Sérgio Santos de Azevedo

Soroprevalência e fatores de risco para a leptospirose em cães de Campina Grande, Paraíba

The prevalence of leptospirosis was investigated in dogs from Campina Grande city, State of Paraiba, Brazil, and the risk factors for infection were analyzed. Two hundred and eighty five blood samples were collected from dogs during the rabies vaccination campaign, in September 2003. The diagnostic method run for leptospirosis was the microscopic agglutination test, using a batch of 22 leptospiral serovars. The most prevalent serovar was found crossing the results of frequency and titer of agglutinins. The prevalence was 21.4% (95% CI = 16.8%-26.6%) and most frequent reactant serovars were autumnalis (7.4%), copenhageni (6%) and canicola (2.1%). The multivariate logistic regression analysis showed that the risk factors for leptospirosis were: age older than one year (odds ratio = 3.00; P = 0.006), mixed breed (odds ratio = 4.02; P = 0.011) and occurrence of floods in the area (odds ratio = 2.32; P = 0.039).

Soroprevalência de leptospirose em cães errantes da cidade de Patos, Estado da Paraíba, Brasil

This work aimed to survey the prevalence of leptospirosis in stray dogs from Patos city, state of Paraiba, Brazil. This study was held during the period of February to April of 2003, when 130 serum samples were collected. The diagnostic method run for leptospirosis was the microscopic agglutination test, using a batch of 22 leptospiral serovars. The most prevalent serovars were found crossing the results of frequency and titer of agglutinins. The results obtained indicated a prevalence of 20% and most frequent reactant serovars were autumnalis (20%), pomona (17,5%), grippotyphosa (10%) e patoc (10%).

Inquérito sorológico e fatores de risco para a brucelose por Brucella canis em cães do município de Santana de Parnaíba, Estado de São Paulo

The prevalence of brucellosis due to Brucella canis was investigated in dogs of the Santana de Parnaiba county, State of Sao Paulo, southeastern Brazil, and the risk factors for infection were analyzed. For this purpose, 410 blood samples were collected from dogs during the rabies vaccination campaign, in August 1999. The agar gel immunodiffusion test (AGID), using lipopolysaccharides and protein antigens from Brucella ovis, strain Reo 198, was applied first as a screening test on normal sera, and secondly, for confirmation. The same AGID test was applied to sera treated previously with 2-mercaptoethanol (ME-AGID). The complement fixation test (CFT), using B. ovis antigen, strain 63/290, was applied also as a confirmatory test. For the prevalence analysis, animals presenting positive results in both ME-AGID and CFT were considered positive. The prevalence of brucellosis due to B. canis was 2.2% (95% C.I.=1.01-4.13%). Dogs that were allowed by their owners to stay free outside their home had a higher risk for contracting B. canis infection, with an odds ratio value of 8.73 (95% C.I.=1.48-51.55) and p=0.04.

Influência da via de inoculação sobre o estabelecimento e a evolução da leptospirose em hamsters (Mesocricetus auratus) experimentalmente infectados com Leptospira interrogans sorovar pomona

Foi investigada a influencia da via de inoculacao sobre o estabelecimento e a evolucao da leptospirose em hamsters (Mesocricetus auratus) experimentalmente infectados com Leptospira interrogans sorovar pomona. As vias de inoculacao ensaiadas foram: intraperitoneal, subcutânea, oral, conjuntival e escarificacao cutânea. O inoculo infeccioso foi constituido por uma cultura em meio de Fletcher, com 20 a 30 leptospiras por campo microscopio no aumento de 200 vezes. Os animais controle foram inoculados apenas com meio de Fletcher. Foram colhidas amostras de soro sanguineo e fragmentos de rins na fase agonica da doenca ou no 21o dia pos-infeccao, quando todos os animais foram sacrificados. Para a pesquisa de leptospiras, foi feito o exame direto com microscopia optica em campo escuro e cultivo em meio de Fletcher, pela tecnica das diluicoes seriadas. A deteccao de aglutininas anti-leptospiras foi realizada pela tecnica de soroaglutinacao microscopica. A instalacao e evolucao da leptospirose foram afetadas pela via de inoculacao. A via oral foi a menos efetiva em estabelecer a infeccao. Nao foi observada associacao estatistica entre a frequencia de portadores e a via de inoculacao.

Comparação de três testes sorológicos aplicados ao diagnóstico da infecção de caninos por Brucella canis

The agar gel immunodiffusion test (AGID), agar gel immunodiffusion test in sera treated by 2-mercaptoethanol (ME-AGID) and complement fixation test (CFT), applied to diagnosis of the canine brucellosis due to Brucella canis, were compared. For this purposes, 80 blood samples from dogs were collected during the rabies vaccination campaign of Santana de Parnaiba municipality, State of Sao Paulo, in August 1999. The antigens used in the AGID and ME-AGID tests were lipopolysaccharides and proteins from Brucella ovis, strain Reo 198, and in the CFT, the antigen employed was Brucella ovis, strain 63/290. The serological tests were compared two by two by Mc Nemar test, and the agreement was analyzed by the Kappa indicator. The agreement between the CFT and ME-AGID was moderate (Kappa = 0.54), between the AGID and CFT was fair (Kappa = 0.36) and between the AGID and ME-AGID was fair (Kappa = 0.39).

Avaliação de um MPB70-ELISA para diferenciar entre suínos sensibilizados com Mycobacterium bovis ou M. avium

Swine are susceptible to different mycobacteria species, being Mycobacterium bovis an agent of tuberculosis, with most significant zoonotic risks, while M. avium determines a granulomatous lymphadenitis with low zoonotic risk. Currently performed intradermal tests present some important limitations, such as the lack of ability to detect anergic animals or to differentiate among mycobacterial species. In order to improve the TB diagnosis, serological assays have been developed, with encouraging results. The purpose of this study was to evaluate the performance of a MPB70-ELISA in 82 piglets divided into four groups: sensitized by inactivated M. bovis, M. avium, inoculated with oil adjuvant, or with saline solution. The test was able to discriminate between an animal sensitized by M. bovis and animals of the three other groups, including M. avium-sensitized animals; for this reason, we suggest that MPB70-ELISA could be used as a complementary tool for discriminating the agent of the mycobacteriosis, and therefore to diagnose tuberculosis in a swine herd.