A total of 35 samples (1000 ml each) of pasteurized milk and 25 samples (100 g each) of white cheese purchased at supermarkets in Rio de Janeiro were analyzed for the presence of Aeromonas. Strains of Aeromonas were isolated from 28.5% of pasteurized milk and 32% of white cheese samples. Standard Plate counts in the pasteurized milk samples ranged from 7.2 × 10* to 2.5 × 105 CFU/ml. Total and fecal coliform counts in white cheese samples ranged from 1.9 × 10* to 2.4 × 105 most probable number per g and 3.2 × 102 to 1.2 × 105 most probable number per g, respectively. It was possible to identify Aeromonas caviae (58.9%), Aeromonas hydrophila (12.8%), and Aeromonas schubertii (2.5%) among the cultures isolated from pasteurized milk samples. Twenty-five percent of the strains could only be classified as Aeromonas spp. In white cheese samples, unclassified strains were the most frequent isolates (61.5%) followed by A. hydrophila (26.9%), A. caviae (7.6%) and Aeromonas sobria (3.8%). Only strains of A. hydrophila and A. sobria showed high rate of positive results when tested for the production of hemolysin, cytotoxin, and staphylolytic activity. Heat-stable enterotoxin and autoagglutination test did not correlate as virulence factors. The presence of Aeromonas species in refrigerated food samples suggests that this microorganism could be a potential foodborne pathogen, and dairy products may represent an important vehicle of its transmission.

Nosocomial infections are an important cause of morbidity and mortality all over the world. It has been shown that appropriate environmental hygienic and disinfection practices can be very helpful to hospital infection control. The purpose of this study was to evaluate the bactericidal activity of some disinfectants against antibiotic-susceptible and antibiotic-resistant hospital bacterial isolates. The susceptibility of 27 clinical isolates to disinfectants and antibiotics was determined by the Association of Official Analytical Chemist's (AOAC) Use-Dilution method and by the Kirby-Bauer method, respectively. All strains tested were susceptible to sodium hypochlorite, glutaraldehyde and to the association quaternary ammoniumformaldehyde -ethyl alcohol disinfectants. However, the susceptibility of strains to phenol and to one quaternary ammonium compound was variable. Among twenty-one antibiotic-multiresistant strains (methicillin-resistant staphylococci, Enterococcus spp, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, Enterobacter cloacae, Serratia marcescens and Escherichia coli) eleven (52%) and eight (38%) strains were resistant to the quaternary ammonium and phenol compounds, respectively. Among six isolates that demonstrated susceptibility to antibiotics (staphylococci, Enterococcus spp, P. mirabilis, E. cloacae and E. coli) two strains (33%) showed resistance to these disinfectants. The results demonstrated the lack of correlation between antibiotic-susceptibility and susceptibility to disinfectants in hospital strains.

Fresh and salt water samples analyzed in Rio de Janeiro city showed the presence of Plesiomonas shigelloides. Forty-six strains were isolated from both environments. A high incidence of P. shigelloides was achieved in polluted fresh and salt waters as well as in samples from non-polluted streams. P. shigelloides isolates had biochemical characteristics similar to those already described in the literature. None of the isolates analyzed produced enterotoxin in the suckling mouse assay. Hemolytic activity against sheep and human type A erythrocytes was detected in the strains tested. The results of the antibiotic susceptibility tests indicated that all the isolates were susceptible to the cephalosporins, penicillins combined with a beta-lactamase inhibitor, aminoglycosides, imipenem, norfloxacin, tetracycline, chloramphenicol and trimethoprim-sulfamethoxazole. All the isolates were resistant to the penicillins.

Preliminary studies on pathologic conditions in the testis, epididymis, and the accessory sex glands of cattle have demonstrated that vesiculitis is the most common inflammatory condition in the genitals of Danish bulls. 5 Occasionally, this condition has an acute onset that produces clinical signs and then becomes a chronic disease. 18 Four-polled Hereford bulls approximatedly 1 year of age (1-2 years old) from a farm in southern Brazil were examined by rectal palpation. During this procedure, enlargement of the seminal vesicles was detected. The animals were slaughtered, and samples were collected for bacteriologic and histopathologic examination. Macroscopically, the seminal vesicles were enlarged and firm and contained foci of yellow exudate. The histopathologic examination revealed interstitial seminal vesiculitis with areas of lymphocytic and plasma cell infiltration surrounding alveoli containing suppurative exudate. Varying degrees of fibrosis were found in the glands. Samples of a selected group of organs were available for sectioning.For bacteriologic examination, fragments of seminal vesicles were inoculated asseptically onto 5% (w/v) sheep blood agar and incubated aerobically at 37 C for 24-48 hours. Microorganisms from all seminal vesicles were isolated in pure culture. The colonies were beta-hemolytic, smooth, small, and white and had characteristics of the genus Aeromonas (gram-negative rods, oxidase positive, fermentative metabolism,

Clinical and environmental isolates ofAeromonas species (five A. hydrophila isolates, three A. caviae isolates, and two A. sobria isolates) were tested for their adherence to HEp-2 cells. Clinical isolates ofA. hydrophila and A. sobria exhibited aggregative adherence similar to that presented by enteroadherent-aggregative Escherichia coli. Bacterial aggregates adhered to cells with a typical "stacked-brick" appearance. In contrast, A. caviae strains showed a diffuse adherence pattern.

Thirty-seven (16.9%) of 219 raw milk samples and 38 (13.7%) of 280 pasteurized milk samples were positive for Yersinia sp. The isolates from raw milk samples include Yersinia enterocolitica (32.4%) comprising biotype 1 (0:5, 10.8%), and biotype 2 (0:10 K1, 1.6%); Yersinia intermedia (64.9%) comprising 0:18 (40.5%), 0:7,8 (8.1%), 0:16 (2,7%) and non-typable (13.5%) and Yersinia frederiksenii (0:22, 2.7%). The isolates from pasteurized milk samples include Y. enterocolitica (41.5%) comprising 0:5 (31.7%), 0:13 (2.4%), 0:7,8 (2.4%) and 0:16 (4.8%); Y. frederiksenii (56.1%) comprising 0:27 (7.3%), 0:25,35 (12.2%), non-typable (36.6%) and Y. intermedia (non-typable, 2.4%). Most Y. enterocolitica and about one third of non-Y. enterocolitica strains produce heat-stable toxin (ST). Antibiotic susceptibility, autoagglutination capacity and calcium-dependency of strains also were investigated.

Fresh and salt water samples collected in Rio de Janeiro city were analysed for the presence of motile Aeromonas species. Twenty-six out of 50 aliquots analysed (52%) were positive for Aeromonas. One hundred strains were isolated from both environments (A. caviae, 60%; A. veronii, 14%; A. hydrophila, 1%; A. sobria, 1%; and Aeromonas sp., 24%). Minimal tests such as oxidase, motility, sensitivity to the vibriostatic agent 2,4-diamino-6,7 - diisopropylpteridine, fermentation and gas from glucose, acetoin from glucose (Voges-Proskauer), lysine decarboxylase, ornithine decarboxylase, and esculin hydrolysis were sufficient to classify the majority Aeromonas strains into species. No Aeromonas was found in nonpolluted waters but, in contrast, both fresh and salt polluted waters showed a high incidence of isolates. Most of the Aeromonas strains analysed produced hemolysin and/or heat-stable enterotoxin. The latter was produced by 73% of the A. veronii isolates.

Twenty-five samples of several types of meat purchased at supermarkets in Rio de Janeiro were analyzed for presence of Yersinia. Species were isolated from 80% of beef and chicken giblets, 60% of ground beef and beef liver and 20% of pork, Fifteen strains were identified as Yersinia intermedia, 9 as Yersinia enterocolitica, 4 as Yersinia kristensenii and 1 as Yersinia frederiksenii. Two strains of Y. intermedia, serotype 0:13,7 were positive in both the autoagglutination and calcium-dependency tests. Two strains of atypical Y. intermedia (serotype 0:29 and one not typable) and one strain of atypical Y. enterocolitica, serotype 0:16; were positive only in the auto-agglutination test. Seventeen strains isolated from meat produced heat stable enterotoxin.