{"id":1067,"date":"2013-02-25T17:49:32","date_gmt":"2013-02-25T07:49:32","guid":{"rendered":"https:\/\/theveterinarian.com.au\/?p=1067"},"modified":"2013-03-01T17:52:41","modified_gmt":"2013-03-01T07:52:41","slug":"wildlife-sentinels-reveal-expanding-distribution-of-rat-lungworm","status":"publish","type":"post","link":"https:\/\/theveterinarian.com.au\/?p=1067","title":{"rendered":"Wildlife sentinels reveal expanding distribution of rat lungworm"},"content":{"rendered":"\"\"<\/a>A study examining the role of wildlife species as sentinels for rat lungworm suggests an expanded distribution of the parasite, and the need for pet owners and wildlife carers to take precautions in order to minimise transmission of the disease to animals in care.<\/span>\r\n\r\nRat lungworm, or Angiostrongylus cantonensis,<\/em> was the most common cause of neurological disease in tawny frogmouths (Podargus strigoides<\/em>) in the Sydney region, and is an emerging disease in brushtail possums (Trichosurus vulpecula<\/em>).<\/span>\r\n\r\nPrevious histological surveys, also conducted in Sydney and published in 1993 and 1995, failed to detect evidence of the parasite in either species.<\/span>\r\n\r\nRat lungworm is known to cause neurological disease in a range of species including dogs, wallabies, foxes and birds, and is the most common cause of eosinophilic meningitis in humans. Adult worms dwell in the pulmonary arteries and right ventricle of rats. Larvae are shed in rat faeces where they are ingested by intermediate hosts \u2013 most notably slugs and snails. They moult twice within the intermediate hosts to the L3 stage which are infectious to rats and other hosts.<\/span>\r\n\r\nOnce ingested, the L3 larvae penetrate the intestinal wall of the host, spreading haematogenously and via the lymphatic system to the brain and spinal cord. Here the combination of migration and associated inflammation causes neurological disease, often characterised by marked pain in people.<\/span>\r\n\r\n\u201cThe parasite originated in south eastern China and has been expanding its range worldwide and within invaded countries since World War II,\u201d Sydney University veterinary pathologist and study co-author Derek Spielman said.<\/span>\r\n\r\n\u201cAs it originated from a tropical to semi-tropical environment and first established in Australia in semi-tropical south eastern Queensland, climate change may be facilitating its range increase.\u201d <\/span>\r\n\r\nBecause the parasite does not rely on the establishment of exotic molluscs for success, it is able to infect a wide range of intermediate hosts.<\/span>\r\n\r\nKey clinical signs of rat lungworm in tawny frogmouths include severe paresis or paralysis of the legs followed by progressive weakness of the wings and subdued mentation.<\/span>\r\n\r\n\u201cFrogmouths that are rescued early in the disease show weak legs so can\u2019t land or stand and can be picked up by members of the public early,\u201d Spielman said. \u201cThese birds tend to have normal mentation (they threaten with wide gapes and vocalisations), good condition (good fat deposits and musculature) and may flap weakly but generally can\u2019t fly and can\u2019t right themselves if placed on their backs. Placing your finger in their claws does not illicit clenching which it normally would.\u201d <\/span>\r\n\r\nSeverely affected birds may be moribund on presentation.<\/span>\r\n\r\nAffected brushtail possums may exhibit hindlimb paresis or paralysis without any indication or history of trauma.<\/span>\r\n\r\n\u201cOther neurological signs are not as indicative as the signs seen in tawny frogmouths as brushtail possums suffer from a number of neurological syndromes that are yet to be resolved aetiologically such as wobbly possum syndrome,\u201d Spielman said.<\/span>\r\n\r\nAccording to Spielman, the current findings have implications for public health, pet owners and anyone involved in the care of native wildlife.<\/span>\r\n\r\n\u201cParents should be alert to the possibility of young children finding and eating snails and slugs (or frogs) in the garden or even pet food left in bowls,\u201d he said. \u201cAbout two children per year in Sydney are affected [by rat lungworm] and occasionally this results in significant brain damage or death.\u201d<\/span>\r\n\r\nFruit and vegetables from gardens frequented by snails and slugs should be washed thoroughly before consumption. Spielman said this is particularly important with back garden and organically grown produce where molluscicides are not used.<\/span>\r\n\r\nDog and cat food bowls should not be left out where they can be exposed to snails or slugs.<\/span>\r\n\r\n\u201cEating slugs in food bowls is a common way puppies are infected,\u201d Spielman said.<\/span>\r\n\r\n\u201cCarers must be careful not to feed contaminated fruit or vegetables to possums or any other animal in care which means washing all produce thoroughly and not leaving food in bowls overnight outside when snails and slugs are active,\u201d he said.<\/span>\r\n\r\nWhile this is contrary to the natural nocturnal feeding behaviour of these species, it is an important means of preventing disease transmission.<\/span>\r\n\r\n\u201cPerhaps removing the food bowls before you go to sleep will give them time to eat before the food is removed.<\/span>\r\n\r\nSymptomatic treatment is often successful in people and dogs where the disease is picked up early, but the prognosis for affected wildlife species is grave.<\/span>\r\n\r\n\u201cWildlife invariably are severely affected with permanent neurological damage by the time they come in to care,\u201d Spielman said. \u201cThis means even if they don\u2019t die they will not be able to survive in the wild so are euthanised.\u201d<\/span>\r\n\r\nControl of definitive hosts (the introduced black rat, Rattus rattus<\/em>, and the Norway rat, Rattus norwegicus<\/em>) reduces the risks of angiostrongylosis.<\/span>\r\n\r\nThe research team plans to expand their study to investigating the prevalence of rat lungworm in wild rats, slugs and snails. In the near future, they will be calling veterinarians and members of the public to submit snails and slugs to determine whether the parasite is present.<\/span>\r\n\r\nAnne Fawcett<\/span><\/strong>\r\n\r\nReference<\/strong><\/span>\r\n\r\nMa G, Dennis M, Rose K, Spratt D and Spielman D (2013) Tawny frogmouths and brushtail possums as sentinels for Angiostrongylus cantonensis<\/em>, the rat lungworm. Veterinary Parasitology<\/em> 192:158-165.<\/span>","protected":false},"excerpt":{"rendered":"

A study examining the role of wildlife species as sentinels for rat lungworm suggests an expanded distribution of the parasite, and the need for pet owners and wildlife carers to take precautions in order to minimise transmission of the disease to animals in care. Rat lungworm, or Angiostrongylus cantonensis, was the most common cause of […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[920,30,405,97,922,918,923,919,921],"class_list":["post-1067","post","type-post","status-publish","format-standard","hentry","category-news","tag-angiostrongylus-cantonensis","tag-anne-fawcett","tag-birds","tag-disease","tag-infections","tag-lungworm","tag-neurology","tag-rat-lungworm","tag-tawny-frogmouth"],"rise-blocks_total_comments":0,"rise-blocks_categories":[{"term_id":5,"name":"News","slug":"news","term_group":0,"term_taxonomy_id":5,"taxonomy":"category","description":"","parent":0,"count":403,"filter":"raw","cat_ID":5,"category_count":403,"category_description":"","cat_name":"News","category_nicename":"news","category_parent":0}],"rise-blocks_excerpt":"A study examining the role of wildlife species as sentinels for rat lungworm suggests an expanded distribution of the parasite, and the need for pet owners and wildlife carers to take precautions in order to minimise transmission of the disease to animals in care. Rat lungworm, or Angiostrongylus cantonensis, was the most common cause of neurological disease in tawny frogmouths..","blog_post_layout_featured_media_urls":{"thumbnail":"","full":""},"categories_names":{"5":{"name":"News","link":"https:\/\/theveterinarian.com.au\/?cat=5"}},"tags_names":{"920":{"name":"Angiostrongylus cantonensis","link":"https:\/\/theveterinarian.com.au\/?tag=angiostrongylus-cantonensis"},"30":{"name":"Anne Fawcett","link":"https:\/\/theveterinarian.com.au\/?tag=anne-fawcett"},"405":{"name":"birds","link":"https:\/\/theveterinarian.com.au\/?tag=birds"},"97":{"name":"disease","link":"https:\/\/theveterinarian.com.au\/?tag=disease"},"922":{"name":"infections","link":"https:\/\/theveterinarian.com.au\/?tag=infections"},"918":{"name":"lungworm","link":"https:\/\/theveterinarian.com.au\/?tag=lungworm"},"923":{"name":"neurology","link":"https:\/\/theveterinarian.com.au\/?tag=neurology"},"919":{"name":"rat lungworm","link":"https:\/\/theveterinarian.com.au\/?tag=rat-lungworm"},"921":{"name":"tawny frogmouth","link":"https:\/\/theveterinarian.com.au\/?tag=tawny-frogmouth"}},"comments_number":"0","wpmagazine_modules_lite_featured_media_urls":{"thumbnail":"","cvmm-medium":"","cvmm-medium-plus":"","cvmm-portrait":"","cvmm-medium-square":"","cvmm-large":"","cvmm-small":"","full":""},"_links":{"self":[{"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=\/wp\/v2\/posts\/1067","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1067"}],"version-history":[{"count":2,"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=\/wp\/v2\/posts\/1067\/revisions"}],"predecessor-version":[{"id":1070,"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=\/wp\/v2\/posts\/1067\/revisions\/1070"}],"wp:attachment":[{"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1067"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1067"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/theveterinarian.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1067"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}