which of three private-public partnership (PPP) vaccine delivery models, that is 1) transformative, 2) transactional or 3) collaborative, would be most appropriate in each setting. The study sites had substantial differences in their levels of dairy commercialization and the farming practices employed; the heterogeneity across the study sites was evident in the conclusions of which models would be appropriate for vaccination delivery. While Lomé (Togo) had a strong indication for a transformative PPP model, Burkina Faso had strong indication for the collaborative PPP model. Of the remaining study sites, the scores were less dominant for any one model with Cameroon and Ivory Coast sites only just scoring highest on the transformative model and Senegal and Mali sites only just scoring highest on the collaborative model. Interestingly, none of the countries included in the study scored highest on the transactional model which currently is the most commonplace delivery model in the majority of sub-Saharan African countries.

Prioritizing smallholder animal health needs in East Africa, West Africa, and South Asia using three approaches: Literature review, expert workshops, and practitioner surveys

Managing the health needs of livestock contributes to reducing poverty and improving the livelihoods of smallholder and pastoralist livestock keepers globally. Animal health practitioners, producers, policymakers, and researchers all must prioritize how to mobilize limited resources. This study employed three approaches to prioritize animal health needs in East and West Africa and South Asia to identify diseases and syndromes that impact livestock keepers. The approaches were a) systematic literature review, b) a series of expert workshops, and c) a practitioner survey of veterinarians and para-veterinary professionals. The top constraints that emerged from all three approaches include endo/ ectoparasites, foot and mouth disease, brucellosis, peste des petits ruminants, Newcastle disease, and avian influenza. Expert workshops additionally identified contagious caprine pleuropneumonia, contagious bovine pleuropneumonia, mastitis, and reproductive disorders as constraints not emphasized in the literature review. Practitioner survey results additionally identified nutrition as a constraint for smallholder dairy and pastoralist small ruminant production. Experts attending the workshops agreed most constraints can be managed using existing veterinary technologies and best husbandry practices, which supports a shift away from focusing on individual diseases and new technologies towards addressing systemic challenges that limit access to veterinary services and inputs. Few research studies focused on incidence/ prevalence of disease and impact, suggesting better incorporation of socio-economic impact measures in future research would better represent the interests of livestock keepers.

"Everything in this world has been given to us from cows", a qualitative study on farmers' perceptions of keeping dairy cattle in Senegal and implications for disease control and healthcare delivery

The dairy industry in Senegal is growing and evolving against a backdrop of rapid urbanisation and increasing consumer demand for dairy products. Consideration of appropriate cattle healthcare delivery and disease control in these evolving farming systems is of paramount importance given the risks posed by zoonotic pathogens and the economic consequences of disease for livestock keepers. Planning and implementation of disease control and healthcare delivery generally follows a top down approach. Often this does not take into account the views and perceptions of the farmers it impacts and who must behave in the expected way for successful outcomes to materialise. In this study, we asked 76 farmers to discuss their experience and opinions of farming milk producing cattle in 11 focus group discussions conducted in two peri-urban areas of Senegal. The objectives were to investigate farmers’ perceptions of the current conditions in farming, to understand how these might impact the future direction of this particular system and how this might affect the feasibility and appropriate methods of cattle healthcare delivery and disease control. The data collected were subjected to thematic analysis and four themes were identified; 1. Revered cattle, 2. The changing face of livestock keeping, 3. Powerlessness, 4. Optimism for the future. Farmers in our study had a deep affinity with their cattle, they respected the traditions surrounding cattle keeping at the same time as striving for advances within the system and their animal’s productivity. Within strong social groupings and hierarchical structures they recognised the inherent challenges they face but were hopeful and optimistic about growth and opportunity in the future of milk production. A holistic approach to embedding healthcare delivery and disease control within the broader context in which farmers operate may prove successful. This could involve consideration of funding channels for farmers, access to appropriate inputs and utilising the strong community spirit and social norms of farmers to initiate and facilitate change.

Brucellosis in dairy herds: A public health concern in the milk supply chains of West and Central Africa

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Brucellosis is endemically established among dairy herds in West and Central Africa.

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Brucella spp. infection is present at high levels in dairy herds in Lomé and Bamako.

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Brucellosis poses a public health concern in dairy chains of West and Central Africa.

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Brucellosis control programs are urgently needed in West and Central Africa.

Ten herd-level cross-sectional studies were conducted in peri-urban dairy production areas of seven West and Central African countries (Burkina Faso, Burundi, Cameroon, Mali, Niger, Senegal and Togo). The objectives were to estimate herd level Brucella spp. seroprevalence and identify risk factors for seropositivity.

In each of the ten study areas, herds (between 52 and 142 per area, total = 965) were selected probabilistically and a structured questionnaire was administered to gather information on their structure and management. A bulk milk sample from each herd was tested by indirect ELISA for Brucella spp. For each area, herd seroprevalence estimates were obtained after adjusting for the assumed performance of the diagnostic test. Herd level risk factors for Brucella spp. seropositivity were identified by means of stratified logistic regression, with each peri-urban zone as a stratum. Area-specific models were also explored.

Estimated herd seroprevalences were: Lomé (Togo) 62.0% (95% CI:55.0–69.0), Bamako (Mali) 32.5% (95% CI:28.0–37.0), Bujumbura (Burundi) 14.7% (95%CI:9.4–20.8), Bamenda (Cameroon) 12.6% (95% CI:7.6–21.9), Ouagadougou (Burkina Faso) 3.0% (95% CI:1.0–9.1), Ngaoundere (Cameroon) 2.3% (95% CI:1.0–7.0), Thies (Senegal) 1.3% (95% CI:0.1, 5.3), Niamey (Niger) 1.2% (95% CI:0.08-5.3), Dakar (Senegal) 0.2% (95% CI:0.01–1.7) and Niakhar (Senegal) <0.04%. Logistic regression modelling revealed transhumant herds to be at lower risk of infection (adjusted OR: 0.25, 95% CI: 0.13 - 0.5) and in one of the areas (Bamenda), regular purchase of new animals was found to be strongly associated with Brucella spp. seropositivity (adjusted OR = 5.3, 95% CI: 1.4–25.9). Our findings confirm that Brucella spp. circulates among dairy cattle supplying milk to urban consumers in West and Central Africa, posing a serious public health concern. Control programs are urgently needed in areas such as Lomé or Bamako, where more than 30% of the herds show evidence of infection.

Reasons behind the epidemiological situation of brucellosis in the Republic of Kazakhstan

Brucellosis is endemic in the Republic of Kazakhstan, particularly in agro-pastoral areas. The purpose of this research is to study the epidemiological situation of brucellosis in livestock recorded in the Republic of Kazakhstan, and to identify the reasons why anti-brucellosis measures were not effective. The research was performed on statistical data provided by the Republican Veterinary Laboratory (RVL), the Ministry of Agriculture of the Republic of Kazakhstan. The analysis touched upon the prevalence of Brucellosis in cattle and small ruminants (sheep and goats) in 13 regions of the Republic of Kazakhstan in 2012-2016. Aside from that, Research Institute for Biological Safety Problems conducted screening assays that involved 11,889 samples of blood and tissues from said animals. The risks of developing Brucellosis were assessed for each particular region. The comparison of studies conducted in 2012-2016 reveals an increase in the prevalence of Brucellosis in cattle in the following regions: West Kazakhstan, Karaganda Region and Pavlodar Region. For small ruminants, growing prevalence was observed in the Kostanay Region, Jambyl Region and Almaty Region. Between 2014 and 2016, the incidence rate had a growing trend, with a high in 2014 and 2015. The lowest prevalence rate during the following years (2012-2016) was in the Mangystau Region. The Enzyme-Linked Immunosorbent Assay (ELISE) test applied in the research among other tests provided the best results. The main risk factors involve epidemiology and sanitary measures, which are undertaken in the Republic of Kazakhstan, geography of the region with focuses of infection, and randomness of spread.

Emergency response to occupational brucellosis in a pharmaceutical manufacturing enterprise

Objectives:

Human brucellosis, as a zoonosis, is a serious public health problem in many developing countries, including China. To date, there has been no case report on occupational brucellosis and the emergency response in the pharmaceutical manufacturing industry. The aim of this report is to describe an emergency brucellosis outbreak in this unusual setting and the associated treatment methods from an occupational health perspective.

Methods:

The emergency response included a field epidemiological investigation, a hierarchy of control strategy, and validation of control measures.

Results:

Seven workers in the defrosting, grinding, and hydrolysis departments suffered from human brucellosis during two periods. The main symptoms were whole-body joint pain and undulant fever for several weeks, and Brucella-specific serum antibody was found in the patients. A hierarchy of exposure control strategy was implemented, including elimination, engineering control, administrative control, and the use of personal protection equipment. Raw material and environmental monitoring, measurement of placental temperature, Escherichia coli inactivation tests, and health examinations demonstrated that these measures were effective.

Conclusions:

This report describes an emergent case and the response to two consecutive outbreaks of occupational brucellosis among workers in a pharmaceutical manufacturing enterprise. The hierarchical control strategy used in this case may prevent new outbreaks, and several lessons can be learned from this event.

Trends of reported human brucellosis cases in mainland China from 2007 to 2017: an exponential smoothing time series analysis

BACKGROUND

The main objective of this study was to describe the temporal distribution of monthly reported human brucellosis cases in mainland China and develop an appropriate time series model for short-term extrapolation forecast.

METHODS

Surveillance data of the monthly reported human brucellosis cases occurring from April 1, 2007, to March 31, 2017, in mainland China were obtained. The spectrum analysis was first adopted to find the cyclic and seasonal features, the existence of the seasonality and trend was determined by exponential smoothing method and the seasonal-trend decomposition. The candidate models of exponential smoothing included the additive model and multiplicative model; R² was selected as the indicator for the selection of candidate model, and the stability of the model was verified by adjusting the training data and test data set. Finally, the extrapolations of monthly incident human brucellosis cases in 2017 were made.

RESULTS

From April 1, 2007, to March 31, 2017, a total of 435,108 cases of Brucellosis occurred in mainland China were reported, with an average of 3626 cases per month and a standard deviation of 1834 cases. The R² of the exponential smoothing method that based on additive model increased steadily from 0.927 to 0.949 with the increase of the data volume. Ten of 12 actual values fell in the confidence interval of predicted value.

CONCLUSIONS

Human brucellosis cases peaked during the months from March to August in mainland China, with clear seasonality. The exponential smoothing based on the additive model method could be effectively used in the time series analysis of human brucellosis in China. Control methods, such as vaccination, quarantine, elimination of infected animals, and good hygiene within the production cycle, should be strengthened with paying more attention to the seasonality. Further research is warranted to explore the drivers behind the seasonality.