Urban emergence of Dermanyssus gallinae lineage L1 and Ornithonyssus sylviarum in Hungary: phylogenetic differentiation between the roles of migrating vs transported synanthropic birds

Background: Among Dermanyssoidea, the chicken red mite (Dermanyssus gallinae) and the northern fowl mite (Omithonyssus sylviarum) are considered to be the cause of high economic losses endured by the poultry industry in the Holarctic region, with O. sylviarum predominating in North America and D. gallinae in Europe. Both species have a short life-cycle (thereby allowing a rapid build-up of massive infestations), a wide range of hosts, synanthropic presence and the ability to bite humans. The aim of this study was to analyze dermanyssoid mite specimens, collected in two human dwellings and two racing pigeon premises in different urban areas in Hungary, with molecular-phylogenetic methods. Methods: Mite species were identified morphologically. This was followed by DNA extraction and molecular-phylogenetic analyses of selected mites, based on the cytochrome c oxidase subunit I (cox1) and 28S rRNA (28S) genes. Results: Mites that had invaded a home from a pigeon nest and were linked to human dermatitis were morphologically and molecularly identified as D. gallinae special lineage la Specimens collected at all other sampling sites were identified as O. sylviarum, including mites that had invaded a home from a house martin (Delichon urbicum) nest, as well as those which were collected from racing pigeons. House martin- or pigeon-associated O. sylviarum specimens showed the highest sequence identity and closest phylogenetic relationship with conspecific mites reported in GenBank from Israel or Canada, respectively. Conclusions: Detailed morphological and molecular-phylogenetic analyses of D. gallinae lineage L1 confirmed its status as a cryptic species within D. gallinae (s.I.). Taking into account the well-documented latitudinal migratory routes of house martins between Hungary and Africa, O. sylviarum associated with this bird species most likely arrived on its host from the eastern Mediterranean region. On the other hand, mites collected from pigeons in Hungary showed cox1 genetic homogeneity with North American O. sylviarum, which can only be explained by a long-distance (west-to-east intercontinental) connection of birds and their mites as part of human activity (e.g. transportation to exhibitions or trading). In summary, this is the first molecularly confirmed and phylogenetically analyzed case of O. sylviarum infestation of birds in Hungary, implicating urban environment and involving distant parts of the country. This is also the first report of D. gallinae lineage L1 in central Europe.

Automated summary

This study analyzed Dermanyssoid mite specimens collected from two human dwellings and two racing pigeon premises in different urban areas in Hungary using molecular-phylogenetic methods. The results identified D. gallinae in a home invaded from a pigeon nest and linked to human dermatitis, while O. sylviarum was found at all other sampling sites, showing a close phylogenetic relationship with conspecific mites reported in other countries. The study also confirmed the first molecularly analyzed case of O. sylviarum infestation of birds in Hungary and the first report of D. gallinae lineage L1 in central Europe.