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Control of bovine tuberculosis (TB) in cattle has proven particularly challenging where reservoirs of infection exist in wildlife populations. In Britain and Ireland, control is hampered by a reservoir of infection in Eurasian badgers (Meles meles). Badger culling has positive and negative effects on bovine TB in cattle and is difficult, costly and controversial. Here we show that Bacillus Calmette-Guérin (BCG) vaccination of captive badgers reduced the progression, severity and excretion of Mycobacterium bovis infection after experimental challenge. In a clinical field study, BCG vaccination of free-living badgers reduced the incidence of positive serological test results by 73.8 per cent. In common with other species, BCG did not appear to prevent infection of badgers subjected to experimental challenge, but did significantly reduce the overall disease burden. BCG vaccination of badgers could comprise an important component of a comprehensive programme of measures to control bovine TB in cattle.

Quadruple vaccine containing 75 D antigen units of killed type 1 poliovirus was given to children at ages 2, 3 and 4 months followed by a booster dose at 15 months.The serological response to the primary course was difficult to assess owing to maternal antibody. Antibody titres to the type 1 component after the booster dose were very satisfactory and about 10 times higher than those observed in a similar group of children given attenuated vaccine. Response to the poliovirus types 2 and 3 in the quadruple vaccine was less satisfactory.Graded doses of attenuated poliovirus type 1 were fed to the children 2 months after the primary course and 1 month after the booster dose. Children who had received no poliovaccine and children immunized with attenuated vaccine were included for comparison.Immunization with killed vaccine did not greatly affect the size of the minimal infecting dose of live virus but reduced both the duration of the subsequent infection and the titre of virus in the faeces.The epidemiological significance of these findings is discussed.

We describe epidemiological trends in Mycobacterium bovis infection in an undisturbed wild badger (Meles meles) population. Data were derived from the capture, clinical sampling and serological testing of 1803 badgers over 9945 capture events spanning 24 years. Incidence and prevalence increased over time, exhibiting no simple relationship with host density. Potential explanations are presented for a marked increase in the frequency of positive serological test results. Transmission rates (R0) estimated from empirical data were consistent with modelled estimates and robust to changes in test sensitivity and the spatial extent of the population at risk. The risk of a positive culture or serological test result increased with badger age, and varied seasonally. Evidence consistent with progressive disease was found in cubs. This study demonstrates the value of long-term data and the repeated application of imperfect diagnostic tests as indices of infection to reveal epidemiological trends in M. bovis infection in badgers.

BackgroundAccurate diagnosis of tuberculosis (TB) due to infection with Mycobacterium bovis is notoriously difficult in live animals, yet important if we are to understand the epidemiology of TB and devise effective strategies to limit its spread. Currently available tests for diagnosing TB in live Eurasian badgers (Meles meles) remain unvalidated against a reliable gold standard. The aim of the present study was to evaluate the diagnostic accuracy and optimal use of three tests for TB in badgers in the absence of a gold standard.Methodology/Principal FindingsA Bayesian approach was used to evaluate the diagnostic accuracy and optimal use of mycobacterial culture, gamma-interferon assay and a commercially available serological test using multiple samples collected from 305 live wild badgers. Although no single test was judged to be sufficiently sensitive and specific to be used as a sole diagnostic method, selective combined use of the three tests allowed guidelines to be formulated that allow a diagnosis to be made for individual animals with an estimated overall accuracy of 93% (range: 75% to 97%). Employing this approach in the study population of badgers resulted in approximately 13 out of 14 animals having their true infection status correctly classified from samples collected on a single capture.Conclusions/SignificanceThis method of interpretation represents a marked improvement on the current procedure for diagnosing M. bovis infection in live badgers. The results should be of use to inform future test and intervention strategies with the aim of reducing the incidence of TB in free-living wild badger populations.

Impetigo contagiosa may be defined as an acute, superficial infection of the skin characterized by exudation and crusting. In this country it is at present mainly seen in children, although it has been an important cause of minor illness among troops in wartime. It appears to have become much less common in the last 10 years, though a recent increase in incidence has been reported (Sneddon, 1953). In the 90 years since the original clinical description of Fox (1864) there appear to have been repeated fluctuations in the prevalence of the disease, and also differences in frequency, severity and predominant clinical type in different parts of the world. It is not surprising, therefore, that there have been great discrepancies between the bacteriological findings of various workers, and that the controversy between the supporters of the staphylococcal and the streptococcal theories of the aetiology of the diseasehas continued for almost 60 years. Most dermatologists nowrecognize the existence of at least two clinical types of impetigo, associated respectively with haemolytic streptococci and with Staphylococcus aureus, though it is not always possible to make such a clinical distinction in the individual case (Epstein, 1940).The investigation reported here falls into two parts, the first of which was carried out in association with Dr L. C. Martin in Cambridge in the years 1941-2 and was concerned with impetigo in young adult service men. The second was occasioned by an increased prevalence of impetigo in the City of Salford in 1953(Burn, 1954, particularly during the last few months of the year. There was an unusually high proportion of severe cases, many of which were of the bullous type.The Cambridge investigation showed that a large proportion of Staph. aureus strains from impetigo cases (and a much smaller proportion from other sources) had the ability to inhibit corynebacteria. The Manchester investigation showed that most of the impetigo staphylococci belonged to a single unusual phage type, members of which were usually able to inhibit corynebacteria and were penicillinresistant, and that the haemolytic streptococci were largely confined to two particular serological types.

BackgroundStoat (Mustela erminea) and weasel (Mustela nivalis) populations in south-west England are declining whilst polecats (Mustela putorius), absent for over a century, are increasing. Little is known about the health status of these species nationally. This study aimed at investigating respiratory disease in specimens found dead in south-west England.ResultsTrauma caused by road traffic, predator attack or being trapped was the predominant cause of death in 42 stoats, 31 weasels and 20 polecats; most were in good physical condition. Skrjabingylus nasicola was present in all species (weasels 37 %, polecats 39 %, stoats 41 %) and infected animals showed no evidence of loss of body condition. Even in carcases stored frozen L1 larvae were frequently alive and highly motile. Angiostrongylus vasorum infection was diagnosed in two stoats and one weasel: in stoats infections were patent and the lung lesions were likely of clinical significance. These are believed to be the first records of A. vasorum in small mustelids. Pleuritis and pyothorax was seen in two polecats, in one case due to a migrating grass awn. Histological examination of lungs showed granulomata in stoats (38 %), weasels (52 %) and polecats (50 %). Spherules consistent with Emmonsia spp. adiaspores were present in the granulomata of stoats (60 %), weasels (36 %) and polecats (29 %). Adiaspore diameter in all three species was similar (means: stoats 39 μm, weasels 30 μm, polecats 36 μm); these are markedly smaller than that normally recorded for E. crescens. Although they lie within the accepted range for spores of Emmonsia parva this arid-zone species is not found in Britain, thus raising a question over the identity of the fungus. Cases showing numerous granulomata but few or no adiaspores were Ziehl-Neelsen-stain negative for acid-fast bacilli and IHC negative for Mycobacterium spp. However, in some cases PCR analyses revealed mycobacteria, including Mycobacterium kumamotonense and Mycobacterium avium Complex. One stoat had numerous unidentified small organisms present centrally within granulomata.ConclusionsStoats, weasels and polecats in south-west England share several respiratory diseases, often of high prevalence, but the pathology would appear insufficient to impact on the health status of the populations and other ultimate causes of death should be investigated when examining these species.

SummaryHeterogeneity in the progression of disease amongst individual wild animals may impact on both pathogen and host dynamics at the population level, through differential effects on transmission, mortality and reproductive output. The role of the European badger (Meles meles) as a reservoir host for Mycobacterium bovis infection in the UK and Ireland has been the focus of intense research for many years. Here, we investigate life-history correlates of infection in a high-density undisturbed badger population naturally infected with M. bovis. We found no evidence of a significant impact of M. bovis infection on female reproductive activity or success, with evidence of reproduction continuing successfully for several years in the face of M. bovis excretion. We also found evidence to support the hypothesis that female badgers are more resilient to established M. bovis infection than male badgers, with longer survival times following the detection of bacterial excretion. We discuss the importance of infectious breeding females in the persistence of M. bovis in badger populations, and how our findings in male badgers are consistent with testosterone-induced immunosuppression. In addition, we found significant weight loss in badgers with evidence of disseminated infection, based on the culture of M. bovis from body systems other than the respiratory tract. For females, there was a gradual loss of weight as infection progressed, whereas males only experienced substantial weight loss when infection had progressed to the point of dissemination. We discuss how these differences may be explained in terms of resource allocation and physiological trade-offs.