Mycobacterium leprae Infection in a Wild Nine-Banded Armadillo, Nuevo León, Mexico

Nine-banded armadillos (Dasypus novemcinctus) are naturally infected with Mycobacterium leprae and are implicated in the zoonotic transmission of leprosy in the United States. In Mexico, the existence of such a reservoir remains to be characterized. We describe a wild armadillo infected by M. leprae in the state of Nuevo León, Mexico.

Survey of Leptospira spp. and Brucella abortus in Free-Ranging Armadillos from Pantanal, Brazil

Out of the 20 recognized species of armadillos in the world, 11 are found in Brazil, and five of them are found in Pantanal, one of the world's largest wetlands. Beef cattle (Bos taurus) farming is the main economic activity in this region, which promotes intense wildlife-livestock contact and increases the likelihood of pathogen exposure, including to agents with zoonotic and economic relevance. Previous studies demonstrated that several wildlife species in Pantanal have been exposed to Brucella abortus and Leptospira spp.; however, little is known regarding the exposure and/or prevalence of zoonotic pathogens in armadillos. We used conventional PCR, the rose Bengal test (RBT), and the microscopic agglutination test (MAT) to investigate the exposure to and infection by Brucella spp. and Leptospira spp. using blood samples from four species of armadillos: nine-banded armadillo (Dasypus novemcinctus, n=2), southern naked-tailed armadillo (Cabassous unicinctus, n=8), yellow armadillo (Euphractus sexcinctus, n=16), and giant armadillo (Priodontes maximus, n=22), captured in Nhecolândia, Pantanal, Brazil. Samples were PCR- and RBT-negative for Brucella spp. infection and exposure. However, MAT revealed a Leptospira spp. seroprevalence of 31% (5/16; 95% confidence interval [CI]=0.11-0.58) in yellow armadillo and 18% (4/22; 95% CI=0.05-0.40) in giant armadillo specimens to serogroups Autumnalis, Cynopteri, and Pomona, with titers ranging from 200 to 1,600. Our results contribute to the understanding of zoonotic pathogens in armadillos in Pantanal and reinforce the importance of wildlife health surveillance in this area.

Amblyomma auricularium (Ixodida: Ixodidae) in Florida: New Hosts and Distribution Records

Previous published evidence for the occurrence of an exotic armadillo tick, Amblyomma auricularium (Conil), in Florida is scant, but we found it is fully established and integrated into the state's tick fauna. We collected 11,192 specimens of this tick from naturalized nine-banded armadillos, Dasypus novemcinctus L., and 14 other species of wild native mammals and birds in Florida, while sampling statewide during 2004 through 2007. In all, we document its specific presence only in 14 contiguous South Florida counties. Moreover, we report the first collections of A. auricularium from the Virginia opossum (Didelphis virginiana Kerr), common raccoon [Procyon lotor (L.)], cotton deermouse [Peromyscus gossypinus (Le Conte)], gray fox [Urocyon cinereoargenteus (Schreber)], eastern spotted skunk [Spilogale putorius (L.)], and white-tailed deer [Odocoileus virginianus (Zimmerman)]. For the first time on birds, we report the collection of this tick from the broad-winged hawk [Buteo platypterus (Vieillot)], northern cardinal [Cardinalis cardinalis (L.)], Carolina wren [Thryothorus ludovicianus (Latham)], gray catbird [Dumetella carolinensis (L.)], and yellow-rumped warbler [Setophaga coronata (L.)]. In addition, we report unattached A. auricularium collected from humans for the first time, and additional new collections from domestic dogs, Canis lupus familiaris L.

Zoonotic Leprosy in the Southeastern United States

The geographic range and complexity of this disease are increasing.

Nine-banded armadillos (Dasypus novemcinctus) are naturally infected with Mycobacterium leprae and have been implicated in zoonotic transmission of leprosy. Early studies found this disease mainly in Texas and Louisiana, but armadillos in the southeastern United States appeared to be free of infection. We screened 645 armadillos from 8 locations in the southeastern United States not known to harbor enzootic leprosy for M. leprae DNA and antibodies. We found M. leprae–infected armadillos at each location, and 106 (16.4%) animals had serologic/PCR evidence of infection. Using single-nucleotide polymorphism variable number tandem repeat genotyping/genome sequencing, we detected M. leprae genotype 3I-2-v1 among 35 armadillos. Seven armadillos harbored a newly identified genotype (3I-2-v15). In comparison, 52 human patients from the same region were infected with 31 M. leprae types. However, 42.3% (22/52) of patients were infected with 1 of the 2 M. leprae genotype strains associated with armadillos. The geographic range and complexity of zoonotic leprosy is expanding.

The fetal-maternal interface of the nine-banded armadillo: endothelial cells of maternal sinus are partially replaced by trophoblast

BACKGROUND

The evolution of invasive placentation in the stem lineage of eutherian mammals entailed resolution of the incompatibility between a semi-allogenic fetus and the maternal immune system. The haemochorial placenta of nine-banded armadillo (Dasypus novemcinctus) is thought to conceal itself from the maternal immune system to some degree by developing inside a preformed blood sinus, with minimal contact with the uterine connective tissue. In the present study, we elucidate the micro-anatomical relationship between fetal and maternal tissue of the nine-banded armadillo using histochemical and immunohistochemical tools.

RESULTS

We conclude that the chorio-allantoic villi are separated from the myometrium by a vascular endothelial layer, as previously proposed. However, we also observe that the trophoblast cells establish direct contact with the endometrial stroma on the luminal side of the endometrium by partially replacing the endothelial lining of the sinus. Further, we demonstrate the presence of leukocytes, perhaps entrapped, in the placental fibrinoids at the interface between the intervillous space and the endometrial arcade.

CONCLUSIONS

The trophoblast of the armadillo invades the uterine tissue to a greater extent than was previously believed. We discuss the implications of this finding for the fetal-maternal immune tolerance.

Metal accumulation in wild-caught opossum

The Virginia opossum (Didelphis virginiana) is widespread in the USA, ranging south through Latin America. The ecology of opossums is such that they are in frequent contact with soils, suggesting that they may function as a valuable bioindicator for chemical contamination in terrestrial environments. Surprisingly, there have been virtually no toxicology studies on opossums. Here, we provide the first analysis of metal contaminants in opossum liver tissues. Liver samples were obtained from 471 opossums, collected from 2003 to 2006, at four sites in North Florida and South Georgia, USA, and concentrations of copper, lead, nickel, selenium, and zinc were measured. We found little evidence of age differences in the concentration of any of the metals. However, there were at least some significant differences between years, males and females, and between sites for each metal, although the pattern of these differences was not always consistent across metals. Concentrations of metals in liver tissue were positively correlated with one another, primarily of each metal (except Pb) with zinc. Reference levels of metal contaminants are not available for opossums, but concentrations of Cu, Ni, Pb, and Zn in our samples were for the most part significantly higher than those reported from liver tissues of nine-banded armadillos (Dasypus novemcinctus) collected at the same sites and in the same years. Data from other small mammals studied elsewhere further indicate that metal concentrations in opossums were high, but at this time, it is not possible to determine if these elevated levels generated toxicity. The substantial temporal and spatial variation we found in metal concentrations suggests that determination of baseline levels for opossums may not be straightforward. Nonetheless, this is the first study quantifying metal accumulation in the livers of Didelphis virginiana and, as such, provides an important starting point for future research.

PATTERNS OF MYCOBACTERIUM LEPRAE INFECTION IN WILD NINE-BANDED ARMADILLOS (DASYPUS NOVEMCINCTUS) IN MISSISSIPPI, USA

The nine-banded armadillo ( Dasypus novemcinctus ) is the only known nonhuman reservoir of Mycobacterium leprae , the causative agent of Hansen's disease or leprosy. We conducted a 6-yr study on a wild population of armadillos in western Mississippi that was exposed to M. leprae to evaluate the importance of demographic and spatial risk factors on individual antibody status. We found that spatially derived covariates were not predictive of antibody status. Furthermore, analyses revealed no evidence of clustering by antibody-positive individuals. Lactating females and adult males had higher odds of being antibody positive than did nonlactating females. No juveniles or yearlings were antibody positive. Results of these analyses support the hypothesis that M. leprae infection patterns are spatially homogeneous within this armadillo population. Further research related to movement patterns, contact among individuals, antibody status, and environmental factors could help address hypotheses related to the role of environmental transmission on M. leprae infection and the mechanisms underlying the differential infection patterns among demographic groups.

SQUAMOUS CELL CARCINOMA IN A NINE-BANDED ARMADILLO (DASYPUS NOVEMCINCTUS)

Squamous cell carcinomas (SCCs) are tumors that occur in most animals and show strong invasiveness into surrounding tissues and nearby osseous tissues. This report describes a case of SCC in a 5-yr-old female nine-banded armadillo (Dasypus novemcinctus) with a hemorrhagic mass on the left mandibular region. The tumor originated in skin tissues and showed invasion of the oral cavity, adjacent to the submandibular salivary gland histologically. To our knowledge, this is the first report of a SCC in a nine-banded armadillo.