Acanthocephalan infection and sparganosis in a green tree snake (Dendrelaphis punctulata).

Acanthocephalan and spargana parasites were identified within a body wall mass during exploratory surgery in a wild green tree snake. Acanthocephalan parasites have not previously been reported in this species. Surgical excision, the treatment of choice, could not be achieved because of the extensive infiltration of the coelomic cavity.

Patent Angiostrongylus mackerrasae infection in a black flying fox (Pteropus alecto).

BACKGROUND: A wild adult male black flying fox (Pteropus alecto) was presented unable to fly or hang strongly. RESULTS: Necropsy and histological examination revealed a severe pneumonia, with numerous Angiostrongylus mackerrasae in the pulmonary artery. The pulmonary parenchyma contained numerous eggs and rare larvae. CONCLUSION: This is the first report of patent Angiostrongylus infection in an accidental (i.e. non-Rattus) host species. It is also the first report of A. mackerrasae infection in an accidental host (including flying foxes). Worms recovered from cases of suspected angiostrongyliasis should be examined in morphological detail to ensure correct identification.

Neuroangiostrongyliasis due to Angiostrongylus cantonensis in gang-gang cockatoos (Callocephalon fimbriatum).

CASE REPORT: Four gang-gang cockatoos from an aviary in Sydney displayed severe neurological signs. Three were necropsied and histopathology of the brains and spinal cords revealed migrating nematodes, which were identified as Angiostrongylus cantonensis. The migrating larval nematodes created tracts of malacia in the brain, but elicited little inflammatory cell infiltration. However, adult nematodes that had emerged onto the meningeal surface of the spinal cord evoked a marked non-suppurative reaction. Detailed histological examination of other tissues revealed larvae embedded in arterioles in the gastrointestinal serosa, lung and heart, which were associated with a significant granulomatous response. The latter lesions were consistent with our understanding of the pathogenesis of infection with this parasite, but have not been previously described, probably as a result of limited sampling. CONCLUSIONS: Angiostrongylus cantonensis is still present in the Sydney area and can cause significant disease in exposed animals, including birds. It also highlights potential human health problems.

Neuroangiostrongyliasis and other parasites in tawny frogmouths (Podargus strigoides) in south-eastern Queensland.

The neurological, clinical and pathological findings and endoparasites in 10 wild tawny frogmouths (Podargus strigoides) presented to the Australian Wildlife Hospital in Beerwah, Queensland during a 28-day period in May 2009 are reported. Affected birds had a history of being found in poor body condition on the ground and unable to fly. Clinical examination revealed paresis with variable but generally weakened deep pain responses, withdrawal reflexes and an inability to perch. Severely affected birds that failed to respond to anti-inflammatory, antibiotic and anthelmintic treatments all had larval Angiostrongylus cantonensis in the brain and or spinal cord, with occasional larvae found in the visceral organs. Other parasites detected included the liver fluke, Brachylecithum podargi, the intestinal nematode, Allodapa suctoria, an unidentified species of Trichostrongylus and unidentified cestodes. Gametocytes of Leucocytozoon sp. were found in peripheral blood smears and low numbers of microfilariae were found in histological sections of various blood vessels of several birds. However, no adult filarioids were recovered. Unidentified subcutaneous mites were identified in the connective tissue of the thoracic inlet. Attempts to treat two birds with ivermectin or oxfendazole-praziquantel were unsuccessful, but a third bird treated with a combination of steroidal and non-steroidal anti-inflammatory therapy followed by moxidectin steadily recovered, such that by 6 weeks post presentation its ability to perch, grasp, fly and judge distances was considered normal and it was subsequently released.

Pathology of cutaneous trombidiosis caused by larval trombiculid mites in a wild Lesueur's tree frog (Litoria wilcoxii).

Cutaneous trombidiosis caused by larvae of trombiculid mites (Vercammenia gloriosa and V. zweifelorum) in the skin of a wild tree frog, Litoria wilcoxii, in northern Queensland, Australia manifested as small, domed vesicular lesions on the dorsal and lateral surfaces posterior to the eyes. The lesions contained small, orange trombiculid mites, with a surrounding minimal inflammatory reaction. The general health and behaviour of the frog appeared unaffected. Provisional diagnosis of cutaneous trombidiosis can be made from its distinctive clinical appearance and confirmed by biopsy with direct microscopic examination of mites. This case report represents a new host record.

Yelirella nomen novum for Rileyella Spratt, 2003 (Pentastomida: Cephalobaenida), a junior homonym of Rileyella Townsend, 1909 (Diptera: Tachinidae).

Yelirella nomen novum is proposed as a replacement name for Rileyella Spratt, 2003 (Pentastomida: Cephalobaenida), which is a junior homonym of Rileyella Townsend, 1909 (Diptera: Tachinidae), resulting in the new combination Yelirella petauri (Spratt, 2003) n. comb.

Rileyella petauri gen. nov., sp. nov. (Pentastomida: Cephalobaenida) from the lungs and nasal sinus of Petaurus breviceps (Marsupialia: Petauridae) in Australia.

A new cephalobaenid pentastome, Rileyella petauri gen: nov., sp. nov. from the lungs and nasal sinus of the petaurid marsupial, Petaurus breviceps, is described. It is the smallest adult pentastome known to date, represents the first record of a mammal as the definitive host of a cephalobaenid and may represent the only pentastome known to inhabit the lungs of a mammal through all its instars, with the exception of patent females. Adult males, non-gravid females and nymphs moulting to adults occur in the lungs; gravid females occur in the nasal sinus. R. petauri is minute and possesses morphological features primarily of the Cephalobaenida but the glands in the cephalothorax and the morphology of the copulatory spicules are similar to some members of the remaining pentastomid order, the Porocephalida. This unusual combination of features distinguish the new genus from other genera in the Cephalobaenida. The occurrence of only seven fully-formed larvae in eggs in the uterus, each representing about 10% of the length of the patent female, and her presence in the nasal sinus of a dependent juvenile P. breviceps (36 gm) implies a direct life cycle.

Aspects of the life history of Muspicea borreli (Nematoda: Muspiceidae), parasite of the house mouse (Mus domesticus) in Australia.

Prevalence of Muspicea borreli (Nematoda) infection in wild populations of Mus domesticus in forests in southeastern New South Wales and in rural Canberra, Australia was variable, relatively low and the parasite occurred predominantly in male mice. Experimental infection of BALB/c mice occurred only via subcutaneous inoculation but was achieved using i) adults containing embryonating eggs, ii) adults containing active larvae and iii) active larvae dissected from the uterus of female worms. Experimental infection was not established using adults containing unembryonated eggs and was not established via intraperitoneal, percutaneous nor oral routes. Evidence indicates that larvae develop to the infective stage in the uterus of the adult worm, suggests that an obligate developmental phase on the host skin does not occur and that autoinfection is possible. Experimental infection predominated in males; females rarely became infected. When male BALB/c mice were inoculated subcutaneously with M. borrelia, immediately paired with an uninoculated female and permitted to breed for 90 days, infection was found in male and female offspring only of the second and subsequent litters or in the breeding female partner. Transmission to the young occurred within 21 days of birth and fifth-stage M. borrelia were found in offspring of the second and subsequent litters only after 35 or more days. However, when a male was inoculated but mating delayed for 23 days, infection was found in progeny of the first and second litters. The life cycle is direct and the prepatent period in BALB/c mice is estimated at 50-60 days. The precise mode of transmission of the parasite in breeding pairs of mice was not determined but larvae remained active for approximately an hour in balanced saline solutions (pH = 7.2) and in human saliva but died under conditions emulating free-living (tap water pH = 7.1) and stomach (pepsin solution pH = 2) environments. Transmission was not effected by transplacental, transmammary nor transseminal routes. Consequently, it is difficult not to conclude that transmission may occur via penetration of skin or mucous membranes, and allogrooming behaviour may be particularly important in this regard.

Life history and pathogenesis of Gallegostrongylus australis (Nematoda: Angiostrongylidae) in muridae.

Gallegostrongylus australis Spratt, Haycock & Walter, 2001 (Nematoda: Angiostrongylidae) developed in Deroceras panormitanum, Lehmannia nyctelia, L. flava and Milax gigates (Gastropoda). The first moult occurred at 18-19 days after infection (DAI) and the second moult at 28 DAI. Larvae were infective to experimental murid definitive hosts at 35 DAI. In experimentally infected Rattus fuscipes larvae moulted L3-4 at 3 DAI and L4-5 at 6-7 DAI. Patency in R.fuscipes, R. lutreolus, R. norvegicus and R. rattus occurred 27-64 DAI and duration varied from 7-392 days. Histopathological changes in the lungs of R. lutreolus and development of debilitating clinical signs, in contrast to R. fuscipes, suggests that the former host-parasite relationship may be the more recent one but other traits suggest the opposite. Patent infections were established in some wild R. rattus and some laboratory R. norvegicus but not in wild M. domesticus, laboratory M. musculus, rabbit, Oryctolagus cuniculus, and marsupial bandicoot, Isoodon macrourus.

Gallegostrongylus australis n. sp. (Nematoda: Angiostrongylidae) from Muridae in Australia, with zoogeographical considerations.

Gallegostrongylus australis n. sp. (Nematoda: Angiostrongylidae) is described from subpleural nodules in the lungs of Rattus fuscipes, R. lutreolus and Mus domesticus in Australia. It is distinguished from G. andersoni occurring in gerbillids in West Africa by the shorter lengths of spicules and gubernaculum, and from G. ibicensis occurring in microtids and murids in Spain by the greater lengths of spicules and gubernaculum and the shorter distances from vulva and from anus to the caudal extremity of females. The parasite has been found only in 16 of 4,227 (prevalence 0.38%) animals representing at least 28 species of native and three species of introduced murid rodents throughout Australia. The genus Gallegostrongylus may be an old one, possibly originating in rats. By rafting and/or human activities the parasite appears to have been distributed around the world where it has encountered suitable intermediate hosts and available niches for colonisation of new definitive hosts. Consequently, morphologically similar but biologically distinct species have evolved in rodent hosts in West Africa, the western Mediterranean, and Australia.

Neuro-angiostrongyliasis: unresolved issues.

Angiostrongylus cantonensis, the rat lungworm, probably evolved with its hosts, members of the genus Rattus and closely related species, in south-east Asia. Since its first discovery in rats in China and in a case of human infection in Taiwan, the parasite has been found to infect humans and other mammals across a wide and ever-increasing territory, which now encompasses much of south-east Asia, Melanesia, Polynesia and eastern Australia. It has also established a foothold in Africa, India, the Caribbean and south-eastern USA. This dispersal has been a direct result of human activity, and in some cases has been linked with the spread of the African giant land snail, Achatina fulica. However, this snail is not critical to the extension of the parasite's range, as numerous other indigenous molluscan species serve as adequate intermediate hosts; the importance of Achatina to the life cycle may have been over-emphasized. In Australia, the parasite is established along parts of the east coast, and the presence of an indigenous close relative, Angiostrongylus mackerrasae, suggests a long association of the parasite with its local rat hosts, a situation analogous to that of Angiostrongylus malaysiensis in south-east Asia. These three Angiostrongylus species share virtually the same life cycle, but only A. cantonensis has been confirmed to be a human pathogen.

Mitochondrial DNA polymorphism within and among species of Capillaria sensu lato from Australian marsupials and rodents.

The nucleotide variation in a mitochondrial DNA (mtDNA) fragment within and among species of Capillaria sensu lato from Australian marsupials and rodents was analyzed using a mutation scanning/sequencing approach. The fragment of the cytochrome c oxidase subunit I (COI) was amplified by PCR from parasite DNA, and analysed by single-strand conformation polymorphism (SSCP) and sequencing. There was no significant variation in SSCP profiles within a morphospecies from a particular host species, but significant variation existed among morphospecies originating from different host species. The same morphospecies was found to occur in 1-3 tissue habitats within one host individual or within different individuals of a particular species of host from the same or different geographical areas, and morphospecies appeared to be relatively host specific at the generic level. The results indicated that the species of Capillaria sensu lato examined, although highly variable in their host and tissue specificity, may exhibit the greatest degree of specificity at the level of host genus.

A fatal case of angiostrongyliasis in an 11-month-old infant.

An 11-month-old boy developed flaccid quadriparesis after two months in Fiji, and was transferred to Australia, where a diagnosis of postinfectious myelitis was made. Despite peripheral blood eosinophilia, eosinophils were not detected in the cerebrospinal fluid, and an infective aetiology was not identified. The patient died of progressive bulbar dysfunction. At autopsy, numerous nematodes, identified as Angiostrongylus cantonensis, were seen in vessels of the lungs, brain and spinal cord, associated with pulmonary abscesses and eosinophilic meningitis. A notable feature was the presence of adult nematodes in the lung.

Haycocknema perplexum n. g., n. sp. (Nematoda: Robertdollfusidae): an intramyofibre parasite in man.

Haycocknema perplexum n. g., n. sp. (Nematoda: Robertdollfusidae) is described from a man in Tasmania, Australia. Adult male and female nematodes and larvae were recovered from myofibres following biopsy of the right vastus lateralis muscle and were associated with a polymyositis. H. perplexum is distinguished from all other genera of the Muspiceoidea by the presence of a large amorphous "cell" supporting a granule-filled, flask- or gourd-shaped reservoir in the rectal region of mature and gravid female nematodes, often containing one or more large, refractile, thick-rimmed "globules" on the external surface of the reservoir, by the small number of ova/eggs/larvae developing in each uterus, by the minute, weakly-sclerotised, almost tubular spicule, by the presence of a pair of ampulla-shaped glands posteriorly and by the presence of lateral bacillary bands comprised of a single row of pore cells spaced irregularly and extending posteriorly to the region of the vulva in immature females.

Crocodylocapillaria longiovata n. gen., n. sp. (Nematoda: Capillariidae) from the stomach of crocodiles in Australia and New Guinea.

A new nematode, Crocodylocapillaria longiovata n. gen. and n. sp., is described from the stomach of wild and farmed young crocodiles, Crocodylus johnstoni Krefft, and Crocodylus porosus Schneider, from northern Australia and Papua New Guinea; it is undoubtedly identical with the nematodes previously reported as Capillaria sp. from Crocodylus novaequineae Schmidt from Irian Jaya, Indonesia. This capillariid species represents a new genus, being characterized mainly by the presence of elongate eggs with unusually long protruding polar plugs, a well developed vulvar appendage, a weakly sclerotized spicule, proximal and distal parts of the spicular sheath with spines, and the male posterior end with 2 large lateral caudal lobes and a pair of papillae near the cloacal opening. The body length of C. longiovara males and females is 5,576-7,208 microm and 8,609-14,008 microm, respectively, the spicule is 276-369 microm long; the size of the egg proper is 48-60 x 15-21 microm, length of polar plugs 15-18 microm. Neocapillaria Yi and Guitang, 1994, a junior homonym of Neocapillaria Moravec, 1987, is re-named Sinocapillaria nom. n. and placed as a synonym of Pseudocapillaria Freitas, 1959. Indocapillaria De and Maity, 1995 is retained as a subgenus of Pseudocapillaria because of the possession of a vulvar appendage in the type species. Neocapillaria Moravec, 1987 remains a subgenus of Capillaria Zeder, 1800. A key to genera of the Capillariidae from poikilotherm vertebrates is provided; C. longiovata is the first capillariid species described from the digestive tract of crocodiles.

Polymyositis caused by a new genus of nematode.

We report two patients who presented with increasing malaise and myalgia, and had biopsy-proven polymyositis. Their conditions deteriorated after corticosteroid treatment, and repeat muscle biopsies showed adult and larval nematodes. Anthelminthic treatment was completely successful in both cases. The infecting nematode appears to belong to a new genus and is, to our knowledge, the first known muspiceoid nematode to infect humans. Its life cycle and the route of infection are unknown.

Endoparasite control strategies: implications for biodiversity of native fauna.

Efforts to control the spectrum of diseases that affect humans, our crops and our animals pose problems which need to be debated openly. Widespread use of chemicals in such a broad sphere raises important concerns not only about safety for the users, consumers and target species, but especially about the not so obvious effects upon the ecosystems in which they are used. Some undetermined level of biological diversity is necessary to maintain ecological function and resilience. These, in turn, are necessary for generating the biological resources (trees, fish, wildlife, crops) and ecological services (watershed protection, air cleansing, climate stabilisation, erosion control) on which economic activity and human welfare depend. The driving forces behind decline of biodiversity stem entirely from human activities. Underlying causes are those resulting from the cultural and social factors associated with economic activities and lead to direct depletion of species, and degradation or destruction of habitats. The broad spectrum and high efficacy of the macrocyclic lactones against nematode and arthropod parasites of livestock and companion animals are unprecedented. Cattle, horses, sheep, swine, dogs--to varying degrees all are utilised by humans for economic gain. Detrimental impact upon non-target animals is considered acceptable in eradicating parasites because of their economic importance to commercial livestock production. Production will increase when these parasites are eliminated, but we remain oblivious to the long-term consequences of our actions. What are the ecological limits to rural economic activities? Decomposing animal faeces help to maintain our ecosystem by returning valuable nutrients to the soil. Dung fauna-fungi, yeast, bacteria, nematodes, insects and earthworms--play a non-conspicuous but important and varied role in this decomposition process, a role dependent upon many factors, especially environmental ones. Anthelmintics and pesticides are of considerable value in agriculture, but largely at an unevaluated cost to the greater environment. We have insufficient knowledge of the extent to which a spectrum of anthelmintics and pesticides affect ecological function and ecosystem resilience in our commercial plant and animal production systems. It is time we developed a genuine interest in avoiding "the dialogue of the deal" that in the past has minimised interdisciplinary research between environmental ecology and commercial plant and animal production.