Rhinonyssids are obligate haematophagous mites that parasitize the nasal cavity of vertebrates, and occur in a wide range of birds worldwide. Two species of nasal mites are known to occur in ...penguins: Rhinonyssus sphenisci, which has been recorded from Humboldt and Magellanic penguins (Spheniscus humboldti and S. magellanicus, respectively), and Rhinonyssus schelli, which has been recorded in Adélie and Gentoo penguins (Pygoscelis adeliae and P. papua, respectively). We examined the nasal cavity of African penguins (Spheniscus demersus) that died while under care at a rehabilitation centre (N = 40) or that were found dead at breeding colonies (N = 67). Nasal mites were found in the nasal cavity and/or paranasal of sinuses of 21 penguins, some of which had signs of mild-to-moderate sinusitis. Prevalence was higher in juveniles (29%) and adults (27%) than in chicks (10%). Mean intensity was 5.9 ± 12.9 mites per infected host (range 1-60). The mites presented morphological characteristics that were at times consistent with either R. sphenisci or R. schelli, and therefore we conservatively classified them as 'R. sphenisci sensu lato'. Our morphometric results raise the question of whether the specific status of R. schelli is justified.
Recent advances on ocular Demodex infestation Cheng, Anny M.S; Sheha, Hosam; Tseng, Scheffer C.G
Current opinion in ophthalmology,
2015-July, 2015-Jul, 20150701, Volume:
26, Issue:
4
Journal Article
PURPOSE OF REVIEWTo summarize recent advances on ocular Demodex infestation.
RECENT FINDINGSDemodex infestation is a potential cause of ocular surface inflammation. The pathogenesis of Demodex in ...eliciting ocular surface inflammation has been further clarified. Cliradex is currently the treatment of choice, it comprises the most active ingredient of tea tree oil, that is terpinen-4-ol, which helps eradicate Demodex mites and reduce ocular surface inflammation.
SUMMARYOcular demodicosis is a common but overlooked eye disease that manifests a number of morbidities. Demodex folliculorum causes chronic anterior blepharitis whereas Demodex brevis causes posterior blepharitis, meibomian gland dysfunction, recurrent chalazia, and refractory keratoconjunctivitis. The lash sampling and microscopic counting method and in-vivo confocal microscopy are key diagnostic methods. Cliradex shows promising potential to reduce Demodex counts with additional antibacterial, antifungal, and anti-inflammatory actions.
Quill mites belonging to the subfamily Syringophilinae Lavoipierre, 1953 associated with the Nearctic passeriform birds are revised. All of the 49 known species, which are grouped in seven genera, ...are recorded. Among them, four new species are described: Syringophiloidus audubioni sp. nov. from Spizella breweri (Cassini) (Emberizidae), Syringophilopsis catesbyi sp. nov. from Vireo olivaceus (Linnaeus) (Vireonidae), S. wilsoni sp. nov. from Pheucticus melanocephalus (Swainson) (Cardinalidae), and S. bartrami sp. nov. from Spizella passerina (Bechstein) (Emberizidae). The species Syringophilopsis hylocichlae Clark, 1964 syn. nov. is synonymized with Syringophilopsis turdus (Fritsch, 1958), and Syringophiloidus zonotrichia syn. nov. is synonymized with Betasyringophiloidus seiuri (Clark, 1964) comb. nov. Six species are recorded from the Nearctic region for the first time: Syringophiloidus delichonum Bochkov, 2001, S. glandarii (Fritsch, 1958), S. weiszii Skoracki et al., 2001, S. bombycillae Skoracki, 2002, Syringophilopsis mimidus Sikora et al., 2011, and Torotrogla merulae Skoracki et al., 2000. Data on Nearctic syringophiline species, their hosts and distribution are summarized and the keys to all species are constructed.
Ornithonyssus bacoti, commonly known as the tropical rat mite, is a zoonotic ectoparasite that occasionally infests research rodent colonies. Most infestations have been attributed to wild rodents ...that harbor the mite and spread it to research animals, often during building construction or other activity that disrupts wild rodent populations. Although infestation may be clinically silent, severe outbreaks have been reported to cause pruritis, dermatitis, decreased reproductive performance, and anemia in rodents. In mid 2020, our institution experienced increased activity of wild mice, which were found to be infested with O. bacoti, diagnosed by microscopic exam and confirmed by fur swab PCR analysis. We elected to add O. bacoti to our quarterly health monitoring exhaust air dust (EAD) testing PCR panel, increase wild mouse control measures, and treat the environment with a sustained-release synthetic pyrethroid spray in an attempt to prevent colony animal infestation. Initial quarterly EAD health monitoring results in September of 2020 were negative for O. bacoti. However, in early 2021, multiple IVC racks tested positive for O. bacoti at quarterly testing. Treatment consisted of providing permethrin soaked nesting material and surface spray treatment of the room and hallway with a sustained-release synthetic pyrethroid. Historically in the literature, O. bacoti outbreaks of research mice were not identified until mite burden was high enough to cause dermatitis on animal care workers. Due to modern molecular diagnostics and proactive PCR-based health monitoring surveillance, we were able to identify the outbreak earlier than would have otherwise been possible. To the best of our knowledge, this is the first report to successfully identify O. bacoti using environmental health monitoring PCR techniques. This outbreak demonstrates the importance of screening for O. bacoti in facilities with the potential for wild rodent infestation and highlights unique considerations when managing O. bacoti infestations. In addition, a novel permethrin-soaked enrichment item was developed for cage-level treatment.
We studied patterns of compositional, functional, and phylogenetic α- and β-diversity in flea and gamasid mite infracommunities of small Siberian mammals, taking into account host-associated ...(species) and environmental (biome or sampling period) factors. We asked: (a) How do these factors and their interactions affect infracommunity diversity? (b) Does infracommunity composition, in terms of species, traits, and phylogenetic lineages, deviate from random? (c) Are species, traits, and phylogenetic lineages in infracommunities clustered or overdispersed?, and (d) Do patterns of diversity differ between the three diversity facets and/or the two ectoparasite taxa? We found that the α-diversity of infracommunities was strongly affected by host species, biome, and sampling period. The highest proportion of infracommunity diversity in both taxa was associated with the interaction between either host species and biome or host species and sampling period. Infracommunities of both taxa within, as well as between, host species, biomes, and sampling periods were characterized by the clustering of species, traits and lineages. The patterns of the effects of host species, biome, and sampling period on infracommunity diversity were congruent among the three diversity facets in both fleas and mites. We conclude that the assembly patterns in ectoparasite infracommunities mirror those characteristics of component and compound communities.
Brevipalpus phoenicis sensu stricto (Geijskes) is redescribed and the species diagnosis established. Two former synonyms of B. phoenicis sensu lato, B. yothersi Baker and B. papayensis Baker, are ...resurrected and redescribed and their species diagnoses established. Brevipalpus hondurani Evans is also redescribed and diagnosed. Four new species, previously misidentified as B. phoenicis sensu lato or B. obovatus Donnadieu, are described--B. azores sp. nov., B. feresi sp. nov., B. ferraguti sp. nov., and B. tucuman sp. nov. Four new junior synonyms of B. yothersi are listed--Brevipalpus amicus Chaudhri and B. recula Chaudhri (new synonymies), and B. mcbridei Baker and B. deleoni Pritchard and Baker (misidentifications). A key is provided to separate these species. New morphological characters significant for species separation are presented and discussed.
Demodex mollis n. sp. is described from the yellow-necked mouse, Apodemus flavicollis (Melchior, 1834), from Poland. It is a medium-sized demodecid mite (adult stages are, on average, 249 μm long) ...observed in the skin of the eyelid area. This new species is most similar to two other species occupying similar a microhabitat in hosts of the same genus—Demodex lacrimalisLukoschus and Jongman, 1974 from Apodemus sylvaticus Linnaeus, 1758 and Demodex huttereriMertens, Lukoschus and Nutting, 1983 from Apodemus agrarius (Pallas, 1771)—but it differs in the following features: the terminal palpi are equipped with 3 spines, including 1 large claw-like spine and 1 single spine; subgnathosomal setae (setae n) are situated on both sides of the anterior side of the pharyngeal bulb; claws on the leg tarsi are bifurcated and each is equipped with large subterminal spur and proximal pointed projection; the opisthosoma is soft and flexible; and the male aedeagus has a different shape and localization. The differences also relate to sexual dimorphism. Males are more robust and stocky, epimeral plates I and IV are connected at the midline part of the podosoma, and epimeral plates II and III are separated. Females are slender, epimeral plates I–III are connected at the midline of the podosoma, and epimeral plate IV ia fused in 1 plate. The new species was noted in 22.5% of mice, with a mean intensity of 7.0 parasites per host. The topography of demodecid mites was also analyzed in the skin of A. flavicollis, and also Demodex corniculatusIzdebska, 2012 was observed in the hairy skin of the bodies of all the examined mice.
Background
Human Demodex mites, Demodex folliculorum and Demodex brevis, are microorganisms that reside in the pilosebaceous units, usually without causing symptoms. Phototherapy has been linked to ...demodicosis in previous studies. We aimed to determine whether there was an increase in the frequency of demodicosis and Demodex density after 20 phototherapy sessions.
Methods
A case–control study was conducted with 32 participants who received narrowband ultraviolet B or ultraviolet A‐1 therapy for various dermatological indications. Standardized skin surface biopsies were performed before and after phototherapy to assess Demodex density. The presence of Demodex‐related skin conditions was assessed before phototherapy. A statistical analysis was performed to compare the Demodex densities and prevalence of demodicosis between the baseline and 20th session of phototherapy.
Results
No significant change was observed in Demodex density after 20 sessions of phototherapy. The average Demodex density before treatment was 2.75 ± 4.48 (/cm2), and after treatment, it was 2.85 ± 4.81 (/cm2), indicating no significant difference (P = 0.879). The percentage of patients with demodicosis in at least one region of the face was 28.1% (9/32) before treatment, and after treatment, it was 31.3% (10/32), with no significant difference (P = 1.00).
Conclusions
Our findings contradict previous studies that suggested an increased Demodex density and demodicosis prevalence after phototherapy. The data from previous studies are open to debate due to their selected samples, designs, and interpretations regarding the phototherapy–immunosuppression–Demodex relationship. Larger‐scale longitudinal studies conducted on a homogeneous sample are warranted to better understand the relationship between phototherapy and demodicosis.
