Angiostrongylus cantonensis Nematode Invasion Pathway, Mallorca, Spain

Abstract

T he rat lungworm, Angiostrongylus cantonensis, infects animals and humans. Although this nematode species is recognized as the main etiologic agent of eosinophilic meningitis (1), infection might result in other central nervous system disorders (2). Clinical manifestations are aggravated by movement and subsequent death of the worms in the central nervous system, causing physical lesions and inflammation in accidental hosts (3). In humans, severe headache, neck stiffness, paresthesia, convulsions, urinary failure, visual impairment, and other symptoms, occasionally leading to coma and death, have been reported (1,4).The life cycle of A. cantonensis worms includes rats as definitive and gastropods as intermediate hosts; crustaceans, planarians, amphibians, reptiles, and fish might act as paratenic hosts (2). More than 20 vertebrate species, including humans, have been reported as A. cantonensis lungworm accidental hosts (5). This long list of vertebrate hosts includes nonhuman primates (6), marsupials (7), bats (8), horses (9), dogs (10), birds (11), and more recently, hedgehogs (12). The role of hedgehogs in the transmission of this parasite remains to be clarified.A. cantonensis worms were detected in Canton, China, infecting the lungs of rats ( 13) and a decade later, in the cerebrospinal fluid of a person from Taiwan (14). For decades, disease-endemic areas were limited to the Pacific basin and Southeast Asia, but this parasite has spread to new territories at an alarming rate (1). The invasion of A. cantonensis lungworms has been associated with unintended importation of infected rats and gastropods on ships (2,15). Almost 3,000 cases of human neuroangiostrongyliasis have been reported (16) from 30 territories (3), although the prevalence might be higher (17).Europe was considered to be nonendemic for A. cantonensis worms until 2018 when the parasite was reported infecting the brains of 2 hedgehogs on the Mediterranean island of Mallorca (12). Although the rat lungworm had been previously reported on Tenerife, a subtropical, non-European overseas oceanic island (18), its detection in Mallorca is an indisputable indication of its presence in Europe (5). Mallorca is a major Mediterranean tourism hotspot, highly interconnected with continental Europe. After the detection, the question remained whether A. cantonensis nematodes could survive the temperate winters of Europe. The purpose of this study was to use sentinel surveillance for symptomatic fauna to confirm whether the rat lungworm has been successfully established on Mallorca.

Neuroangiostrongyliasis: Global Spread of an Emerging Tropical Disease

“…The global distribution, by country, of combined reported presence of Angiostrongylus cantonensis and cases of human or animal neuroangiostrongyliasis (red circles), with cases in returning travelers to nonendemic areas distinguished (blue circles). 2,[4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] If part of a country is distant from the main part of the country-Guam, Saipan, Hawaii, American Samoa, and Puerto Rico (United States); Ryukyu and Ogasawara Islands (Japan); New Caledonia, Tahiti, Mayotte, R eunion, Guadeloupe, and Martinique (France); and Canary Islands and Mallorca (Spain)-dots are placed on those locations in addition to the main part of country (if also present there). For most countries/territories, a single dot has been placed roughly where the greatest concentration of records occurs.…”

Paratenic hosts of Angiostrongylus cantonensis and their relation to human neuroangiostrongyliasis globally

“… Host Location Confirmed or assumed References Freshwater prawns/shrimp Macrobrachium australe Tahiti Naturally Primary: [ 56 ] Secondary: [ 23 , 53 ] Macrobrachium lar French Polynesia, American Samoa Naturally and experimentally Primary: [ [56] , [57] , [58] ] Secondary: [ 20 , 23 , 53 , [59] , [60] , [61] , [62] , [63] , [64] , [65] ] Macrobrachium spp. French Polynesia, Pohnpei, Saipan, Guam, Rarotonga, Dominican Republic Naturally and experimentally Primary: [ 15 , 66 , 67 ] Secondary: [ [2] , [3] , [4] , [5] , [6] , [7] , [8] , [11] , [12] , [17] , [19] , [23] , [41] , [45] , [47] , [51] , [53] , [62] , [65] , [67] , [68] , [69] , …”

“…Not only are clinical cases of neuroangiostrongyliasis steadily increasing [ 86 ], but recent studies have recorded A. cantonensis in areas where it was previously unknown [ 3 , 41 , 42 , 45 , 46 , 152 ]. This spread is facilitated by increasing globalisation leading to the further introduction of infected rats and other invasive host species, e.g.…”

“…Cases of neuroangiostrongyliasis have occurred further afield, in Australia, the USA and the Caribbean (initially Cuba) since the 1970s and perhaps earlier [ 3 , 7 , 11 , [36] , [37] , [38] ]. More recently, A. cantonensis has been recorded in other areas, including additional Caribbean islands [ 20 , 39 , 40 ], Mallorca [ 41 ] and the Canary Islands [ 42 ]. It is now widely distributed across many tropical/subtropical regions globally [ 3 , 13 , 43 ], as well as a few more temperate localities [ [44] , [45] , [46] ].…”

Angie-LAMP for diagnosis of human eosinophilic meningitis using dog as proxy: A LAMP assay forAngiostrongylus cantonensisDNA in cerebrospinal fluid

“…The 'rat lungworm' (Angiostrongylus cantonensis) is a nematode with a unique affinity for the central nervous system (CNS) found throughout the Asia-Pacific region, and more recently in the United States and Europe [1][2][3][4][5][6][7][8]. Currently, A. cantonensis is recognised globally as the leading cause of eosinophilic meningitis in humans, which is a serious condition observed when larvae migrate to the CNS [5,9,10].…”