Echinocephalus inserratus sp. n. (Nematoda: Gnathostomatidae) from the stingray Pastinachus ater (Dasyatidae) and new records of congeneric and some other nematode larvae from teleost fishes off New Caledonia.

Based on light and electron microscopical studies, a new nematode parasite, Echinocephalus inserratus sp. n. (Spirurida: Gnathostomatidae), is described from the spiral valve of the broad cowtail stingray Pastinachus ater (Macleay) (Dasyatidae, Myliobatiformes) from off New Caledonia. The new species is morphologically and biometrically most similar to Echinocephalus overstreeti Deardorff et Ko, 1983, differing from it mainly in the absence of serrations on the posterior parts of pseudolabia and on interlabia, and in having a longer gubernaculum (150-299 µm long). Morphologically unidentifiable, mostly encapsulated larvae of Echinocephalus spp. were recorded from the following six species of teleost fishes collected in New Caledonian waters, serving as paratenic hosts: Perciformes: Acanthopagrus berda (Forsskål) (Sparidae) and Nemipterus furcosus (Valenciennes) (Nemipteridae); Tetraodontiformes: Abalistes stellatus (Anonymous), Pseudobalistes fuscus (Bloch et Schneider) (both Balistidae), Lagocephalus sceleratus (Gmelin) (Tetraodontidae) and Aluterus monoceros (Linnaeus) (Monacanthidae). Co-parasitising larvae of Ascarophis sp. and Hysterothylacium sp. were also collected from P. fuscus. All these findings represent new host and geographical records. A key to valid species of Echinocephalus Molin, 1858 is provided.

Morphological and molecular characterization of Spirocerca lupi (Nematoda: Spirocercidae) from domestic dogs in Vietnam with reference to Spirocerca vulpis.

Spirocerca lupi is a common parasitic nematode associated with esophageal cancer of canids. Recent surveys have revealed an increasing number of canids infected with Spirocerca spp. in Africa, the Americas, Europe and Western Asia, and described a new species, Spirocerca vulpis, from red foxes (Vulpes vulpes). However, in Southeast Asia, research on Spirocerca spp. is scarce. Therefore, the aim of this study is to explore Spirocerca infection in domestic dogs in Vietnam and to identify the Spirocerca species by analyzing their morphometric and molecular data. We found Spirocerca spp. specimens in 51 (17.7%) out of 287 dogs examined with the intensity of infection ranging from one to 29 nematodes per dog. These nematodes were morphologically and molecularly identified as S. lupi. For morphology, the presence/absence of teeth, the ratio of glandular to muscular esophagus lengths, and the position of the vulva opening of S. lupi and S. vulpis varied between reports, suggesting caution in identification of Spirocerca species based exclusively on morphological characteristics. The molecular analysis based on a partial cox1 sequence revealed that S. lupi from Vietnam is genetically close to those from India and China, but far different from those of Israel, South Africa, Peru and Hungary. Given high genetic and morphological variations, more extensive surveys on Spirocerca spp. from various mammalian hosts at a greater scale are necessary to elucidate the divergence of this nematode.

Thelaziosis due to Thelazia callipaeda in Europe in the 21st century-A review.

Thelazia callipaeda was first described at the beginning of the 20th century in Asia, but this eyeworm is now frequently reported in Europe in the 21st century. To date, thelaziosis has been described in the following European countries (in order of appearance): Italy, France, Germany, Switzerland, Spain, Portugal, Belgium, Bosnia and Herzegovina, Croatia, Serbia, Romania, Greece, Bulgaria, Hungary, Slovakia, the United Kingdom, Turkey and Austria. The infected vertebrate host species include domestic carnivores (dogs and cats), wild carnivores (red foxes, wolves, beech martens, wildcats and golden jackals), lagomorphs (brown hares and wild European rabbits) and humans. In Europe, 11 cases of human thelaziosis have been reported, the majority of which are autochthonous. However, some of them have been imported, a fact which highlights the importance of surveillance policies to restrict cross-border spread of the parasite. The objectives of this article are to review key aspects of the epidemiology of T. callipaeda, summarise animal and human cases in Europe and emphasise the importance of education and awareness among veterinarians, physicians (particularly ophthalmologists) and animal, in order to owners to tackle this zoonosis.

Nematode Thelazia callipaeda is spreading across Europe. The first survey of red foxes from Slovakia.

Canine thalaziosis caused by the spirurid nematode Thelazia callipaeda has started to spread across Western and Central Europe during the last decade. In Slovakia, the first autochthonous cases of this infection were recorded in 2016 in four dogs from the south-eastern part of the country. In August 2017 other autochthonous case, again from the same locality, was reported. Seeing that red foxes are considered the main reservoir hosts for T. callipaeda, their examination could provide an integrated view of the real parasite distribution. Within the present study, 523 red foxes were examined by necropsy, and T. callipaeda nematodes were recovered from the conjunctival sacs of 7 animals, which represents an overall positivity of 1.3%. Six infected foxes originated in eastern Slovakia, which is consistent with the area where positive dogs were recently found. Also, single positive red fox was found in north-western Slovakia. Regarding morphology and morphometry, the specimens recovered from the foxes in this study were evaluated as larger in size when compared to nematodes isolated from Slovak dogs as well as dogs and foxes from other studies. BLAST analyses of the cox1 gene showed that all specimens isolated from Slovak red foxes were identified as haplotype 1 which circulated also in other European countries. Considering that majority of the infected animals, dogs and foxes, came from Kosice region, we can presume that this area might become endemic in a short period of time.

Thelazia callipaeda infection in a 5-month-old infant.

BACKGROUND: Thelazia callipaeda is the main causative organism in thelaziasis, commonly infecting orbital cavities and associated tissues of carnivores. Thelazia callipaeda infection is rarely reported in humans, especially in infants. CASE PRESENTATION: A 5-month-old male infant presented with 2 weeks of redness and increased secretions in the left eye. On examination, the left eye revealed the presence of one creamy thread-like mobile worm in the conjunctival sac. During surgical exploration, a total of 11 worms were extracted from the left eye. The worms were morphologically identified as seven female and four male T. callipaeda. Ocular symptoms resolved rapidly after the removal of the worms, with no recurrence after the 6-month follow-up. CONCLUSION: We present here detailed clinical and morphological information pertaining to T. callipaeda infection, which is considered to be a probably neglected parasitic disease of the eye. This case illustrates the importance of including thelaziasis into the differential diagnosis of ocular surface diseases, especially in infant patients.

First autochthonous cases of canine thelaziosis in Slovakia: a new affected area in Central Europe.

BACKGROUND: The spirurid nematode Thelazia callipaeda, also called the "Oriental eyeworm", is the causative agent of canine and human ocular thelaziosis. In the past few years it has started to spread across central Europe and new endemic areas have been established. The present study reports on the first four autochthonous cases of canine ocular thelaziosis in the territory of Slovakia, Central Europe. RESULTS: All cases were recorded in dogs living in eastern Slovakia, near the border with the Ukraine. All worms collected were investigated morphologically and their identification further confirmed at the molecular level by PCR amplification and direct sequencing. Nucleotide sequences of partial T. callipaeda cox1 and 28S rDNA gene fragments isolated from Slovak dogs were submitted to the GenBank database under accession numbers KY476400 and KY476401, respectively. CONCLUSIONS: Considering that all four cases were diagnosed in animals that had never travelled abroad, there is clear evidence of an autochthonous occurrence and thereby the further spread of T. callipaeda across Europe. Moreover, at latitude of 48°N, these cases might be considered as the northernmost recorded cases of autochthonous in western and Central Europe.

New Cases of Thelazia callipaeda Haplotype 1 in Dogs Suggest a Wider Distribution in Romania.

Thelazia callipaeda is an emerging vector-borne zoonotic helminth parasitizing the conjunctival sac of a broad spectrum of definitive hosts, such as dogs, cats, rabbits, wild carnivores, and humans. Its presence is associated with mild to severe ocular disease. Here, we report two new clinical cases in dogs originating from western and southern Romania, with no travel history. On clinical examination, the nematodes were retrieved from the conjunctival sac and identified using morphological keys and molecular tools. Twenty-two adult nematodes (8 males, 14 females) were collected and were identified as T. callipaeda by morphology. The molecular analysis revealed a 100% identity with haplotype h1 of T. callipaeda. This study describes the occurrence of new autochthonous cases of thelaziosis in Romania, reinforcing the spreading trend of this zoonotic eyeworm and highlighting the need for increased awareness among medical and veterinary practitioners. Moreover, we provide additional molecular evidence for the exclusive distribution of haplotype 1 of T. callipaeda in Europe.

Two cases of human thelaziasis as confirmed by mitochondrial cox1 sequencing in China.

Two special cases of human thelaziasis were reported in China: an old farmer with heavy infection by 36 worms and a 7-year-old boy with infection by eight worms. Thelazia callipaeda was morphologically identified and confirmed by mitochondrial cox1 gene sequencing.

The first human case of Thelazia callipaeda infection in Vietnam.

A 26-year-old man residing in a village of Thai Nguyen Province, North Vietnam, visited the Thai Nguyen Provincial Hospital in July 2008. He felt a bulge-sticking pain in his left eye and extracted 5 small nematode worms by himself half a day before visiting the hospital. Two more worms were extracted from his left eye by a medical doctor, and they were morphologically observed and genetically analyzed on the mitochondrial cytochrome c oxidase 1 gene. The worms were 1 male and 1 female, and genetically identical with those of Thelazia callipaeda. By the present study, the presence of human T. callipaeda infection is first reported in Vietnam.

The First Human Case of Thelazia callipaeda Infection in Vietnam

A 26-year-old man residing in a village of Thai Nguyen Province, North Vietnam, visited the Thai Nguyen Provincial Hospital in July 2008. He felt a bulge-sticking pain in his left eye and extracted 5 small nematode worms by himself half a day before visiting the hospital. Two more worms were extracted from his left eye by a medical doctor, and they were morphologically observed and genetically analyzed on the mitochondrial cytochrome c oxidase 1 gene. The worms were 1 male and 1 female, and genetically identical with those of Thelazia callipaeda. By the present study, the presence of human T. callipaeda infection is first reported in Vietnam.

Thelazia callipaeda: infection in dogs: a new parasite for Spain.

BACKGROUND: Thelazia callipaeda (Spirurida, Thelaziidae), eyeworms, are known as the causative agents of thelaziosis, initially described in Asia and, later on, over the last decade, also in some European countries (e.g., Italy, France, Germany and Switzerland). In June 2010, the first case of canine thelaziosis was observed in central western Spain (La Vera region, Cáceres) and subsequent epidemiological investigation is reported in the present study. RESULTS: This study describes the first autochthonous cases of infection by T. callipaeda in dogs from central western Spain where the first case of eyeworm infection was reported.A total of 456 dogs was examined in this geographical area. Thelazia callipaeda eyeworms were observed in 182 (39.9%) animals, of which 28 showed apparent clinical signs (i.e., conjunctivitis, oedema, epiphora and petechiae). A total of 762 adult nematodes (214 males, 548 females; mean infection rate of 4.18; SD 4.74) were collected with cotton swabs or by flushing of the conjunctival sac of infected animals using physiological saline solution. Nematodes were identified as T. callipaeda according to the morphological keys and molecular analysis of sequences of a portion of the mitochondrial cytochrome c oxidase subunit 1 (cox 1) gene. The sequences were identical to those representing T. callipaeda haplotype 1, previously reported in Europe. CONCLUSIONS: The high infection rate of canine thelaziosis herein reported suggests that practitioners should include this eye infection amongst differential diagnoses of ocular diseases in dogs from this area of Spain or those moving across this area of Spain. Based on the high infection prevalence recorded, the potential public health risk to humans from this region is also discussed.

Human thelaziasis, Europe.

Thelazia callipaeda eyeworm is a nematode transmitted by drosophilid flies to carnivores in Europe. It has also been reported in the Far East in humans. We report T. callipaeda infection in 4 human patients in Italy and France.

Nematode biology and larval development of Thelazia callipaeda (Spirurida, Thelaziidae) in the drosophilid intermediate host in Europe and China.

Thelazia callipaeda, commonly known as the 'oriental eyeworm', has been recently reported in Italy and other European countries. The insect/s that act as intermediate hosts and details of larval development inside the vector remain unclear. In order to (1) demonstrate the species of fly that may act as vector/s for T. callipaeda in southern Italy (Site A) and China (Site B) and (2) describe the larval development of the nematode in the body of flies, 847 Phortica (Drosophilidae) flies were collected from the above two sites, each with a history of human and/or canine thelaziosis. Flies were identified as Phortica variegata (245 - site A) and Phortica okadai (602 - site B), experimentally infected by 1st-stage larvae (L1), kept at different temperatures and dissected daily until day 180 post-infection (p.i.). Dead flies from site A were subjected to specific polymerase chain reaction (PCR) assay to detect T. callipaeda. To demonstrate the role of Phortica as vectors of T. callipaeda, 3rd-stage larvae (L3) recovered from the proboscis of flies were deposited onto the cornea of the eyes of dogs and rabbits. Following dissection, 3 (2.9%) of P. variegata in site A were found to be infected by L3 in the proboscis on days +14, +21 and +53 p.i., compared with 26 (18.4%) of Phortica flies recorded as being positive by PCR. Sequences from positive PCR products were 99% identical to sequences of the corresponding species available in GenBank (AY207464). At site B, 106 (17.6%) of 602 dissected P. okadai were found to be infected by T. callipaeda larvae (different stages) and in total 62 L3 were recovered from the proboscis of 34 (5.6%) flies. The shortest time in which L3 were found was at day +14, +17, +19, and +50 p.i. respectively, depending on the environmental temperatures. Of 30 flies overwintered for 6 months, 6 L3 were detected at day +180 p.i. in 3 flies (10%). The biology of larval development was reconstructed on the basis of the dissection of 602 P. okadai-infected flies and the morphology of larval stages in the insect body described. The present work provides evidence that P. variegata and P. okadai act as vectors for T. callipaeda in southern Europe and in China, respectively. The phenomenon of overwintering is described here for the first time for T. callipaeda and discussed. Finally, the relationship between T. callipaeda and its fly vector is considered in light of disease prophylaxis and to model its dissemination into habitats and environments favourable to Phortica flies.

Paraspiralatus sakeri n. g., n. sp. (Nematoda: Spiruroidea, Spirocercidae) from saker falcons, Falco cherrug in Saudi Arabia and the first report of larvae from the subcutaneous tissues of houbara bustards, Chlamydotis undulata macqueeni in Pakistan.

A new nematode genus and species, Paraspiralatus sakeri, is described from the stomach of a wild-caught, female saker falcon in Saudi Arabia. This spirurid differs from the nearest genus and species Spiralatus baeri Chabaud, Brygoo & Durette, 1963 in the shape of the pseudolabia, shape of the buccal capsule and absence of a large cephalic vesicle. In addition, third stage spirurid larvae were recovered for the first time from subcutaneous tissues of two houbara bustards. These had died in the Rahim Yar Khan Rehabilitation Center (Houbara Foundation International, Lahore, Pakistan) in Pakistan and were examined at the National Avian Research Center in the United Arab Emirates. The morphology of the larvae and host pathology are described. Comparative studies with the adult spirurids from the saker falcon showed each to have similar cephalic and pharyngeal morphological features to the adults described indicating they are probably the same species. Spirurid nematodes of the suborder Spirurina normally have an arthropod intermediate host. In view of the host, the site from which the larvae were recovered and the fact that this is a rare occurrence, the houbara bustard is considered to be a paratenic host.

First report of Thelazia sp. from a captive Oriental white stork (Ciconia boyciana) in Japan.

Nematodes of the genus Thelazia were recovered from the cornea and inferior conjunctival sac of an immature Oriental white stork (Ciconia boyciana). The bird hatched and reared at the Toyooka Oriental White Stork Breeding Center, Hyogo Prefecture, Japan, but died of chlamydiosis. There were neither gross nor histopathologic ophthalmic lesions. The eye worm from a bird is believed to be first reported in Japan. As regarding reintroduction plan for the Oriental white stork, control measures for prevent further infection with the eye worm will be needed.

Studies on the developmental cycle of Trichospirura leptostoma (Nematoda: Thelaziidae). Experimental infection of the intermediate hosts Blatella germanica and Supella longipalpa and the definitive host Callithrix jacchus and development in the intermediate hosts.

The cockroaches Blatella germanica and Supella longipalpa can act as intermediate hosts of Trichospirura leptostoma as demonstrated by experimental infestation. The parasite developed from the embryonated egg into the infective larval stage (L3) in cockroaches within 5-6 weeks. After experimental infection of marmosets (Callithrix jacchus), eggs were first found in faecal samples (prepatency) at 8-9 weeks post-infection. Patency lasts about 2 years. Despite the presence of living adult worms in the marmosets' pancreas, no additional eggs were observed in their faeces after the patent period.

On Thelazia anolabiata (Molin, 1860) Railliet & Henry, 1910 (Nematoda, Thelazioidea): a new host record and systematic considerations

Thelazia anolabiata (Molin, 1860) Raillet & Henry, 1910, parasite of eyes of birds, is reported in s new host, Ortalis canicolis pantanalensis Cher & Reich from Salobra, Mato Grosso do Sul State; T. digitata Travassos, 1918 and T. lutzi Travassos, 1918 are considered its synonyms

Two human cases of gnathostomiasis and discovery of a second intermediate host of Gnathostoma nipponicum in Japan.

Two human cases of gnathostomiasis from ingestion of raw native Japanese loaches, Misgurnus anguillicaudatus, are reported. Seven early third-stage larval Gnathostoma nipponicum were recovered from 3,098 loaches in the same district in which 2 human patients had obtained and eaten raw loaches. Encapsulated G. nipponicum larvae were also recovered from loaches infected under laboratory conditions. All 6 weasels captured in the same district in which the naturally infected loaches were found and where the humans had become infected were infected with adult worms of the same species. This is the first report of M. anguillicaudatus serving as a second intermediate host of G. nipponicum.

A brief report on Gnathostoma spinigerum specimens obtained from human cases.

A total of 23 gnathostome specimens different stages from the Hospital for Tropical Diseases, other general hospitals and medical clinics in Bangkok metropolitan area and central Thailand were identified as G. spinigerum. The various stages were as follows: Five advanced third-stage larvae (22.0%) of various sizes; 2.20-3.50 mm X 0.40-0.63 mm were removed from the skin, mucous membrane and the eyeball, of which the smallest measured 2.20 X 0.40 mm. Fourteen immature worms of both sexes were from the skin and mucous membrane, one spontaneously voided in the urine. The sizes varied from 4.63-9.35 mm X 0.60- 1.05 mm (8 male worms), and 3.83-16.25 mm. X 0.83-1.0 mm (6 female worms). All these immature worms had 8 rows of complete cephalic-hooklets with the exception of two with 6 and 7 rows of complete cephalic-hooklets. Four mature males size ranged from 9.9-12.5 mm X 1.0-1.25 mm. The smallest was removed from the abdominal skin of a newly born 7-day old baby evidently the case was prenatally transmitted.