[Natural infection by Yersinia pestis, in fleas from plague foci in the northeast of Brazil]. / Pesquisa da infecção natural por Yersinia pestis, em pulicídeos provenientes de focos pestosos do Nordeste do Brasil.

Three different containment transport processes of fleas were evaluated as an approach to the bacteriologic isolation of Yersinia pestis. The three methods employed were: live fleas in glass tubes containing pieces of wrapped filter paper; dead fleas in saline solution; and macerated fleas in Cary-Blair culture medium. The two latter methods were almost equal and superior to the first method. A total of 29512 flea pools, from plaque foci in Northeast Brazil collected during 1966 to 1982 were evaluated by the three methods. Among these samples, 236 (0.80%) flea pools were positive with regard to bacteriological cultivation and/or infection of susceptible animals.

[Bacteriologic and serologic studies of an outbreak of plague in the State of Paraíba, Brazil]. / Estudos bacteriológicos e sorológicos de um surto de peste no Estado da Paraíba, Brasil.

During a plaque outbreak in the Borborema Plateau focus (Paraiba), bacteriological and serological studies were carried out in material from 452 patients (48 positives), 1,938 rodents and other small mammals (75 positives), 4,756 dogs (141 positives) and 2,047 cats (57 positives) obtained from 41 counties (out of which, 21 produced positive samples). Twenty Yersinia pestis strains isolated from material from 3 patients and 17 rodents, displayed biochemical reactions, virulence factors, antibiotic susceptibility and animal experimental pathogenicity similar to those observed in strains previously isolated. According to our findings this recent plague outbreak did not exhibit different factors from those observed during prior outbreaks in other plague foci in the northeast of Brazil.

[The rodent. Akodon arviculoides, Wagner, 1842 (Cricetidae)--importance in plague foci in Brazil]. / Estudo do roedor Akodon arviculoides, Wagner, 1842 (Cricetidae)--importância nos focos pestosos do Brasil.

The occurrence of the rodent Akodon arviculoides Wagner, 1842 in the plague focus of the "Agreste" region of the State of Pernambuco and a report on its ability for survival, reproduction and development in captivity, its susceptibility to Yersinia pestis infection and the role of this rodent species in Brazilian plague foci are reported.