Rodents and other small mammal reservoirs in plague foci in northeastern Brazil

Abstract

Introduction: Plague is an acute, infectious zoonotic disease, primarily of wild rodents and their fleas, that affects humans and other mammals. In Brazil, several plague foci are located in the northeast region. Plague surveillance based on monitoring of rodents was discontinued in 2007, and the current information on rodent populations is unsatisfactory. Our purpose was to update the information on rodents and other small mammals in plague foci in northeastern Brazil.
 Methodology: Nine surveys in the historically most important northeastern plague areas were conducted in 2013-2015.
 Results: In this study, 393 animals (13 rodent and four marsupial species) were entrapped. The plague bacterium Yersinia pestis was not detected in tissue sample cultures from the 225 animals that were analyzed. Eighty sera samples were analyzed for anti-F1 antibodies by hemagglutination (HA) and protein A ELISA tests, and all were negative, except for one marsupial, Monodelphis domestica, which was HA positive.
 Conclusions: Qualitative and quantitative differences in the animal populations were observed in the areas surveyed, and the antibody positive marsupial indicated that plague continues to circulate in the wild.

Spatial and Temporal Distribution of Rodents During Active and Quiescent Periods in the Plague Focus in Exu, Northeastern Brazil

“…Practically since the arrival of the plague in Brazil in 1899, during the third pandemic, a surveillance and control program adjusted to the epidemiological situation, ecological and demographic characteristics and scientific and technological conditions has been carried out [7,10,17]. For several decades, the rodents were trapped for detection of the plague bacillus and/or antiplague antibodies [22][23][24]. The surveys among the rodents were discontinued in 2007 due to new evidences that serological survey of plague antibodies among roaming-dogs is a more efficient and cost effective tool for plague surveillance [17].…”

“…Data on rodent collection was obtained by consulting the original documents available at the Nacional Reference Service of Plague (Serviço de Referencia Nacional de Peste: SRP) from the Institute Aggeu Magalhães (IAM), FIOCRUZ PE located at Recife, PE, Brazil. Animal capture and handling methods were performed as previously described [18][19][20][21][22][23].…”

A new multi-species Protein A-ELISA assay for plague diagnosis in humans and other mammal hosts

“…A distinct cut-off was calculated for each peroxidase conjugate. Since the rodent samples included rather heterogeneous range of wild species [21], we could not test them for IgG-ELISA.…”

“…The copyright holder for this this version posted September 23, 2021. ; https://doi.org/10.1101/2021.09.21.21263536 doi: medRxiv preprint evaluate the agreement between the Protein A and IgG methods in ELISA. All sera were kindly provided by the Brazilian Plague Reference Service (SRP) and originated from the routine surveillance of the Brazilian plague areas including human cases, several rodent species and domestic carnivores (stray dogs) that pray on rodents [21,22].…”

Seroprevalence and spatial distribution dynamics of Yersinia pestis antibodies in dogs and cats from plague foci in the State of Ceará, Northeastern Brazil

“…This could be because many diseased cats do not survive the infection, while dogs are more resistant and more likely to recover 10 . Because it was assumed that plague antibody detection is more sensitive in dogs than in cats and rodents, the plague surveillance of cats was discontinued in the Brazilian foci areas 24 . Despite the low antibody-positive prevalence (< 1%) during the study period (with the exception of 1997 and 2001), cats tested antibody-positive in all years investigated.…”