Advances in understanding disease epidemiology and implications for control and eradication of tuberculosis in livestock: the experience from New Zealand

A deteriorating tuberculosis problem in cattle and deer in New Zealand has been halted and then reversed over the last decade. Mycobacterium bovis infection in both wild and domestic animal populations has been controlled. This has been achieved by applying a multi-faceted science-based programme. Key features of this have been a comprehensive understanding of the epidemiology of tuberculosis in animals, confidence in sampling wild animal populations, effective application of diagnostic tests in cattle and deer, and the ability to map M. bovis genotypes.

[Animal pathogens as biological weapons]

In this article, the most important animal pathogens, which, according to CDC classification, can be used as biological agents, are presented. The means of dissemination and the ways of infection's propagation are reviewed. Typical and the most dangerous signs and symptoms are described, as well as the consequences of these infections.

Development of a procedure for discriminating among Escherichia coli isolates from animal and human sources

Counts of Escherichia coli cells in water indicate the potential presence of pathogenic microbes of intestinal origin but give no indication of the sources of the microbial pollution. The objective of this research was to evaluate methods for differentiating E. coli isolates of livestock, wildlife, or human origin that might be used to predict the sources of fecal pollution of water. A collection of 319 E. coli isolates from the feces of cattle, poultry, swine, deer, goose, and moose, as well as from human sewage, and clinical samples was used to evaluate three methods. One method was the multiple-antibiotic-resistance (MAR) profile using 14 antibiotics. Discriminant analysis revealed that 46% of the livestock isolates, 95% of the wildlife isolates, and 55% of the human isolates were assigned to the correct source groups by the MAR method. Amplified fragment length polymorphism (AFLP) analysis, the second test, was applied to 105 of the E. coli isolates. The AFLP results showed that 94% of the livestock isolates, 97% of the wildlife isolates, and 97% of the human isolates were correctly classified. The third method was analysis of the sequences of the 16S rRNA genes of the E. coli isolates. Discriminant analysis of 105 E. coli isolates indicated that 78% of the livestock isolates, 74% of the wildlife isolates, and 80% of the human isolates could be correctly classified into their host groups by this method. The results indicate that AFLP analysis was the most effective of the three methods that were evaluated.

O-antigen structural variation: mechanisms and possible roles in animal/plant-microbe interactions

Current data from bacterial pathogens of animals and from bacterial symbionts of plants support some of the more general proposed functions for lipopolysaccharides (LPS) and underline the importance of LPS structural versatility and adaptability. Most of the structural heterogeneity of LPS molecules is found in the O-antigen polysaccharide. In this review, the role and mechanisms of this striking flexibility in molecular structure of the O-antigen in bacterial pathogens and symbionts are illustrated by some recent findings. The variation in O-antigen that gives rise to an enormous structural diversity of O-antigens lies in the sugar composition and the linkages between monosaccharides. The chemical composition and structure of the O-antigen is strain-specific (interstrain LPS heterogeneity) but can also vary within one bacterial strain (intrastrain LPS heterogeneity). Both LPS heterogeneities can be achieved through variations at different levels. First of all, O-polysaccharides can be modified non-stoichiometrically with sugar moieties, such as glucosyl and fucosyl residues. The addition of non-carbohydrate substituents, i.e. acetyl or methyl groups, to the O-antigen can also occur with regularity, but in most cases these modifications are again non-stoichiometric. Understanding LPS structural variation in bacterial pathogens is important because several studies have indicated that the composition or size of the O-antigen might be a reliable indicator of virulence potential and that these important features often differ within the same bacterial strain. In general, O-antigen modifications seem to play an important role at several (at least two) stages of the infection process, including the colonization (adherence) step and the ability to bypass or overcome host defense mechanisms. There are many reports of modifications of O-antigen in bacterial pathogens, resulting either from altered gene expression, from lysogenic conversion or from lateral gene transfer followed by recombination. In most cases, the mechanisms underlying these changes have not been resolved. However, in recent studies some progress in understanding has been made. Changes in O-antigen structure mediated by lateral gene transfer, O-antigen conversion and phase variation, including fucosylation, glucosylation, acetylation and changes in O-antigen size, will be discussed. In addition to the observed LPS heterogeneity in bacterial pathogens, the structure of LPS is also altered in bacterial symbionts in response to signals from the plant during symbiosis. It appears to be part of a molecular communication between bacterium and host plant. Experiments ex planta suggest that the bacterium in the rhizosphere prepares its LPS for its roles in symbiosis by refining the LPS structure in response to seed and root compounds and the lower pH at the root surface. Moreover, modifications in LPS induced by conditions associated with infection are another indication that specific structures are important. Also during the differentiation from bacterium to bacteroid, the LPS of Rhizobium undergoes changes in the composition of the O-antigen, presumably in response to the change of environment. Recent findings suggest that, during symbiotic bacteroid development, reduced oxygen tension induces structural modifications in LPS that cause a switch from predominantly hydrophilic to predominantly hydrophobic molecular forms. However, the genetic mechanisms by which the LPS epitope changes are regulated remain unclear. Finally, the possible roles of O-antigen variations in symbiosis will be discussed.

Trends in antimicrobial resistance of Salmonella isolated from animals, foods of animal origin, and the environment of animal production in Canada, 1994-1997

The purpose of our study was to determine the occurrence, magnitude, trends, and relationships regarding antibiotic resistance of Salmonella isolated from animals, animal food products, and the environment of animals. We examined 621 strains of 67 different serovars isolated in 1994, 721 strains of 75 different serovars isolated in 1995, 1,219 strains of 83 different serovars isolated in 1996, and 1,336 Salmonella strains of 92 different serovars isolated in 1997, for resistance to 17 antibiotics at one to three different concentrations with the agar dilution method. The overall resistance magnitude regressed from 9.2% in 1994 to 8.1% in 1997. Resistance to streptomycin (30.4% of 3,897 isolates), tetracycline (27.3%), and sulfisoxazole (23.7%) was highest. Resistance to streptomycin, tetracycline, kanamycin, and gentamicin declined during the 4-year period. Notable increases in resistance to ampicillin, chloramphenicol, and neomycin occurred during the 1994-1997 years. None of the isolates was resistant to amikacin. None of the isolates was resistant to ciprofloxacin at 1, 2, and 4 microg/ml. Salmonella bredeney isolates from turkeys showed a decreased sensitivity to ciprofloxacin and were resistant at the low level of 0.125 microg/ml, but none of these isolates was resistant at 1 microg/ml. Resistance to nalidixic acid correlated significantly with decreased sensitivity to ciprofloxacin; 122 of 127 (96%) isolates resistant to nalidixic acid at 32 microg/ml were resistant to ciprofloxacin at 0.125 microg/ml but sensitive at 1 microg/ml. Resistance to S. typhimurium to each of the seven antibiotics ampicillin, chloramphenicol, kanamycin, neomycin, streptomycin, sulfisoxazole, and tetracycline increased persistently during each of the years 1994-1997, but none of the S. typhimurium isolates showed decreased sensitivity to ciprofloxacin. Clinical isolates of Salmonella were twice as frequently resistant to the antimicrobials in the test panel than isolates obtained during surveys. Salmonella isolates from turkeys were more frequently resistant than isolates from pigs, cattle, and chickens.

Antibiotic resistance in bacteria of animal origin: methods in use to monitor resistance in EU countries

A study on the ongoing monitoring programmes in 13 European countries was made as part of a concerted action funded by the European Commission. Five main reference systems were used in the surveyed countries and three categories of bacteria were monitored, zoonotic agents, indicator bacteria and veterinary pathogens. The five reference systems and an overview of the national monitoring programmes are described. Differences exist and there is a real need for standardisation at the European level. This harmonisation could be set up both for microbiological methods and the epidemiological results derived from common methods. Disk diffusion methods are most widely used and many of the monitored species and control strains are similar in the action's participating countries.

Antibiotic resistance monitoring in bacteria of animal origin: analysis of national monitoring programmes

Methods of antibiotic resistance monitoring of bacteria from animals in 12 European countries were surveyed in 1998. Most laboratories used disk diffusion methods, usually expressing results qualitatively, although a few also expressed the results either as MICs or zone diameters. The number of antibiotics used ranged from 5 to 37 (mean 15) and the most common antibacterials were streptomycin, gentamicin, neomycin, ampicillin, tetracyclines, chloramphenicol and sulphonamides. Salmonellae were monitored by most centres but few-tested campylobacter regularly. Escherichia coli from a wide range of animal species were tested in nine countries. Enterococci were tested on a limited ad hoc basis in six countries. Staphylococci, streptococci and pasteurellae were also frequently monitored but the number of isolates tested showed wide variation. Overall the presentation of the results differed, but most programmes used disk diffusion, control strains and monitored similar bacteria. Thus, it may be possible to harmonise monitoring programmes within the EU.

Bacterial symbioses. Predation and mutually beneficial associations

The endosymbiotic theory, which has proved to explain the origin of mitochondria and chloroplasts, also posits the origin of nucleus and other cellular organelles that could have derived from ancient relationships among bacteria. It seems that predation might have been a prerequisite to the establishment of symbiosis as a source of evolutionary novelty. This review describes current different examples of bacteria able not only to attack and degrade other bacteria, but also to establish stable symbiotic relationships with different eukaryotic organisms.

Functions of bacterial flagella

Many bacterial species are motile by means of flagella. The structure and implantation of flagella seems related to the specific environments the cells live in. In some cases, the bacteria even adapt their flagellation pattern in response to the environmental conditions they encounter. Swarming cell differentiation is a remarkable example of this phenomenon. Flagella seem to have more functions than providing motility alone. For many pathogenic species, studies have been performed on the contribution of flagella to the virulence, but the result is not clear in all cases. Flagella are generally accepted as being important virulence factors, and expression and repression of flagellation and virulence have in several cases been shown to be linked. Providing motility is always an important feature of flagella of pathogenic bacteria, but adhesive and other properties also have been attributed to these flagella. In nonpathogenic bacterial colonization, flagella are important locomotive and adhesive organelles as well. In several cases where competition between several bacterial species exists, motility by means of flagella is shown to provide a specific advantage for a bacterium. This review gives an overview of studies that have been performed on the significance of flagellation in a wide variety of processes where flagellated bacteria are involved.

Safe biotechnology (5). Recommendations for safe work with animal and human cell cultures concerning potential human pathogens

The benefits of using animal or human cell cultures have been clearly demonstrated in diagnostic and therapeutic research and in their application for manufacturing. Cell cultures serve as a tools for the production of vaccines, receptors, enzymes, monoclonal antibodies and recombinant DNA-derived proteins. They represent an integral part of drug development for which corresponding facilities, equipment and manufacturing processes are required. Although the cells themselves offer no particular risk to workers in laboratories and production areas or to the environment, the cell cultures may be contaminated with viruses, mycoplasma, bacteria, yeast and fungi or might contain endogenous viruses. The containment level for animal and human cells is therefore determined by the risk class of these agents. The history of animal and human cell cultures has proved that they can be handled safely. The recommendations in this publication concern the safe handling of cell cultures (tissue explants, primary cell cultures) and permanent cell lines of animal and human origin. A classification system of safety precautions has been elaborated according to the potential for contamination with the pathogenic agents involved.

In vitro susceptibility of bacteria to a ticarcillin-clavulanic acid combination

In vitro testing of bacterial susceptibility to a combination of ticarcillin and clavulanic acid was done, using 406 aerobic gram-positive and gram-negative isolates (considered to be pathogens) cultured from equine and small animal specimens. A microdilution broth technique of susceptibility testing was performed, using trays with wells containing a range of doubling concentrations of dehydrated ticarcillin (range, 0.50 to 128 micrograms/ml) with fixed concentration of clavulanic acid (4 micrograms/ml). The following isolates of equine origin were (90%) susceptible to concentrations of ticarcillin and clavulanic acid combinations of less than or equal to 16 and 4 micrograms/ml, respectively: Staphylococcus aureus, S intermedius, Klebsiella pneumoniae, Enterobacter aerogenes, Ent agglomerans, Ent cloacae, Escherichia coli, Actinobacillus sp, Corynebacterium pseudotuberculosis, Rhodococcus equi, Proteus vulgaris, and Bordetella bronchiseptica. Isolates of small animal origin (90%) susceptible to less than or equal to 16 and 4 micrograms of ticarcillinclavulanic/ml included S aureus, S intermedius, Ent aerogenes, Ent agglomerans, Pasteurella multocida, B bronchiseptica, Pr mirabilis, and Serratia sp.

Tuberculosis in East Sussex. IV. A systematic examination of wild mammals other than badgers for tuberculosis

A detailed investigation of the possible role of wild mammals, other than badgers, in the maintenance of Mycobacterium bovis in an area on the South Downs of East Sussex was carried out over 3 years. Estimates of population sizes were made where possible and minimum sample sizes were selected to be 95% certain of including at least one infected animal if the prevalence was at least 5%. Samples of wild mammals were taken from populations which had the highest potential direct or indirect contact rate with known infected badgers. M. bovis was not isolated from any of the 15 species of wild mammals. It was concluded that badgers are able to maintain M. bovis in an area independently of other species, and that in the area studied other species were not a source of infection for the cattle herds.

Ribavirin therapy for Hantaan virus infection in suckling mice

We recently reported that ribavirin inhibited Hantaan virus (HV) replication in vitro. In the present study, we used the HV suckling mouse model to evaluate the efficacy of treatment with various doses of ribavirin. Beginning on day 10, untreated animals, infected with ten times the amount of HV (strain 76/118) required to kill 50% of the animals, lost weight; by days 15 to 18, they developed paralysis of both hind limbs, and they died between days 20 and 21. Treatment with 50 mg of ribavirin/kg per day begun on day 10-following onset of early clinical signs and demonstrable virus in serum and organs--saved 11 of 20 animals compared with 0 of 70 controls. Treated animals did not develop further signs of infection, and by day 22, survivors resumed normal weight gain. After ribavirin treatment, titers of virus decreased in serum, liver, and spleen by two days; in lung within six days; and in the kidney by eight days. By day 18, titers in organs of treated animals were 100-fold lower than in sham-treated animals, with the exception of the brain. Titers of virus in brain fell by day 20, when virus in untreated animals reached greater than 10(7) pfu/g. Treated survivors continued to have decreasing titers of virus in organs and were followed for 75 days with no sign of disease recurrence.

Evidence for the presence of duck hepatitis B virus in wild migrating ducks

A virus closely related to duck hepatitis B virus (DHBV) was isolated from serum and liver samples of wild migratory ducks (mallards) caught in two separate wildlife reserve parks in France. In the first one (Dombes region) 12% of wild mallards were positive for DHBV, and in the second (River Somme) 3% of mallards were found positive. The DHBV isolated from the serum of wild mallards was also associated with an endogenous DNA polymerase activity capable in vitro of completing a partially double-stranded viral DNA into a fully double-stranded DNA of 3 kb. The various replicative DNA forms reported for DHBV were also detected in the liver of wild viraemic mallards. The DNA restriction enzyme pattern of the wild mallard strain differed from that of American and French strains of DHBV. The wild mallard strain DHBV was experimentally transmitted to mallard and Pekin ducklings and induced a chronic viraemia in both varieties of infected birds. This strain might be the common ancestor of all DHBV strains isolated from domestic ducks world-wide. The discovery of a DHBV-related virus in the natural wild population might be an important clue in the study of the different roles of environmental, host and viral factors in the pathogenesis of DHBV infection, and their possible oncogenic action in ducks.

Q fever pneumonia associated with exposure to wild rabbits

4 patients with atypical pneumonia and a history of exposure to wild rabbits were found to have antibodies to Coxiella burnetii but not to the other organisms also commonly associated with atypical pneumonia. 10 (45%) of 22 snowshoe hares caught in the area where 1 of the patients snared his rabbits had antibodies to Coxiella burnetii. Q fever ought to be included in the differential diagnosis of pneumonia acquired following exposure to wild rabbits.

Influenza virus surveillance in waterfowl in Pennsylvania after the H5N2 avian outbreak

During the latter stages of the lethal H5N2 influenza eradication program in domestic poultry in Pennsylvania in 1983-84, surveillance of waterfowl was done to determine if these birds harbored influenza viruses that might subsequently appear in poultry. From late June to November 1984, 182 hemagglutinating viruses were isolated from 2043 wild birds, primarily ducks, in the same geographical area as the earlier lethal H5N2 avian influenza outbreak. The virus isolates from waterfowl included paramyxoviruses (PMV-1, -4, and -6) and influenza viruses of 13 antigenic combinations. There was only one H5N2 isolate from a duck. Although this virus was antigenically related to the lethal H5N2 virus, genetic and antigenic analysis indicated that it could be discriminated from the virulent family of H5N2 viruses, and it did not originate from chickens. Many of the influenza viruses obtained from wild ducks were capable of replicating in chickens after experimental inoculation but did not cause disease. These studies show that many influenza A virus strains circulating in waterfowl in the vicinity of domestic poultry in Pennsylvania did not originate from domestic poultry. These influenza viruses from wild ducks were capable of infecting poultry; however, transmission of these viruses to poultry apparently was avoided by good husbandry and control measures.

Rotavirus infection in wild marsupials (Didelphis marsupialis) of the Amazon region

Rotavirus was detected by enzyme-linked immunosorbent assay in faecal specimens collected from two (1.35%) of 148 marsupials trapped in the Amazon jungle environment. The positive samples were both from the "common opossum", Didelphis marsupialis. No infections were found in the stools of 198 animals belonging to other mammalian species: the latter included small rodents, chiropterans and primates. Electron microscopic examination of one (MA 5928) rotavirus-positive specimen showed a large number of empty particles. However, both rotavirus strains grew when inoculated in MA 104 cells (foetal Rhesus monkey kidney cells) producing clear cytopathogenic effect; indirect immunofluorescence technique of these cells showed a typical granular cytoplasmic fluorescence. The electrophoretic profile of strain MA 5928 showed a high grade of homology with that of SA 11, but also showed minor differences.

Serotyping of Campylobacter jejuni, Campylobacter coli, and Campylobacter laridis from domestic and wild animals

By using 50 unabsorbed antisera, we were able to serotype 272 (65.7%) of 414 thermotolerant campylobacters from wild and domestic animals, on the basis of heat-stable antigens identified by means of passive hemagglutination. Forty-two serotypes were recognized. The pattern of serotypes detected in the various animal species was compared to human clinical isolates by using the Czekanowski index (proportional similarity index). The highest degree of similarity to the clinical isolates was observed for the poultry isolates, followed by strains from wild birds, flies, and pigs (in order of decreasing similarity). The serotypes recovered most frequently from poultry (LAU 1 and LAU 2) were also most prevalent in Norwegian patients. In contrast, serotype LAU 35/44, the predominant porcine serotype, was never recovered from human clinical specimens. Flies captured in chicken farms and in piggeries harbored serotypes which were also commonly seen in chickens and pigs, respectively. Nine of the strains included in this study could not be ascribed to any defined species. All of these were resistant to nalidixic acid and did not produce H2S.

[Adenovirus inclusions in the ileum in coccidiosis in suckling piglets]

Numerous intranuclear inclusion bodies in enterocytes were detected exclusively in the ileum of two nine-day piglets coming from a litter infected with diarrhea. The inclusion bodies were homogeneous in hematoxylin and eosine (HE), their staining was not clear enough, was amphophilic and they filled nearly the whole nucleus. They were eosinophil less often and had a halo on the periphery. Their staining was clearly orange-red in Feulgen's nuclear reaction after re-staining with G orange and bright green. Intranuclear inclusions were located exclusively on shortened villi and pseudovilli of ileum above the follicles of activated Peyer's patches. The findings of intranuclear inclusions in ileum demonstrate adenovirus enteral infections in suckling piglets.

Coxiella burnetii antibodies in some Nigerian dairy cows and their suckling calves

Dairy cows and their suckling calves kept at institutional and governmental farms under semi-intensive husbandry and dual purpose Fulani nomadic herds with extensive management system around Zaria, Nigeria were screened for antibodies against Coxiella burnetii using the capillary agglutination test (CAT). An antibody prevalence of 59.8% detected among 306 dairy cows under both management systems was significantly (P less than 0.01, X2) higher than was found among their suckling calves where 41.0% of 205 calves tested were seropositive. At institutional herds, 61.4% of 176 dairy cows, 47.3% of 110 suckling calves and 43.2% of 44 milk samples contained antibodies to C. burnetii. However, within Fulani nomadic herds, 57.7% of 130, 33.7% of 95 and 62.5% of 40, dairy cows, suckling calves and milk samples respectively, were positive for C. burnetii antibodies. Antibody titres of seropositive cows were similar for both systems as 82 (62.7%) of 122 tested sera had titres of 1:64 or above. It is concluded that milkborne C. burnetii infections could be a health hazard to consumers of raw or unpasteurized milk in this environment, based on high prevalence rates and titres, as some cows could be shedding the organism. The role of management practice in the transmission of C. burnetii is also discussed.

Ecology and epidemiology of Candida species

Exogenous and endogenous sources of pathogenic Candida species and the likely routes of their intra- and inter-human transmission are reviewed. Study of C. albicans strain types from clinical isolates of the fungus has shown that, for each person who harbours C. albicans, the strain type or types at different anatomical sites and at different times is likely to be the same, although exceptions to this rule are not uncommon. Moreover, the population of strain types associated with infection is statistically the same as that isolated in the absence of infection, which emphasises the importance of host debilitation in the aetiology of Candida infections. There are variations among C. albicans strain types in different geographical areas, and differences in phenotypic properties such as serotype and resistance to 5-fluorocytosine correlate also with other phenotypic properties of the fungi.

Ecological and epidemiological aspects in dermatophytoses

Dermatophytes may be divided into several groups on the basis of sources of infection, host preference, clinical spectrum and geographic distribution. Other epidemiological factors are more directly host-related. This paper emphasizes the role of indirect transmission of infective propagules and the degree of exposure to large inocula in the human and animal environment, as detected by direct sampling methods.

Incidence of paramyxoviruses in free-living birds in 1978-1982

Together 41 paramyxovirus (PMV) strains (25 PMV-1, 10 PMV-4, and 6 PMV-6 serotypes) were isolated from cloacal swabs of 910 free-living birds trapped in West Slovakia from 1978 to 1982. The PMV strains were found in 9, mostly aquatic bird species. Strains belonging to the PMV-1 serotype were isolated yearly, indicating its wide distribution and circulation in nature. The strains of PMV-4 and PMV-6 serotypes found only in 1978-1980, represented the first isolations in Europe. Antigenic analysis by haemagglutination-inhibition (HI), neuraminidase-inhibition (NI), complement-fixation (CF), and gel double diffusion (DD) tests proved the relatedness of the surface antigens of newly isolated PMV strains with those of PMV-4/ Duck Hong Kong D3/75 and PMV-6/Duck/Hong Kong 311/80 strains. One-way reaction between PMV-4 serotype and mumps virus was demonstrated using hyperimmune rat sera. Electron microscopic observation of isolated virus strains revealed structures typical of PMV.

Neutralising antibodies to wildebeest-derived malignant catarrhal fever virus in African wildlife

A total of 2,722 sera collected between 1963 and 1983, from 43 different species of wildlife in 11 African countries was examined for neutralising antibodies against the wildebeest-derived strain of malignant catarrhal fever (MCF) virus. Antibodies were demonstrated in 10 species of Bovidae which included eight species from the sub-family Hippotraginae and one species each from Bovinae and Antilopinae. Neutralising antibodies were also recorded in hippopotamus. It is suggested that the high prevalence of antibodies recorded in sera from waterbuck and reedbuck indicate infection with MCF. However, titres in other species may be due to antigenically related viruses.

Creutzfeldt-Jakob Disease. Possible transmission to humans by consumption of wild animal brains

Although the natural mode of spread of the agent responsible for Creutzfeldt-Jakob disease is unknown, several reports suggest oral transmission through consumption of contaminated food or brain. This report summarizes four cases of Creutzfeldt-Jakob disease in which a history of eating the brains of wild goat or squirrel was obtained. These cases support the hypothesis of possible acquisition of Creutzfeldt-Jakob disease by ingestion of the agent from a presumptive reservoir in the central nervous system of wild animals.

Evidence of exposure of waterfowl and other aquatic birds to the hemagglutinating duck adenovirus identical to EDS-76 virus

Serum and fecal samples from 12 species of aquatic birds were studied for evidence of exposure to a hemagglutinating duck adenovirus (DAV). DAV is serologically indistinguishable from egg-drop syndrome-76 virus. A total of 285 serum samples were tested by the hemagglutination-inhibition (HI) test. Forty-two percent of the birds had HI antibodies, with titers ranging from 8 to 256. Wild ducks showed the highest frequency of antibodies (56%) while in coots and grebes, antibody was less frequent, 33% and 26%, respectively. Attempted virus isolations from 79 fecal samples were unsuccessful. The data support the hypothesis that DAV is indigenous in wild duck populations and suggest that infection and viremia are limited in time and occur at a very early age.

Isolation of Leptospira from wild forest animals in Amazonian Brazil

The role of wild, forest animals as reservoirs of Leptospira was investigated in Pará State, north Brazil. 696 animals were examined by culture of kidney tissue; isolates of serovar ballum were made from the rodent Proechimys sp. and the opossum Didelphis marsupialis; leptospires of the serogroups hebdomadis, grippotyphosa and cynopteri were isolated from the armadillo Dasypus novemcinctus, and as yet untyped leptospires were isolated from Proechimys and the procyonid carnivore Nasua nasua. Antibodies to serovars bataviae, butembo, canicola, castellonis, celledoni, grippotyphosa, panama, icterohaemorrhagiae and wolffi were demonstrated among 222 other animals examined by serological methods.

Mycoplasma gallisepticum infection in wild-type turkeys living in close contact with domestic fowl

Mycoplasma gallisepticum was isolated from 2 wild-type turkeys (Meleagris gallopavo) and 1 domestic turkey living in close contact on a farm in Tehama County, California. Sinusitis was detected in 2 of 14 wild-type turkeys and in 1 of 12 feral broad-breasted bronze turkeys, but in none of several chickens on the premises. The entire mixed flock was captured, sinus aspirates were collected from affected birds, and blood samples were obtained from all birds for serologic testing. Blood samples also were obtained from 10 domestic turkeys on adjacent premises from which breeding stock had been borrowed. The M gallisepticum isolated from sinus aspirates was typed and inoculated into susceptible chickens, resulting in airsacculitis. California wild turkeys with and without histories of exposure to domestic fowl and wild turkeys shipped into California from Texas for release were tested for antibodies to M gallisepticum, using the plate agglutination test. Evidence of M gallisepticum infection was not found in wild turkeys at any location other than the original premises.

[Campylobacter jejuni, Yersinia enterocolitica and Salmonella in game and poultry]

Samples of various sorts of game and poultry (other than chicken), obtained from poulterers, hunters, rearing-farms and slaughterhouses, were surveyed for the presence of Campylobacter jejuni, Yersinia enterocolitica and Salmonella. These pathogens were isolated from hare, wild boars, pheasants, guinea-fowl, turkeys, mallards and domestic ducks. Yersinia enterocolitica and Salmonella were also cultured from wild and domestic rabbits. Moreover, Yersinia enterocolitica was isolated from wood pigeons. The possible origins of contamination of game and poultry with these pathogenic bacteria and the risks of food-borne infection caused by these products are discussed.

Isolation and characterization of avipoxviruses from wild birds in Western Australia

Avipoxviruses were isolated from wart-like lesions in an Australian magpie (Gymnorhina tibicen) and a silvereye (Zosterops lateralis), and the poxvirus aetiology of wart-like lesions in a magpie-lark (Grallina cyanoleuca) was confirmed. The three viruses produced typical pock lesions on the chorioallantoic membrane of embryonated eggs and were able to replicate in trypsin-dispersed chick embryo fibroblast cultures but not confluent monolayer cultures. Pock neutralization and immunodiffusion studies showed that the three wild bird isolates were distinct from fowlpox, although antigenically closer to fowlpox than pigeonpox. The magpie and silvereye isolates were more closely related to each other than to the magpie-lark isolate.

[Small wild mammals and arboviruses in Italy]

In 1980 and 1981, sera of 256 small wild mammals (rodentia, insectivora, carnivora) were collected in Piemonte and Southern Italy. They were then tested for antibody against 12 arboviruses by haemagglutination inhibition and complement fixation tests. In the North of the country, 42.8% of sera were found positive against Tahyna or Sicilian Sandfly fever viruses. In the Southern provinces, 44.3% of sera reacted with Bhanja, West Nile or other flaviviruses, Tahyna, Sicilian Sandfly fever and Arumowot viruses. These results lead to suspect the possible role of some small mammals (muridae, Clethrionomys glareolus, Talpa caeca, Talpa romana) in circulating these arboviruses in Italy.

Serovar identification of leptospires of the Australis serogroup isolated from free-living and domestic species in the United Kingdom

Eighteen isolates from the Australis serogroup from free-living and domestic animals were identified using the cross agglutination absorption test. Serovar muenchen was found only in England and Wales in wood mice, short tailed and bank voles, a grey squirrel and a pig. Serovar bratislava was found in hedgehogs in England, Wales and Northern Ireland and also in a brown rat from Northern Ireland. Serovar bratislava was isolated from sheep in both England and Northern Ireland and from horses in Northern Ireland. The distribution of these serovars in relation to possible maintenance hosts is discussed.

Experimental infection of Columba livia with paramyxovirus Yucaipa

The town pigeons (Columba livia) were inoculated intranasally with a Yucaipa-like virus (PLOC/Senegal/273/77). They were then surveyed for virus production in the cloaca over a 10 day period. The virus could be isolated at two, three and four days after inoculation.