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

An evaluation of Irish cattle herds with inconclusive serological evidence of bovine brucellosis

Since 1998, there has been a steady decline in herd restrictions and de-populations in Ireland due to bovine brucellosis. There is concern that the interpretation of laboratory results may become increasingly problematic, as brucellosis prevalence falls in Ireland. Therefore, the purpose of the current study was to evaluate the infection status of Irish herds and animals with inconclusive serological evidence of bovine brucellosis. During 12 months from September 1, 2004, laboratory and observational epidemiological data were collected from all Irish herds where animal testing identified at least one animal with a complement fixation test (CFT) reading greater than zero and/or a positive result to the indirect enzyme-linked immunosorbent assay (iELISA). Due to the observational nature of the study, we have robust estimates of the relative, but not the absolute, performance of the CFT, iELISA and brucellin skin test (BST). Herds were divided into three categories (Group A, B or C) on the basis of test results at initial assessment. A total of 639 herds were enrolled into the study, and observed for at least two years following enrolment. A rising CFT titre, with a CFT reading of 111 International CFT Units (IU) or greater at the subsequent blood test, was generally associated with herds where other evidence of infection was also available. Knowledge of the CFT reading at the initial and a subsequent blood test proved useful in distinguishing false-positive and true-positive brucellosis results. There was poor correlation between the CFT and iELISA results, and between the CFT and BST results. As a result of this study, national policy has been modified to include re-sampling of all animals with CFT readings of 20 IU or greater. This project has also led to a reduction in the number of herds restricted, as well as restriction duration. It has also contributed to a reduction in the number of herds listed for contiguous tests, and therefore the potential for contiguity testing of false positive results

Analyse du risque posé en santé animale par la présence de l'hydroxyméthylfurfural dans les sirops de nourrissement des abeilles domestiques

This paper discusses an incident that occurred in Belgium during winter 2009-2010, after which many honey bee colonies have been lost. Later analyses showed that these colonies had been fed during the winter with a inverted sugar syrup from sugar beet which had a high concentration of hydroxymethylfurfural (HMF). HMF concentrations ranged from 18.8 ppm to 365.6 ppm. Data from the scientific literature are quite limited, but several authors confirm the harmful effect of HMF on honey bee health. Other elements, however, may have played a role in this apparent mortality such as crystallization of syrups, resulting in unavailability of sugar for the honey bees, and thus the death of them from starvation. Pending the acquisition of new scientific knowledge on the subject, it is recommended to follow good beekeeping practices detailed in this article to minimize the formation of HMF in syrups for honey bee feeding. In addition, a draft action limit corresponding to a maximal concentration of 40 ppm of HMF is proposed in order to control the risk at the producer and distributor of syrups for honey bee feeding level

Bayesian evaluation of three serological tests for the diagnosis of bovine brucellosis in Bangladesh

We evaluated the performance of three serological tests – an immunoglobulin G indirect enzyme linked immunosorbent assay (iELISA), a Rose Bengal test and a slow agglutination test (SAT) – for the diagnosis of bovine brucellosis in Bangladesh. Cattle sera (n = 1360) sourced from Mymensingh district (MD) and a Government owned dairy farm (GF) were tested in parallel. We used a Bayesian latent class model that adjusted for the conditional dependence among the three tests and assumed constant diagnostic accuracy of the three tests in both populations. The sensitivity and specificity of the three tests varied from 84.6% to 93.7%, respectively. The true prevalences of bovine brucellosis in MD and the GF were 0.6% and 20.4%, respectively. Parallel interpretation of iELISA and SAT yielded the highest negative predictive values: 99.9% in MD and 99.6% in the GF; whereas serial interpretation of both iELISA and SAT produced the highest positive predictive value (PPV): 99.9% in the GF and also high PPV (98.9%) in MD. We recommend the use of both iELISA and SAT together and serial interpretation for culling and parallel interpretation for import decisions. Removal of brucellosis positive cattle will contribute to the control of brucellosis as a public health risk in Bangladesh

Preliminary surveys fail to detect batrachochytrium dendrobatidis infection in the United Arab Emirates and Oman

Chaber, Anne-Lise, Combreau, Olivier, Perkins, Matthew, Saegerman, Claude, Cunningham, Andre

Preliminary surveys fail to detect batrachochytrium dendrobatidis infection in the United Arab Emirates and Oman

Chaber, Anne-Lise, Combreau, Olivier, Perkins, Matthew, Saegerman, Claude, Cunningham, Andre