Cercopithifilaria Bainae Research Articles

Cercopithifilaria spp. in ticks of companion animals from Asia: new putative hosts and vectors

Cercopithifilaria bainae, Cercopithifilaria grassi, and Cercopithifilaria sp. II sensu Otranto et al., 2013 tick borne filarioids are typically found in dogs. Among them, Cercopithifilaria bainae has a worldwide distribution according to the occurrence of its tick vector, Rhipicephalus sanguineus sensu lato (s.l.). Nevertheless, in Asian countries, despite the wide presence of this tick species, data on Cercopithifilaria spp. are scant. Therefore, this study aimed to assess the occurrence of these dermal filarioids in ixodid ticks collected on dogs and cats from Asian countries, providing a better epidemiological picture on their distribution in this continent. Ticks (n = 687) of the species Rhipicephalus sanguineus s. l. (n = 667), Rhipicephalus haemaphysaloides (n = 8), Haemaphysalis longicornis (n = 7), Haemaphysalis campanulata (n = 1), Haemaphysalis wellingtoni (n = 2), Haemaphysalis hystricis (n = 1), and Ixodes sp. (n = 1) were collected on dogs and cats under the frame of previous studies in China, India, Indonesia, Malaysia, Singapore, Taiwan, Thailand, the Philippines and Vietnam. Tick samples were molecularly screened for Cercopithifilaria spp. by conventional PCR and real-time PCR using two pair of primers targeting partial sequences of cytochrome c oxidase 1 gene. Overall, Cercophitifilaria spp. DNA was detected in 9.5% (n = 65/687) of the tick specimens tested, with C. bainae being the most prevalent species (8.9%), followed by C. grassii (0.6%). Most Cercophitifilaria spp. positive ticks were collected on dogs (92.3%; 60/65); whereas ticks collected on cats represented 7.7% of the positive specimens. In addition, Cercopithifilaria spp. were mostly detected in R. sanguineus s.l. ticks (96.9%; 63/65), followed by Rhipicephalus haemaphysaloides (3.1%; 2/65). Data herein presented demonstrate the occurrence of dermal tick borne filarioids of the genus Cercopithifilaria in several Asian countries, with C. bainae being the most prevalent species. We also report for the first time the molecular detection of C. bainae in R. sanguineus s.l. ticks collected on cats, as well as in R. haemaphysaloides ticks, suggesting that the biological cycle of this filarioid species may involve other intermediate and definitive hosts than R. sanguineus s.l. and dogs. However, confirmatory studies on the role of other tick species and domestic cats on the biology of C. bainae are advocated.

Molecular detection of Cercopithifilaria bainae in brown dog ticks collected from dogs across the United States

Cercopithifilaria bainae is a filarioid nematode of dogs shown to use Rhipicephalus sanguineus sensu lato (s.l.), the brown dog tick, as the vector. Previously in the United States, C. bainae infections have been reported in a dog from Florida, and in dogs and ticks in Oklahoma, but data are lacking from other areas of the country. Here, we tested brown dog ticks from across the United States for C. bainae DNA to assess the geographic distribution of where this novel parasite may be cycling in ticks and dogs. Archival brown dog ticks were available for testing through the national tick survey Show Us Your Ticks. Ticks were morphologically identified, dissected, and tested by PCR to detect filarioid mitochondrial DNA. A total of 1400 brown dog ticks were tested from 321 separate animals from 23 states, with 5.7 % (80/1400) of the ticks testing positive for C. bainae DNA. At least one positive tick was detected in submissions from 9 states in addition to Florida and Oklahoma. Cercopithifilaria bainae DNA was detected in larval, nymphal, and adult stages of brown dog ticks and only in ticks removed from dogs. Of all dogs with brown dog ticks collected from them, 17.6 % (55/312) were infested with at least one tick that harbored C. bainae DNA. Findings from this study demonstrate a wider geographic range of C. bainae than previously known, and that dogs are commonly infested with brown dog ticks with molecular evidence of C. bainae infection.

Major antigen and paramyosin proteins as candidate biomarkers for serodiagnosis of canine infection by zoonotic Onchocerca lupi.

Onchocerca lupi (Spirurida: Onchocercidae) is a filarial worm parasitizing domestic carnivores and humans. Adult nematodes usually localize beneath in the sclera or in the ocular retrobulbar of infected animals, whilst microfilariae are found in the skin. Therefore, diagnosis of O. lupi is achieved by microscopic and/or molecular detection of microfilariae from skin biopsy and/or surgical removal of adults from ocular tissues of infected hosts. An urgent non-invasive diagnostic tool for the diagnosis of O. lupi in dog is mandatory. In this study, an immunoproteomic analyses was performed using a combination of immunoblotting and mass spectrometry techniques. Onchocerca lupi major antigen (Ol-MJA) and paramyosin (Ol-PARA) proteins were identified as potential biomarkers for serodiagnosis. Linear epitopes were herein scanned for both proteins using high-density peptide microarray. Sera collected from dog infected with O. lupi and healthy animal controls led to the identification of 11 immunodominant antigenic peptides (n = 7 for Ol-MJA; n = 4 for Ol-PARA). These peptides were validated using sera of dogs uniquely infected with the most important filarioids infesting dogs either zoonotic (Dirofilaria repens, Dirofilaria immitis) or not (Acanthocheilonema reconditum and Cercopithifilaria bainae). Overall, six antigenic peptides, three for Ol-MJA and for Ol-PARA, respectively, were selected as potential antigens for the serological detection of canine O. lupi infection. The molecular and proteomic dataset herein reported should provide a useful resource for studies on O. lupi toward supporting the development of new interventions (drugs, vaccines and diagnostics) against canine onchocercosis.

Cercopithifilaria species in dogs and ticks from Greece.

Filarioids of the genus Cercopithifilaria (Spirurida, Onchocercidae) are parasites of wild and domestic animals in tropical and subtropical regions being transmitted by ixodid ticks. Though this filarioid species have been studied in canine and tick populations in Europe, data on their species diversity and geographical distribution in Greece is scant. Thus, the aims of this study were to investigate the presence of Cercopithifilaria spp. in dogs and ticks across Greece and to assess the possible risk factors. A total of 500 skin biopsies were collected from dogs, while 508 ticks were collected from 180 infested animals and examined. Sediments from skin biopsies were microscopically screened for detection of dermal microfilaria (mfs). Skin samples (n = 115) and tick specimens (n = 153) were molecularly subjected by PCR. Overall, 70 samples (14%) scored positive for mfs. Specifically, 68 samples (13.6%) were positive for Cercopithifilaria bainae and two (0.4%) were co-infected with C. bainae and Cercopithifilaria sp. II. Molecular analyses revealed that all sequences obtained belong to C. bainae. Haplotype I was the most frequent (92.6%), followed by haplotype XVIII (3%) and haplotypes II and IX (1.5%). Three new haplotypes of C. bainae, named XIX, XX, and XXI, were also identified. Among the risk factors examined, habitat, dog use, body weight, tick infestation history, and the use of acaricides were associated with the presence of C. bainae. The estimated prevalence of Cercopithifilaria spp. demonstrates that these filarioids are common in dogs and ticks in Greece. Finally, the identification of 7 haplotypes for C. bainae confirms their genetic variability.

Detection of Canine Vector-Borne Filariasis and Their Wolbachia Endosymbionts in French Guiana.

In French Guiana, canine heartworm disease is well known, but the diversity of filarial parasites of dogs remains largely unknown. A total of 98 canine blood samples from Cayenne and Kourou were assessed by a blood wet mount preparation, heartworm antigen test and molecular exploration of filarioid and Wolbachia DNAs, followed by a multiplex species-specific qPCR’s identification and a subsequent sequencing analysis. Thereafter, a phylogeny based on maximum likelihood was carried out to facilitate specific identification. Five dogs were microfilaremic. Heartworm antigens were detected in 15 (15.3%) dogs. Of these, six (6.1%) were considered as occult infections as neither microfilariae nor Dirofilaria immitis DNA were detected. The 11 (11.2%) D. immitis isolates corresponded to a low virulent strain. Six of the D. immitis isolates were positive for Wolbachia endosymbionts of D. immitis belonging to the clade C DNA. Acanthocheilonema reconditum DNA was detected in 3 (3.1%) samples. Of these latter, one was found co-infected with the Brugia sp. genotype and the DNA of the clade D of the Wolbachia endosymbiont of Brugia species. This latter was also detected in two filarioid DNA-free samples. Finally, two samples were positive for Cercopithifilaria bainae genotype, which is distinct from those identified in Europe. The present study highlights the urgent need to implement chemoprophylaxis associated with anti-Wolbachia drugs to control these potential zoonoses.

Microfilaremia by Cercopithifilaria bainae in a dog from the central western region of Brazil: case report

ABSTRACT Cercopithifilaria bainae is a nematode belonging to the family Onchocercidae that parasitizes the subcutaneous tissue of dogs. Its transmission occurs through the tick Rhipicephalus sanguineus and its geographical distribution overlaps that of this vector. The present study reports the detection of microfilaremia by C. bainae in an eight-year-old male dog that presented anorexia, hyperthermia, motor incoordination, mydriasis, a nodule in the left testicle and concomitant infection by Ehrlichia sp. Blood samples were analyzed using microscopy, PCR and DNA sequencing. Microfilariae measuring 150±5.5μm in length and 7±1.8μm in width were retrieved. The DNA sequence exhibited 98% identity with C. bainae sequences available in Genbank. This is the first report of microfilaremia by C. bainae in a dog in the central western region of Brazil.

Vector-borne nematode diseases in pets and humans in the Mediterranean Basin: An update.

Vector-borne diseases (VBDs) are among the leading causes of morbidity and mortality in humans and animals. The scale of VBDs is increasing worldwide, including in the Mediterranean Basin, a region exposed to climate changes. Indeed, weather conditions may influence the abundance and distribution of vectors. The vector-borne nematode diseases of dogs and cats, such as dirofilariosis, onchocercosis, thelaziosis, Cercopithifilaria, and Acanthocheilonema infections, are some of these vectorized diseases, several of which are zoonoses. They are all caused by parasitic nematodes transmitted by arthropods, including mosquitoes (Dirofilaria spp.), black flies (Onchocerca lupi), drosophilids (Thelazia callipaeda), ticks (Acanthocheilonema dracunculoides and Cercopithifilaria bainae), and fleas and lice (Acanthocheilonema reconditum). The control and prevention of these infections and diseases require a multidisciplinary approach based on strengthening collaboration between the different actors in the fields of health, research, sociology, economics, governments and citizens, to improve human, animal, and ecosystem health. This is the concept of “one health.” The review aimed to provide a general update on the spatial and temporal distribution of vector-borne nematodes diseases affecting companion animals and humans, as well as the vectors involved in the Mediterranean area. Simultaneously, certain epidemiological parameters, diagnosis, treatment, and control of these diseases based on the “one health” concept will also be discussed.

Dermatitis caused by autochthonous Cercopithifilaria bainae from a dog in Florida, USA: clinical, histological and parasitological diagnosis and treatment

Cercopithifilaria bainae is a tick-vectored filarioid nematode associated with erythematous dermatitis in dogs. It has not been reported previously in the United States. To describe clinical, histological and parasitological diagnosis and treatment of C.bainae in a dog. An 11-month-old golden retriever/standard poodle mixed breed dog from Florida (USA). The dog had no travel history within or outside the United States, was presented with a one month history of annular erythematous plaques on the head and ulcers on the medial canthi. Lesions were unresponsive to antibiotic treatment. Histopathological evaluation of skin biopsies revealed an eosinophilic to lymphohistiocytic perivascular dermatitis with multiple microgranulomas and rare 5-10μm diameter microfilariae within microgranulomas. Microfilarial morphology was consistent with C.bainae. PCR and sequencing of 18S rRNA and mitochondrial cytochrome oxidase subunit I genes confirmed the nematodes as C.bainae. The dog was treated with a commercial spot-on containing imidacloprid and moxidectin, and clinical resolution occurred. To the best of the authors' knowledge, this is the first report of C.bainae in a dog in the United States and the first description of dermatological lesions caused primarily by C.bainae.

Detection of Cercopithifilaria bainae in western Romania.

Cercopithifilaria species are tick-transmitted filarial parasites of mammals. In Europe, three Cercopithifilaria spp. are known to parasitize dogs, all occurring mainly in the Mediterranean countries. In Romania, Cercopithifilaria bainae has been reported in a single dog in eastern Romania but the occurrence in other parts of the country is not known. To further elucidate the geographic distribution of Cercopithifilaria spp. infection, 544 ticks were collected from dogs in several locations across Romania. The presence of Cercopithifilaria spp. was investigated with real-time PCR. A single Dermacentor reticulatus female tick was found to be infected with Cercopithifilaria bainae. The finding in the present study is geographically separated from the previous finding in Romania by 800km, as well as by the Carpathian mountain range. Hence, C. bainae is more geographically widespread in Romania than previously recognized. However, the single detection does suggest that infection is rather uncommon in Romanian dogs. Nevertheless, further studies on Cercopithifilaria spp. distribution and prevalence are needed.

Ticks and associated pathogens in dogs from Greece

With the aim to assess the occurrence of hard ticks and the pathogens they may carry in dogs from Greece, ixodid specimens (n = 757) were collected from 310 animals living in six provinces across the Greek peninsula. All ticks were morphologically identified, and genomic DNA was extracted from 344 (45.5%) representative specimens, according to their species, engorgement status and sampling area. The occurrence of Anaplasma spp., Ehrlichia spp., Hepatozoon spp., Rickettsia spp., Babesia spp., Theileria spp. and Cercopithifilaria spp. was assessed by conventional and quantitative real-time PCR. Overall, 150 dogs (48.4%) were infested by ticks, with Rhipicephalus sanguineus (sensu lato) being the most prevalent (70.1%), followed by Haemaphysalis parva (14.7%), Rhipicephalus turanicus (11.4%), and Haemaphysalis concinna (2.4%). Out of 344 specimens molecularly examined, 41 (11.1%) were positive for at least one microorganism (i.e. 5.5% for Cercopithifilaria bainae, 2.9% for Hepatozoon canis, 1.7% for Rickettsia hoogstraalii, 1.2% for Hepatozoon felis, 0.6% for Rickettsia massiliae, 0.6% for Theileria ovis, 0.3% for Anaplasma platys and 0.3% for Coxiella like-endosymbiont). The results of this study show that different tick species parasitize dogs in Greece, carrying a range of microorganisms potentially pathogenic for dogs and humans. Consequently, control strategies against ticks are of great importance to prevent the risk of tick-borne diseases. The relationship between ticks infesting dogs and associated microorganisms is described according to collection site and dog lifestyle.

Filarioids infecting dogs in northeastern Brazil

Species of filarial nematodes belonging to the genera Dirofilaria and Acanthocheilonema are recognised as common parasites of dogs throughout the world. Recently, other filarioids featured by the presence of dermal microfilariae (e.g., Onchocerca lupi and Cercopithifilaria spp.) have been recognised in Europe. In Brazil, reports of filarioids in dogs are limited to Dirofilaria immitis, Acanthocheilonema reconditum and Cercopithifilaria bainae. To investigate the distribution of filarial infections in dogs living in an endemic region from northeastern Brazil, blood and skin samples (n=104) were microscopically (modified Knott’s test and skin snip sediment examination) and molecularly evaluated. Twenty-two dogs (21.15%) were positive at microscopic and/or molecular examination for at least one filarioid species, with 21 (20.19%) animals positive for blood microfilariae at molecular and/or at microscopic examination. Microfilariae of D. immitis were detected in 12 (11.54%) animals, with co-infection of D. immitis and A. reconditum observed in four (3.85%) individuals. One animal was positive for C. bainae at both microscopic and molecular examination. Analysis of sequence obtained in the present study showed significant alignment identity with that of C. bainae from Europe. Considering that in the area of study arthropod vectors (mosquitoes, fleas and ticks) are prevalent throughout the year, preventive measures should be disposed in order to avoid the animal infestation and pathogen infection.

Occurrence of Hepatozoon canis and Cercopithifilaria bainae in an off-host population of Rhipicephalus sanguineus sensu lato ticks

Hepatozoon canis (Eucoccidiorida, Hepatozoidae) and the filarioid Cercopithifilaria bainae (Spirurida, Onchocercidae) are tick-transmitted infectious agents of dogs, highly prevalent in the Mediterranean basin in association with Rhipicephalus sanguineus sensu lato. Ticks were collected from the environment every 25±2 days in a confined location in southern Italy where a community of dogs lives, from August 2012 to July 2013. In order to study the occurrence of H. canis and C. bainae, 1091 tick specimens (770 adults; 271 nymphs, and 50 larvae) were dissected, and oocysts of H. canis and larvae of C. bainae were morphologically identified. Out of 1091 dissected ticks, 13.47% (n=147) were positive for H. canis, with the highest prevalence recorded in unfed adults (16.4%; 126/770), followed by nymphs collected as larvae and allowed to moult (14%; 7/50), unfed nymphs dissected immediately after collection (3%; 8/271), and adults collected as nymphs and allowed to moult (2%; 6/271). The highest number of H. canis-positive ticks (35.5%; 43/121; P<0.05) was recorded during the summer months (i.e., June–July). In addition, 6% of adult ticks (n=66) were positive for third-stage larvae of C. bainae, with the highest number in June (17%; 14/84; P<0.05). Based on the results reported herein, H. canis and C. bainae infections in the study area seem to be dependent on the seasonality of vector tick populations. Hence, dogs living in these areas are more exposed to both pathogens during the warmer months. These findings provide new insights into the ecology of both H. canis and C. bainae.

Cercopithifilaria spp. in dogs in Sardinia Island (Italy)

A survey on Cercopithifilaria spp. was carried out on owned and kennelled dogs in Sardinia, Italy. A total of 180 dogs were sampled and tested by microscopic detection or PCR of dermal microfilariae in skin snip sediments. The overall prevalence for Cercopithifilaria spp. at both microscopy and molecular tests was 9.4 % (17/180), while 8.3 % (15/180) of dogs scored positive at microscopic detection of sediments only. Of the 225 microfilariae measured, 212 were identified as Cercopithifilaria bainae and the remaining as Cercopithifilaria sp. II. All samples were molecularly processed for specific amplification of cytochrome oxidase subunit 1 (cox1) and ribosomal 12S gene fragments. The Basic Local Alignment Search Tool analysis of the cox1 and 12S sequences here obtained showed a high nucleotide similarity (99 and 100 %, respectively) with those of C. bainae available in GenBank. In particular, cox1 haplotype I (HI; n=14), haplotype HXVIII (n=2), and a new haplotype, named HXIX (n=1), differing for a single polymorphism from HI, were detected. This study reports data on the occurrence, distribution, and genetic makeup of C. bainae and Cercopithifilaria sp. II infesting dogs in Sardinia, suggesting that these filarioids are spread in areas where Rhipicephalus sanguineus sensu lato ticks occur.

Morphological and molecular data on the dermal microfilariae of a species of Cercopithifilaria from a dog in Sicily

Dermal microfilariae found in a dog from Sicily, Italy, were characterized morphologically and genetically and differentiated from those of all the other blood microfilariae commonly found in dogs. In particular, the microfilariae were short (mean length of 186.7μm), presented a body flattened dorso-ventrally and a rounded head, bearing a tiny cephalic hook. The genetic identity of microfilariae herein studied was also assessed by molecular amplification, sequencing and analyzing of multiple ribosomal ITS-2 and mitochondrial (cox1 and 12S) target genes. Both morphologic and genetic characterization as well as the molecular phylogenetic history inferred using sequences of a barcoding dataset were concordant in supporting the identification of Cercopithifilaria at the genus level. Surprisingly, microfilariae here examined were well distinct from Cercopithifilaria grassii (Noè, 1907), from northern Italy, and resembled those of a species described in Brazil, Cercopithifilaria bainae Almeida & Vicente, 1984. This paper provides evidence for the existence of a Cercopithifilaria species infesting a dog from Sicily and also presents a PCR protocol on skin samples as a tool for further epidemiological studies, which could provide evidence on the aetiology and the natural history of this filarial species.