Maria Interisano

Genetic variability of Echinococcus granulosus sensu stricto in Europe inferred by mitochondrial DNA sequences

The genetic diversity of Echinococcus granulosus sensu stricto (s.s.) metacestodes from four European countries was evaluated by the DNA sequence analysis of the cytochrome c oxidase subunit 1 (cox1) mitochondrial gene. Of the 312 organisms investigated, 132 were from Bulgaria, 35 from Hungary, 89 from Italy and 56 from Romania. Considerable intraspecific variation was observed in the mitochondrial cox1 sequences: 24 haplotypes were detected in the Eastern European population and seven in the Italian population. The Eastern European population parsimony network displayed a star-like features consisting of the most common haplotype EG1 (G1 genotype) and the three major haplotypes: EG2, EG3 and EG4. The EG1 was also the major haplotype in the Italian population network, though with a higher prevalence (73%) compared to the Eastern European network. The percentage of the population constituted by the G1 genotype was used as an indirect index to evaluate the genetic diversity within E. granulosus s.s. populations of Eurasia. A clinal correlation between the percentage of the G1 genotype and the geographical regions of Eurasia was observed: the G1 genotype is highly represented in the Mediterranean Basin; it decreases in Eastern Europe and South-West Asia and increases in China. This clinal correlation could reflect the spreading of livestock domestication from Southern-Western Asia during the Neolithic period, beginning around 12,000 BC.

First insights into the genetic diversity of Echinococcus granulosus sensu stricto (s.s.) in Serbia.

Cystic echinococcosis (CE) caused by Echinococcus granulosus sensu stricto (s.s.) is a cosmopolitan zoonotic infection which is endemic in Serbia where it is subject to mandatory reporting. However, information on the incidence of the disease in humans and prevalence of hydatid infection in livestock remains limited. We used sequenced data of the cytochrome c oxidase subunit 1 (cox 1) mitochondrial gene to examine the genetic diversity and population structure of E. granulosus (s.s.) from intermediate hosts from Serbia. We also compared our generated nucleotide sequences with those reported for neighbouring European countries. Echinococcus canadensis was molecularly confirmed from pig and human hydatid isolates. E. granulosus (G1) was confirmed from sheep and cattle hydatid isolates as well as the first molecular confirmation in Serbia of E. granulosus G2 in sheep and E. granulosus G3 in sheep and cattle hydatid isolates. The Serbian E. granulosus (s.s.) parsimony network displayed 2 main haplotypes (SB02 and SB05) which together with the neutrality indices were suggestive of bottleneck and/or balancing selection. Haplotype analysis showed the presence of the common E. granulosus haplotype described from other worldwide regions. Investigation of the pairwise fixation (Fst) index suggested that Serbian populations of E. granulosus (s.s.) from sheep and cattle hosts showed moderate genetic differentiation. Six of the Serbian haplotypes (SB02-SB07) were shared with haplotypes from Bulgaria, Hungary and/or Romania. Further studies using a larger number of hydatid isolates from various locations across Serbia will provide more information on the genetic structure of E. granulosus (s.s.) within this region.

High prevalence of Trichinella pseudospiralis in Florida panthers (Puma concolor coryi)

BackgroundParasites of the genus Trichinella are zoonotic nematodes common in carnivores throughout the world. We determined the prevalence and species of Trichinella infections in Florida panthers (Puma concolor coryi).MethodsTongues from Florida panthers were collected at necropsy and examined by pepsin-HCl artificial digestion for infection with Trichinella spp. DNA was extracted from larvae and multiplex PCR using Trichinella species-specific primers was used to genotype the worms.ResultsTrichinella spp. larvae were detected in 24 of 112 (21.4%; 14.6%–30.3%) panthers. Sixteen of the panthers (14.3%) were infected with T. pseudospiralis, 1 (0.9%) was infected with T. spiralis, and 2 (1.8%) had mixed infections of T. pseudospiralis and T. spiralis. Trichinella spp. larvae from 5 panthers were not identified at the species level due to degraded DNA.ConclusionsThis is the highest prevalence of T. pseudospiralis detected in North America up to now and suggests the Florida panther is a key mammalian reservoir of this parasite in southern Florida. Trichinella pseudospiralis can infect both mammals and birds indicating the source of infection for Florida panthers could be broader than believed; however, birds represent a small percentage (0.01%) of the cat’s diet. Since wild pigs (Sus scrofa) can be parasitized by both T. pseudospiralis and T. spiralis and these swine can comprise a large portion (~40%) of a panther’s diet in Florida, we believe that Florida panthers acquired these zoonotic parasites from feeding on wild pigs.

Molecular identification of nematode larvae different from those of the Trichinella genus detected by muscle digestion

Although larvae of the genus Trichinella are the most common parasite species detected in vertebrate muscles using artificial digestion, nematode larvae belonging to other genera are sometimes detected and incorrectly identified as Trichinella. However, it is often very difficult to identify these larvae at the species, genus or family level using microscopy because of the absence of specific morphological characters or cuticle damage, and the only means of identification is PCR and sequencing of specific molecular markers (12S mtDNA; COI; 18S rDNA; and ITS1). From 2008 to 2011, 18 nematode isolates not belonging to the genus Trichinella were collected from different host species. Eleven of these isolates were successfully identified at the species, genus or superfamily level: larvae from two common kestrels, three hooded crows, a hen harrier and a domestic pig were identified as Toxocara cati; larvae from a badger were identified as Toxocara canis; larvae from a domestic pig were identified as a free-living nematode of the genus Panagrolaimus; larvae from a wild boar were identified as belonging to the Metastrongylus genus; and larvae from a rough-legged buzzard were identified as belonging to the superfamily Filarioidea. The recovery of nematodes belonging to genera other than Trichinella during routine meat inspection suggests that the persons performing the analyses need to be informed of the possibility of false positives and that a molecular-based identification system that allows for a rapid and reliable response must be adopted (i.e., a DNA barcoding-like system).

Epidemiological Study of Cystic Echinococcosis in Sheep, Cattle and Goats in Erbil Province

Cystic echinococcosis (CE) or hydatid cyst (HC) caused by the larval stage of the tapeworm Echinococcus granulosus continues to be a substantial cause of morbidity and mortality in many parts of the world. Since Kurdistan region is considered as endemic area, an epidemiological study was conducted to investigate the occurrence of CE isolated from sheep, cattle and goats from July 2013 to June 2014. The total rate of infection was 11.17(457/4092), with the highest rate (9.07%) in sheep and the lowest (0.54%) in goats. Regarding the sex of the infected animals, female showed slightly a higher rate than males (5.99% versus 5.18%) which statistically non-significant (P>0.05). Among the three intermediate host sheep showed the highest rate of infection (14.51%) regarding the sex females of sheep and cattle showed higher rate of infection versus males (27.36 and 20.35 versus 9.37 and 3.86). Furthermore, the highest incidence of CE in sheep, cattle and goats were found among the age group over three years (18.75, 5.41 and 1.69%, respectively), while the lowest rate was noted in the age groups less than one year (3.96 and 0.25%, o.33, respectively). On the other hand, sheep showed high rate of infection throughout the year with peaks during May to July which were 19.44%, 17.59 and 18.14%,respectively. This was followed by cattle and goats (11.67% and 5.26%) in April and December, respectively. Regarding the size, the higher numbers of small sized cysts were found in the liver (98/175), while the highest numbers of large sized cysts were found in both liver and lung which were 69/165. The liver and lungs appeared to be the site of predilection, since highest rate of infection was reported in these organs. Regarding the fertility of CE, the highest was in sheep (87.6%), followed by goats (77.27%) and then the cattle (40.63%).

Detection and correlates of Chlamydophila pneumoniae among children with acute respiratory infections

Acute respiratory infections (ARI) are the leading cause of pediatric morbidity and mortality worldwide. Information on etiological agents of ARI in developing countries is still limited. This study conducted in Alexandria, Egypt, was designed to determine the prevalence of several microorganisms in 113 children hospitalized with ARI. Overall, 65 agents were identified; 58 (51.3%) individuals were found to be positive for at least one pathogen, and seven of them were also positive for two agents. Chlamydophila pneumoniae was the most commonly detected agent (n = 32; 28.3%), followed by Mycoplasma pneumoniae, respiratory syncytial and influenza. Positivity for C. pneumoniae, which was the most commonly detected agent, was associated with male sex and with mild disease of the upper respiratory tract.

A Morphologically Unusual Echinococcus granulosus (G1 Genotype) Cyst in a Cow from Kurdistan - Iraq

Cystic (CE) and alveolar (AE) echinococcosis caused by the metacestode larval stage of Echinococcus granulosus sensu lato and Echinococcus multilocularis respectively are globally distributed zoonotic infections of public health importance. Molecular techniques have proven to be invaluable tools in the study of Echinococcus species. However, prior to the advent of DNA approaches and their routine application, morphological identification of E. multilocularis was reported from aberrant intermediate hosts such as cattle from various geographical locations. During a routine veterinary inspection at the Sulaimani Province abattoir (Kurdistan region, Iraq), an unusual echinococcal cyst embedded within a dense stroma resembling an E. multilocularis infection was observed in a cow liver. DNA amplification and analysis of a fragment within the cytochrome c oxidase subunit 1 (cox 1) mitochondrial gene revealed that the infection was caused by Echinococcus granulosus (G1 genotype). This finding highlights the importance of DNA molecular confirmatory tests to differentiate between cystic and alveolar echinococcosis particularly in areas where the latter disease is rare.

Detection of Trichinella murrelli in coyotes (Canis latrans) from Oklahoma and North Texas.

We determined the prevalence and mean intensity of Trichinella sp. infection in coyotes from six counties in Oklahoma and one in northern Texas. Tongues from 77 coyotes were examined using histology and artificial tissue digestion. Histological examination showed a prevalence of 3.9% (3 of 77) whereas the prevalence was 6.5% (5 of 77) based on artificial digestion of 5.0 g of muscle from coyote tongues. One sample was positive for Trichinella sp. on histology but negative by artificial digestion. Combining data from both diagnostic techniques showed that six of 77 (7.8%) coyotes were infected with Trichinella spp. The mean intensity of Trichinella sp. larvae ranged from 0.2 to 66.2 with an average of 16.0 larvae per gram (LPG) of tongue. Genotyping results demonstrated that the coyotes were infected with Trichinella murrelli. This is the first report of T. murrelli infection in coyotes in Oklahoma. T. murrelli had previously been isolated from coyotes in Texas.

The occurrence of Trichinella species in the cougar Puma concolor couguar from the state of Colorado and other regions of North and South America.

Trichinella species are zoonotic nematodes that infect wild carnivores and omnivores throughout the world. We examined the prevalence and species of Trichinella infections in cougars (Puma concolor couguar) from Colorado, United States. Tongues from cougars were examined by pepsin-HCl artificial digestion to detect Trichinella spp. larvae. The species or genotype of individual worms was identified by multiplex polymerase chain reaction (PCR). Trichinella spp. larvae were detected in 17 of 39 cougars (43.6% (28.7-59.5%)). Five of the cougars (12.8%) were infected with T. murrelli, 3 (7.7%) were infected with T. pseudospiralis, and 1 (2.6%) had Trichinella genotype T6. Trichinella spp. larvae from eight cougars were not identified at the species level, due to degraded DNA. The high prevalence of Trichinella spp. in cougars from Colorado and reports of the parasite in other populations of Puma spp. suggest that this large predator is a key mammalian reservoir.

Trichinella spiralis a new alien parasite in Italy and the increased risk of infection for domestic and wild swine

In Europe, Trichinella spiralis, the most dangerous species for humans of the genus Trichinella, has a patchy distribution with important foci in Eastern countries and Spain. This zoonotic pathogen was apparently not circulating among wild and domestic animals of Italy. In 2016, muscle larvae belonging to this nematode species were detected in a red fox (Vulpes vulpes) shot in the Piacenza province (Northern Italy). This parasite may have been introduced into northern Italy from eastern Europe by hunters, by a hunting dog, or by immigrants, who illegally carried infected meat in their personal baggage. In the same year, T. spiralis infected sausages illegally introduced by personal baggage into Italy from Romania, were inadequately disposed of in the garbage of a central Italian town. Even though these two episodes may not be connected in time and space, they represent an increased risk of infection for domestic and wild swine, which are highly susceptible to this pathogen. In these animals, T. spiralis shows a higher larval burden and a longer survival time than other Trichinella species. Since most of the Italian pig production plants are in northern Italy, the circulation of T. spiralis should be strictly monitored in wildlife living in these areas.