Hringormar í fólki á Íslandi árin 2004-2020

Abstract

Á árabilinu 2004-2020 voru 18 hringormslirfur (Nematoda) sendar til rannsókna og tegundagreiningar á sníkjudýradeild Tilraunastöðvarinnar að Keldum. Fjórtán lirfanna höfðu lifað tímabundið í fólki og voru lifandi þegar þær fundust, þrjár fundust lifandi í fiski sem fólk var að borða, ein fannst dauð. Pseudoterranova decipiens fannst í 16 tilvikum (89%), Anisakis simplex í tveimur (11%). Annað Anisakis-tilfellið var lirfa sem fannst spriklandi í bleyju barns sem talið var að hefði fengið lirfuna úr vanelduðum fiski á barnaheimili. Í hinu tilvikinu fannst dauð lirfa í soðinni ýsutuggu, sem barn, sem verið var að mata, spýtti út úr sér. Pseudoterranova-lirfur sem lifað höfðu í fólki (n=13) fundust oftast í munni (11 tilvik), í einu tilfelli fann móðir spriklandi lirfu í ælu barns, í öðru fannst hringormur hreyfa sig við endaþarmsop við þrif eftir salernisferð. Lengd lirfanna var 30 mm til 47 mm og voru þær taldar hafa lifað allt frá einum upp í 9 daga í fólkinu. Níu lirfanna höfðu þegar náð að þroskast upp á fjórða stig (L4), fjórar voru enn á þriðja stigi (L3). Þorskur var oftast nefndur sem uppspretta lirfanna (5 tilfelli af 14), tvær manneskjur töldu lirfurnar komnar úr steinbít, einn nefndi báðar þessar tegundir. Sushi eða skarkoli voru álitin uppsprettan í einu tilviki, einn smitaðist í sushi-veislu. Uppruninn var óþekktur í fjórum tilvikum. Oftast töldu menn sig hafa smitast í heimahúsi, þrír álitu sig hafa smitast á veitingastað, sama barn smitaðist tvisvar á barnaheimili og hafnarstarfsmaður smitaðist við að borða hráan fisk.

During 2004-2020 in total 18 anisakid larvae (Nematoda) were sent in to the Laboratory of Parasitology at Keldur for investigation and species identification. Fourteen had temporarily lived within the human body and were alive when detected, three were noticed alive in food just before being consumed, one larva was found dead. Pseudoterranova decipiens was found í 16 instances (89%), Anisakis simplex in two (11%). The one Anisakis case was a wriggling larva detected in the diaper of a baby that was believed to have ingested the larva with undercooked fish three days earlier in the kindergarten. In the other case a dead larva was found entangled in fish chew, spit out by a baby being fed with boiled haddock. Pseudoterranova larvae in humans (n=13) were most frequently detected in the mouth (11 persons). In one instance winding movements of larva in vomit of a baby attracted the attention of the mother, in another case a person detected tickling movements of a larva when cleaning the anal area after defecation. Length of the 13 Pseudoterranova larvae varied between 30 and 47 mm. They were believed to have lived in their hosts from one up to nine days. Nine larvae had already developed to the L4, stage, four were still in the L3 stage. Cod was the most frequently mentioned source of infection (5 of 14 cases), two persons regarded catfish to be the culprit, one named both fish species. In one case either sushi or plaice was believed to be the infection source, one person presumably got the larva participating in a sushi feast. In four cases the fish source remained unknown. Most often the larva was consumed in private homes, three persons believed to have gotten the larva when dining in a restaurant, a harbour worker got the worm when eating raw fish and the same baby got a larva on two different occasions in the kindergarten.