Survey of coyotes, red foxes and wolves from Wyoming, USA, for Echinococcus granulosus s. l

Echinococcus granulosus Sensu Stricto and Echinococcus multilocularis in a Gray Wolf (Canis lupus) in Turkey: Further Evidence for Increased Risk of Alveolar Echinococcosis in Urban Areas

OBJECTIVE

The aim of this study was to identify Echinococcus species by morphological and molecular means.

METHODS

A dead gray wolf (Canis lupus) was found near Erzurum province and brought to the parasitology laboratory. Sedimentation and counting technique (SCT) and polymerase chain reaction (PCR) analysis were conducted.

RESULTS

The SCT implications indicated that the wolf had a substantial worm burden (62,720 and 49,280 parasites) due to a co-infection of E. granulosus s.l. and E. multilocularis. Genus/species-specific PCR was used to analyze DNA extracted from adult worms and confirmed as E. granulosus s.s. and E. multilocularis, utilizing COI and 12S rRNA gene sequence analysis, respectively.

CONCLUSION

This report presents the first co-detection of E. granulosus s.s. and E. multilocularis in a gray wolf found in an urban area in a highly endemic area for human echinococcosis in northeastern Turkey. The results emphasize that AE is not only a problem of rural areas, but also occurs in urban areas, which may pose a threat to public health. Therefore, surveillance in urban areas is crucial. The need to develop new control strategies for domestic and wildlife in the study area is also highlighted.

Cystic echinococcosis in cattle and sheep caused by Echinococcus granulosus sensu stricto genotypes G1 and G3 in the USA

BACKGROUND

Endemic domestic dog-ruminant cycles and human cystic echinococcosis caused by Echinococcus granulosus have been sporadically reported in the United States. However, there is a paucity of molecular data describing the genotypes and haplotypes of this important cestode in domestic ruminant hosts.

METHODS

Ninety-four cysts from the lungs and/or livers of slaughtered beef cattle (76 samples), dairy cows (five samples) and sheep (13 samples) were collected from abattoirs in four states of the USA. Samples were genotyped at two mitochondrial loci, cox1 and nad5. Sequences were used to determine species, genotypes and haplotypes using median joining networks and Bayesian phylogenetic analyses. Cyst fertility was assessed in hematoxylin and eosin-stained sections. Additionally, previously reported autochthonous E. granulosus infections in the USA in various hosts were mapped.

RESULTS

Based on cox1 sequences obtained from 94 cysts, 89 (94.7%) were identified as E. granulosus G1/G3, while five (5.3%) were Taenia hydatigena. Taenia hydatigena were only isolated from sheep. Based on nad5 sequences obtained from 89 hydatid cysts, 96.6% and 3.4% belonged to E. granulosus sensu stricto genotypes G1 and G3 respectively. Two haplotypes were found among E. granulosus cox1 sequences, neither of which was geographically unique. Six haplotypes were found among nad5 sequences in genotype G1, of which five were novel, while one haplotype was found in genotype G3. In the concatenated cox1-nad5 dataset, seven haplotypes were identified, of which six were geographically unique. All cysts from cattle were non-fertile. Four cysts from sheep were fertile.

CONCLUSIONS

All genotyped samples belonged to E. granulosus s.s. This is the first study to our knowledge to confirm the presence of genotypes G1 and G3 in domestic cattle and sheep intermediate hosts in the USA and provide data for future diagnostic and epidemiological studies. Sequences have been deposited in GenBank (cox1 sequences: OR398494-OR398496, nad5 sequences: OR400695-OR400702).

Evaluating noninvasive methods for estimating cestode prevalence in a wild carnivore population

Helminth infections are cryptic and can be difficult to study in wildlife species. Helminth research in wildlife hosts has historically required invasive animal handling and necropsy, while results from noninvasive parasite research, like scat analysis, may not be possible at the helminth species or individual host levels. To increase the utility of noninvasive sampling, individual hosts can be identified by applying molecular methods. This allows for longitudinal sampling of known hosts and can be paired with individual-level covariates. Here we evaluate a combination of methods and existing long-term monitoring data to identify patterns of cestode infections in gray wolves in Yellowstone National Park. Our goals were: (1) Identify the species and apparent prevalence of cestodes infecting Yellowstone wolves; (2) Assess the relationships between wolf biological and social characteristics and cestode infections; (3) Examine how wolf samples were affected by environmental conditions with respect to the success of individual genotyping. We collected over 200 wolf scats from 2018-2020 and conducted laboratory analyses including individual wolf genotyping, sex identification, cestode identification, and fecal glucocorticoid measurements. Wolf genotyping success rate was 45%, which was higher in the winter but decreased with higher precipitation and as more time elapsed between scat deposit and collection. One cestode species was detected in 28% of all fecal samples, and 38% of known individuals. The most common infection was Echinococcus granulosus sensu lato (primarily E. canadensis). Adult wolves had 4x greater odds of having a cestode infection than pups, as well as wolves sampled in the winter. Our methods provide an alternative approach to estimate cestode prevalence and to linking parasites to known individuals in a wild host system, but may be most useful when employed in existing study systems and when field collections are designed to minimize the time between fecal deposition and collection.

The First Record of Echinococcus ortleppi (G5) Tapeworms in Grey Wolf (Canis lupus)

The aim of this study is to confirm the presence and molecular identification of Echinococcus tapeworms in wolves from south-eastern Poland. An investigation was carried out on the intestines of 13 wolves from south-eastern Poland. The small intestines were divided into three equal segments. Each segment was separately examined using the sedimentation and counting technique (SCT). The detected Echinococcus tapeworms were isolated and identified by PCRs and sequencing (nad1 and cox1 genes). Additionally, DNA isolated from the feces of wolves positive for Echinococcus tapeworms was examined with two diagnostic PCRs. The intestines of one wolf were positive for E. granulosus s.l. when assessed by SCT; the intestine was from a six-year-old male wolf killed in a communication accident. We detected 61 adult tapeworms: 42 in the anterior, 14 in the middle, and 5 in the posterior parts of the small intestine. The PCRs conducted for cox1 and nad1 produced specific products. A sequence comparison with the GenBank database showed similarity to the deposited E. ortleppi (G5) sequences. An analysis of the available phylogenetic sequences showed very little variation within the species of E. ortleppi (G5), and identity ranged from 99.10% to 100.00% in the case of cox1 and from 99.04% to 100.00% in the case of nad1. One of the two diagnostic PCRs used and performed on the feces of Echinococcus-positive animals showed product specific for E. granulosus. This study showed the presence of adult E. ortleppi tapeworms in wolves for the first time.