Brucellosis in terrestrial wildlife

The epidemiological link between brucellosis in wildlife and brucellosis in livestock and people is widely recognised. When studying brucellosis in wildlife, three questions arise: (i) Is this the result of a spillover from livestock or a sustainable infection in one or more host species of wildlife? (ii) Does wildlife brucellosis represent a reservoir of Brucella strains for livestock? (iii) Is it of zoonotic concern? Despite their different host preferences, B. abortus and B. suis have been isolated from a variety of wildlife species, whereas B. melitensis is rarely reported in wildlife. The pathogenesis of Brucella spp. in wildlife reservoirs is not yet fully defi ned. The prevalence of brucellosis in some wildlife species is very low and thus the behaviour of individual animals, and interactions between wildlife and livestock, may be the most important drivers for transmission. Since signs of the disease are non-pathognomonic, defi nitive diagnosis depends on laboratory testing, including indirect tests that can be applied to blood or milk, as well as direct tests (classical bacteriology and methods based on the polymerase chain reaction [PCR]). However, serological tests cannot determine which Brucella species has induced anti-Brucella antibodies in the host. Only the isolation of Brucella spp. (or specifi c DNA detection by PCR) allows a defi nitive diagnosis, using classical or molecular techniques to identify and type specifi c strains. There is as yet no brucellosis vaccine that demonstrates satisfactory safety and effi cacy in wildlife. Therefore, controlling brucellosis in wildlife should be based on good management practices. At present, transmission of Brucella spp. from wildlife to humans seems to be linked to the butchering of meat and dressing of infected wild or feral pig carcasses in the developed world, and infected African buffalo in the developing world. In the Arctic, the traditional consumption of raw bone marrow and the internal organs of freshly killed caribou or reindeer is an important risk factor.bacteriologyBrucella sppBrucellosisEpidemiologyLivestock/wildlife interfaceSerologyWildlifePublishe

Structure-activity relationships on adrenoceptors and imidazoline-preferring binding sites (I(1,2)-PBSs). Part 1: Weak intramolecular H-bond and conformational flexibility in a new I1-PBS-selective imidazoline analogue, trans1-(4',5'-dihydro-1'H-imidazol-2'-yl)methyl-2-hydroxyindane (PMS 952).

The highly selective I1-PBS imidazoline analogue PMS 952 has been selected to study the incidence of intramolecular hydrogen bond and molecular flexibility on its biological activity. On one hand, the weak energy difference between three calculated conformers does not support the stabilization of one conformer by an internal hydrogen bond. The 3-D electrostatic map confirms this feature and the solvent effect does not significantly modify the relative energy of these conformers. On the other hand, the conformational spaces of the neutral and ionized forms present a great number of equilibrium structures, in a short energetic range (20 Kcal). The results are representative of an exceptional conformational flexibility due to a cooperative effect between several parts of the molecule

Non-tuberculous mycobacteria isolated from slaughter pigs in Mubende district, Uganda

<p>Abstract</p> <p>Background</p> <p>The importance of infections caused by non-tuberculous mycobacteria (NTM) in animals and humans has gained considerable recognition during the past few years. In the developed world, where pig production is extensively practiced, studies on mycobacterial infections and related control strategies have received increasing attention. The infections are reported to be caused by a wide spectrum of NTM. Unfortunately, these infections have been less recognized in sub-Saharan Africa owing to lack of awareness and systematic studies. In this study we aimed at isolating and identifying species of mycobacteria involved in causing infections in slaughter pigs in Mubende district of Uganda. Furthermore we wanted to identify factors associated with infection prevalence in the study area.</p> <p>Methods</p> <p>A total of 363 lymph nodes were collected and cultured for the presence of mycobacteria. Isolates were identified by 16S rDNA gene sequencing. A questionnaire survey was administered to identify production related factors associated with infection prevalence. Data were assembled and analysed using descriptive statistics and mixed effects logistic regression analysis.</p> <p>Results</p> <p>Mycobacteria were detected in 39 % (143/363) of the examined lymph nodes, 63 % (59/93) of lymph nodes with gross lesions typical of mycobacteriosis and 31% (84/270) of lymph nodes with no visible lesions. Nineteen per cent of the isolated mycobacteria were identified as <it>Mycobacterium (M) avium</it>, of these 78% and 22% were <it>M. avium</it> sub sp. <it>Hominissuis</it> and <it>avium</it> respectively. Other mycobacterial species included <it>M. senuense</it> (16%)<it>, M. terrae</it> (7%) and <it>M. asiaticum</it> (6%). This study found free range systems (OR = 3.0; P = 0.034) and use of water from valley dams (OR = 2.0; P = 0.049) as factors associated with high prevalence of mycobacteria in slaughter pigs.</p> <p>Conclusions</p> <p>This study demonstrated a high prevalence of NTM infections among slaughter pigs in Mubende district of Uganda. <it>M. avium</it> was the most prevalent of all NTM isolated and identified. Free range system of pig management and valley dam water were the most significant factors associated with NTM prevalence in Mubende district. These findings could be of a major public health concern given that it is in a predominantly pork consuming population with 18% HIV/AIDS prevalence. Therefore, stringent post-mortem inspection at the slaughter houses is of paramount importance to reduce human exposure.</p

Experimental Challenge of Atlantic Cod (Gadus morhua) with a Brucella pinnipedialis Strain from Hooded Seal (Cystophora cristata)

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Main risk factors associated with small and large ruminant brucellosis

Source at http://epubs.icar.org.in/ejournal/index.php/IJAnS/article/view/118115.Brucellosis is a neglected zoonotic bacterial disease in most of the developing world that has a significant impact on public health. The prevalence of brucellosis in livestock, particularly in large and small ruminants is variable in many countries and seems to remain high, especially amongst subsistence and small-scale livestock farmers. There are different factors that may influence the prevalence of brucellosis in large and small ruminants. This review is aiming at describing the most important factors that need to be taken into consideration for the planning and implementation of effective brucellosis control programmes. Common risk factors in the brucellosis development in small and large ruminant animals include species, age, sex, extensive or intensive production system, herd/flock size, mixed farming, introduction of new animals in the farms, breeding practice, hygiene, absence of vaccination, and awareness of the disease. This review suggests that different risk factors might have various impact on brucellosis seroprevalence that need to be addressed in epidemiological studies in different farming systems

The sero-prevalence of brucellosis in cattle and their herders in Bahr el Ghazal region, South Sudan

<div><p>Background</p><p>Brucellosis is a worldwide recognized bacterial zoonotic disease. There is currently no information on bovine brucellosis sero-prevalence in South Sudan regardless of the economic, social and public health impact on populations. Therefore, for the first time in 33 years, we report the sero-prevalence of brucellosis in cattle and their herders. Furthermore, we characterize the drivers associated with the disease at the human-animal interface in Bahr el Ghazal region, South Sudan.</p><p>Methods</p><p>A total of 893 and 87 animal and human sera respectively were examined between December 2015 and May 2016. Rose Bengal Plate Test (RBPT) and Competitive Enzyme Linked Immuno Sorbent Assay (c-ELISA) were used in parallel to detect anti-<i>Brucella</i> antibodies. Questionnaires were administered to collect relevant metadata used for the association analysis in R version 3.2.3. Odds Ratio (OR) and Confidence Intervals (CI) were determined.</p><p>Results</p><p>Overall bovine brucellosis prevalence was 31% (95%CI = 28.0–34.2), with the highest 63% (95%CI = 53–70) and lowest 10% (95%CI = 4.5–20.1) prevalence estimates in Wau and Gogrial states respectively. The bovine sero-prevalence was approximately equally distributed among the male 30.4% (26.9–34.2) and the females 32.5% (26.8–38.7). Poor body condition (OR = 0.22; 95%CI = 0.07–0.54) and larger herd sizes (OR = 0.05; 95%CI = 0.008–0.173) were protective factors for brucellosis, while the opposite was true for the second (OR = 1.70; 95%CI = 1.08–2.67) and third (OR = 2.5; 95%CI = 1.46–4.47) lactation stage. The overall brucellosis sero-prevalence in herders was estimated at 33.3% (23.9–44.3).</p><p>Conclusion</p><p>We report a high prevalence of anti-<i>Brucella</i> antibodies in cattle and their herders in Bahr el Ghazal, indicating an enzootic status in the cattle population being an important source of infection for humans. This represents a genuine public health challenge. Therefore, there is need to raise awareness and build capacity and infrastructure in this fragile state to underwrite future public health strategies for brucellosis.</p></div

A review of Brucella infection in marine mammals, with special emphasis on Brucella pinnipedialis in the hooded seal (Cystophora cristata)

Brucella spp. were isolated from marine mammals for the first time in 1994. Two novel species were later included in the genus; Brucella ceti and Brucella pinnipedialis, with cetaceans and seals as their preferred hosts, respectively. Brucella spp. have since been isolated from a variety of marine mammals. Pathological changes, including lesions of the reproductive organs and associated abortions, have only been registered in cetaceans. The zoonotic potential differs among the marine mammal Brucella strains. Many techniques, both classical typing and molecular microbiology, have been utilised for characterisation of the marine mammal Brucella spp. and the change from the band-based approaches to the sequence-based approaches has greatly increased our knowledge about these strains. Several clusters have been identified within the B. ceti and B. pinnipedialis species, and multiple studies have shown that the hooded seal isolates differ from other pinniped isolates. We describe how different molecular methods have contributed to species identification and differentiation of B. ceti and B. pinnipedialis, with special emphasis on the hooded seal isolates. We further discuss the potential role of B. pinnipedialis for the declining Northwest Atlantic hooded seal population

Brucella pinnipedialis in hooded seal (Cystophora cristata) primary epithelial cells

License:Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/)Background: Marine Brucella spp. have been isolated from numerous pinniped and cetacean species, but pathological findings in association with infection with Brucella pinnipedialis in pinnipeds have been sparse. The capacity of brucellae to survive and replicate within host macrophages underlies their important ability to produce chronic infections, but previous work has shown that B. pinnipedialis spp. are rapidly eliminated from hooded seal (Cystophora cristata) alveolar macrophages. Results: To investigate if multiplication could take place in other hooded seal cell types, primary epithelial cells were isolated, verified to express the epithelial marker cytokeratin and challenged with three different strains of B. pinnipedialis; B. pinnipedialis sp. nov., B. pinnipedialis hooded seal strain B17, and B. pinnipedialis hooded seal strain 22F1. All strains were steadily eliminated and the amounts of intracellular bacteria were reduced to less than one-third by 48 h post infection. Intracellular presence was verified using immunocytochemistry. Conclusions: So far, intracellular multiplication in seal cells has not been documented for B. pinnipedialis. The lack of intracellular survival in macrophages, as well as in epithelial cells, together with the fact that pathological changes due to B. pinnipedialis infection is not yet identified in seals, suggests that the bacteria may only cause a mild, acute and transient infection. These findings also contribute to substantiate the hypothesis that seals may not be the primary host of B. pinnipedialis and that the transmission to seals are caused by other species in the marine environment

The global epidemiology of Brucella infections in terrestrial wildlife: A meta-analysis

Brucellosis is a widespread zoonotic disease with serious consequences on human and animal health. Brucella infections were reported in many terrestrial wild animals, from subtropical and temperate regions to arctic regions. In many areas, the epidemiology of brucellosis in wildlife is closely associated with the occurrence of the disease in livestock. Some wild species may contribute to the re-introduction of Brucella infections in livestock (spillback), even in officially brucellosis-free (OBF) regions. Through meta-regression analysis, this study draws a global picture of the prevalence of Brucella spp. in terrestrial wild animals, trying to determine most affected subgroups as well as preferential sampling and screening methods. For this purpose, a literature search was carried out among publications published from 1983 to 2019. Different subgroups were compared according to animal species, feeding, gender, age as well as the method used for sampling and for brucellosis diagnostic. To determine heterogeneity of studies, chi-squared test was used and a random-effects model (REM) estimated the pooled prevalence among subgroups. A total of 68 publications, comprising 229 data reports/studies, were selected. The most-reported Brucella species in wildlife was Brucella abortus, and the highest prevalence rate was found in American bison, Bison bison (39.9%) followed by Alpine ibex, Capra ibex (33%). Serology was the most widely applied diagnostic approach (66%), while PCR appeared to be highly sensitive (36.62% of positive results). The gender of animals showed no significant association with the prevalence of brucellosis (p > .05). Blood samples and visceral organs constituted the great majority of specimen used for the detection of Brucella spp., while lymph nodes showed a high prevalence of positive samples (94.6%). The present study provides insight into the global epidemiology and enzootic potential of brucellosis in wild terrestrial animals worldwide, aiming at helping the appropriate authorities to strengthen prevention, surveillance and control strategies