Equine attachment site preferences and seasonality of common North American ticks: Amblyomma americanum, Dermacentor albipictus, and Ixodes scapularis.

BACKGROUND: Ticks are common on horses, but recent publications characterizing equine tick infestations in North America are lacking. METHODS: To further understand attachment site preferences of common ticks of horses, and to document the seasonality of equine tick infestation in northeastern Oklahoma, horses from eight farms were evaluated twice a month over a 1-year period. Each horse was systematically inspected beginning at the head and moving caudally to the tail. Attachment sites of ticks were recorded and all ticks collected were identified to species and stage. RESULTS: Horses (26 males and 62 females) enrolled in the study ranged in age from 1 to 23 years (mean = 12, 95% CI 11-13). A total of 2731 ticks were collected; 84.1% (74/88) of the horses were infested (median = 3 ticks) at one or more examinations. Five tick species were identified, including Amblyomma americanum (78.2%; 2136/2731), Ixodes scapularis (18.2%; 497/2731), Dermacentor albipictus brown variant (2.6%; 71/2731), Dermacentor variabilis (0.7%; 20/2731), and Amblyomma maculatum (0.3%; 7/231). Most ticks were adults (83.6%; 2282/2731), but immature A. americanum (436/2136; 20.4%), D. albipictus (12/71; 16.9%), and A. maculatum (n = 1) were occasionally recovered. Amblyomma americanum were most often attached to the inguinal area, and I. scapularis and D. albipictus were most commonly found on the chest and axillary region (P < 0.0001). Ticks were found on horses in every month of the year. The largest number of ticks (638/2731; 23.4%) were collected in May (P < 0.0001). Amblyomma americanum, primarily immature, was the only tick recovered in September, I. scapularis and D. albipictus predominated October through February, and both A. americanum and I. scapularis were common in March. In the warmer months, April through August, A. americanum was the most common tick, followed by D. variabilis and A. maculatum. CONCLUSIONS: This research confirms that ticks common on horses in North America have attachment site preferences and that ticks infest horses in Oklahoma throughout the year, including during the winter. Additional research is warranted to fully understand the risk these infestations pose to equine health.

Nondisseminated rhinosporidiosis with multisite involvement in the head and neck.

Rhinosporidiosis is a communicable disease prevalent in tropical countries that affects one or more mucocutaneous sites such as the nasal cavity, pharynx, skin, bronchus, genitals, and bone, in isolation or together. We report a case of multicentric rhinosporidiosis involving the nasal cavity, oropharynx, larynx, and cheek skin without disseminated disease outside the head and neck. Although the appearance of mucocutaneous lesions in our patient was similar to that of papilloma or neoplasm, the distinct clinicopathologic characteristics of the rhinosporidiosis guided us in managing the case successfully. In our own experience with 11 patients with rhinosporidiosis on whom we operated over the past 5 years, the nasal cavity and pharynx were the most commonly involved sites in the head and neck. Surgical excision of all lesions along with cauterization of the base and long-term dapsone therapy is the current standard of care for multicentric rhinosporidiosis.

Morphological and molecular characterization of Onchocerca fasciata (Nematoda, Onchocercidae) from dromedary camels (Camelus dromedarius) in Iran.

Skin nodules of Onchocerca fasciata Railliet and Henry, 1910 (Spirurida, Onchocercidae) are a common finding in dromedary camels, though with a minimal clinical impact. There is little information about the morphology, molecular make-up and pathological impact of this parasite. Onchocerca fasciata nodules (1.3-2.1 cm in diameter and 509-841 mg in weight) were detected on the neck region in 31.5% of dromedary camels examined in Kerman province, southeastern Iran. Of 38 isolated nodules, only 23 (60.5%) contained viable worms. Measurement and morphological analyses were performed on isolated female worms by light microscopy. The identification of O. fasciata specimens was confirmed by sequence analysis of two mitochondrial genes (12S rDNA and cox1), which showed 0.4% divergence from available O. fasciata sequences. In addition, a phylogeny of filarial nematodes was constructed, based on these two mitochondrial genes and five nuclear genes (18S rDNA, 28S rDNA, MyoHC, rbp1, hsp70); this indicated that O. fasciata belongs to clade ONC3 of Onchocercidae, with representatives of the genera Onchocerca and Dirofilaria. Within the genus Onchocerca, O. fasciata is grouped with bovine parasitic species and the human parasitic Onchocerca volvulus, which suggests an impact of domestication on the radiation of the genus. Data provided here on the distribution and morphology of O. fasciata contribute to the molecular identification and phylogenetic position of the species.

Cervical Lymphatic Filariasis in a Pediatric Patient: Case Report and Database Analysis of Lymphatic Filariasis in the United States.

Lymphatic filariasis is a mosquito-borne parasitic infection caused by Wuchereria bancrofti and Brugia spp. Commonly seen in tropical developing countries, lymphatic filariasis occurs when adult worms deposit in and obstruct lymphatics. Although not endemic to the United States, a few cases of lymphatic filariasis caused by zoonotic Brugia spp. have been reported. Here we present a case of an 11-year-old female with no travel history who was seen in our clinic for a 1-year history of painless left cervical lymphadenopathy secondary to lymphatic filariasis. We review the literature of this infection and discuss the management of our patient. Using the National Inpatient Sample (NIS), the largest publicly available all-payer inpatient care database in the United States, we also examine the demographics of this infection. Our results show that chronic lymphadenopathy in the head and neck is the most common presenting symptoms of domestic lymphatic filariasis. Diagnosis is often made after surgical lymph node excision. Examination of the NIS from 2000 to 2014 revealed 865 patients admitted with a diagnosis of lymphatic filariasis. Most patients are in the mid to late sixties and are located on the eastern seaboard. Eight hundred and twenty six cases (95.5%) were likely due to zoonotic Brugia spp. and 39 (4.5%) due to W. bancrofti. Despite being rare, these data highlight the need to consider filariasis in patients presenting with chronic lymphadenopathy in the United States.

Habitat use pattern of the giant parasitic nematode Crassicauda magna within the pygmy sperm whale Kogia breviceps.

The giant (>3 m) parasitic nematode Crassicauda magna infects kogiid whales, although only 3 studies to date have provided detailed descriptions of these worms, all based upon fragmented specimens. These fragments were found within the neck region of kogiids, an unusual anatomic site for this genus of parasites. C. magna is a species-specific parasite among kogiids, infecting only pygmy sperm whales Kogia breviceps, and with a primarily cervico-thoracic distribution. To date, however, the pattern of habitat use within the host and transmission path of this parasite remain unknown. We used detailed dissections (n = 12), histological examination of host tissues (n = 2), and scanning electron microscopy of excised nematodes (n = 7) to enhance our understanding of this host-parasite relationship. Results revealed that a critical habitat for the parasite is an exocrine gland in the whale's ventral cervical region. C. magna male and female tails were found intertwined within the glandular lumen, and eggs were observed within its presumed secretion, illuminating the transmission path out of the host. The cephalic ends of these worms were often meters away (curvilinearly), embedded deeply within epaxial muscle. A single worm's complete, tortuous 312 cm course, from the gland to its termination in the contralateral epaxial muscle, is described for the first time. This study also provides the first scanning electron micrographs of C. magna, which illustrate taxonomically important features of the heads and tails of both male and female worms.

Head and neck myiasis: a case series and review of the literature.

OBJECTIVE: This study describes 9 cases of myiasis affecting the head and neck region and discusses the demographic distribution, treatment, clinical characteristics, and sequelae of the disease in light of the literature. STUDY DESIGN: The study was performed in 2 steps. In the first part, 9 cases seen over a period of 10 years at the Emergency Department of Hospital da Restauração in Brazil were studied. In the second part, a literature search was performed in PubMed for articles on head and neck myiasis published from 1975 to March 2017. RESULTS: The case series mainly consisted of male patients in their 30s. The palate was the most commonly affected site. Myiasis was caused by Cochliomyia hominivorax in all patients, who were treated by mechanical removal of the larvae and debridement of necrotic tissue, followed by oral ivermectin. All patients had sequelae resulting from bone destruction. CONCLUSIONS: Head and neck myiasis generally affects individuals with poor hygiene habits, drug users, and individuals with neurologic and psychosocial disorders. The treatment of choice is mechanical removal of larvae and surgical debridement combined with oral ivermectin. This study provides information that could help clinicians in the diagnosis and management of this condition.

Hydatid Cyst of the Posterior Cervical Region.

Hydatid cyst is an endemically seen parasitic disease and caused by the larval form of Echinococcus parasites. The disease is mostly seen in liver and lung, and the other involvement is rarely seen. Head and neck involvement is extremely rarely seen and its frequency in the literature is reported as less than 1%. It is usually asymptomatic and the symptoms are related to the compression to the adjacent structures. In this paper, the authors report a patient of hydatid cyst localized in the posterior cervical region.

A Case of Lagochilascariasis in Suriname with the Involvement of the ENT System and the Skull Base.

We describe a case of human lagochilascariasis, with skull-base involvement and a chronic and relapsing course after treatment. This rare parasitic infection is usually manifested in the head and neck area, characterized by progressive granulomatous inflammation and the formation of abscesses. Transmission to humans most likely occurs by the consumption of undercooked meat of wild rodents. On the basis of literature studies, we propose the most likely life cycle of the parasite that involves wild feline and rodent species, with humans as accidental hosts. Even in endemic areas, it is very difficult to recognize the disease at an early stage. Progression will eventually lead to involvement of the (central) nervous system, as described in our case. Treatment is often difficult and involves resection and prolonged treatment with anthelmintic drugs. Recurrences are not uncommon and at present, long-term oral administration of ivermectin seems to be the most effective treatment.

Primary Giant Echinococcosis of the Neck.

The authors report an isolated echinococcosis in a 17-year-old girl presented with swelling of right neck approximately 12 cm in diameters with no evidence of the disease elsewhere in the body. A thorough search of the literature revealed only a few cases of isolated cervical echinococcosis. Surgical procedure was planned for our case with the guidance of the magnetic resonance imaging, which showed right cystic mass and within a laminar membrane. Histopathologic report confirmed echinococcosis. In summary, this current study shows that in the differential diagnosis of the cystic masses localized in the neck in the endemic regions, echinococcosis should be suggested. In these patients, the careful assessment of the magnetic resonance imaging evaluation before the surgery would extremely facilitate either the diagnosis or the surgery planning.

A rare, incidental submandibular hydatid cyst.

Hydatid cyst disease is a parasitic infestation caused by Echinococcus granulosus. It is transmitted via oral ingestion of eggs excreted by dog's stool. Liver and lungs are the most commonly involved organs. Primary involvement of submandibular region by hydatid cyst is extremely rare. In this article, we report a case of a lesion excised from submandibular region with an initial diagnosis of branchial cleft cyst, but shown to be a hydatid cyst in histopathological evaluation.

A rare case of Dirofilaria repens infection.

OBJECTIVE: This paper reports a case of Dirofilaria repens infection in a patient who presented with an anterolateral neck swelling. Dirofilaria repens infection of the neck region is rare even in countries where dirofilarial infestation is endemic. The diagnosis is made by identifying the worm in surgical or pathological specimens. CASE REPORT: A 47-year-old man presented with an 8-week history of non-tender, right-sided, lower anterolateral neck swelling and weight loss. An ultrasound scan showed a cystic lesion containing a living worm. The cyst was excised and the patient showed full recovery at follow up. CONCLUSION: To our knowledge, there has been no previous report of an anterolateral neck swelling secondary to Dirofilaria repens infection in Europe. Our case is unusual because of the rarity of Dirofilaria repens presenting as a neck swelling.

Factors affecting deer ked (Lipoptena cervi) prevalence and infestation intensity in moose (Alces alces) in Norway.

BACKGROUND: The deer ked (Lipoptena cervi), a hematophagous ectoparasite of Cervids, is currently spreading in Scandinavia. In Norway, keds are now invading the south-eastern part of the country and the abundant and widely distributed moose (Alces alces) is the definitive host. However, key factors for ked abundance are poorly elucidated. The objectives of our study were to (i) determine deer ked infestation prevalence and intensity on moose and (ii) evaluate if habitat characteristics and moose population density are determinants of deer ked abundance on moose. METHODS: In order to identify key factors for deer ked abundance, a total of 350 skin samples from the neck of hunted moose were examined and deer keds counted. Infestation intensity was analyzed in relation to moose age and sex, moose population density and landscape characteristics surrounding the killing site. RESULTS: Deer ked infestation prevalence was 100%, but infestation intensity varied from 0.001 to 1.405 keds/cm². Ked intensity was highest in male yearlings (~1.5 years) and positively associated with longitude and Scots pine (Pinus sylvestris) dominated habitat and negatively associated with bogs and latitude. Moose population density during autumn showed a tendency to be positively associated, while altitude tended to be negatively associated with ked intensity. CONCLUSIONS: Deer keds exploit the whole moose population within our study area, but are most prevalent in areas dominated by Scots pine. This is probably a reflection of Scots pine being the preferred winter browse for moose in areas with highest moose densities in winter. Ked intensity decreases towards the northwest and partly with increasing altitude, probably explained by the direction of dispersal and reduced temperature, respectively. Abundant deer ked harm humans and domestic animals. Moose management authorities should therefore be aware of the close relationship between moose, deer ked and habitat, using the knowledge as a management tool for locally regulating the ked burden.

Cervical sparganosis: case reports with focus on radiological findings.

BACKGROUND: Cervical sparganosis is a rare condition that presents as a lateral neck mass. Its radiological findings have not previously been investigated. Thus, the important radiological findings of cervical sparganosis are presented herein. METHODS: We report two patients with cervical sparganosis who presented with cervical masses, and we review the relevant head and neck literature. Computed tomography was performed three times over 13 months of follow up for one patient. RESULTS: On follow-up radiological examination, a migratory lesion with a tubular appearance, seen on serial images, should be considered significant for cervical sparganosis. CONCLUSION: Radiologically, a migratory cervical mass in the head and neck area with a tubular appearance is suggestive of cervical sparganosis.

Cutaneous myiasis in a malignant wound of the head and neck region.

Myiasis is a parasitic infestation of vital tissue of humans or other mammals by dipterous larvae. Human myiasis is a rare clinic condition but more frequently seen in tropical and subtropical areas, in patients who have poor hygiene, have bad housing conditions, are with mental retardation, or have advanced age. We report a case of myiasis in a malignant wound (squamous cell carcinoma) in the head and neck region because a few literature reports were seen in this localization. The patient's treatment was antisepsis, larval removal, and general care preventions, whereas standard treatment options or guidelines are not available.

[Cervico-facial hydatidosis. Report of 17 cases]. / L'hydatidose cervico-faciale. A propos de 17 cas.

BACKGROUND: Cervico-facial hydatid cyst is rare. It accounts for 1 % of echinococcosis locations. AIM: To describe the epidemiological, clinical and therapeutic aspects of cervico-facial hydatid cysts based on our clinical experience and data in the literature. METHODS: A retrospective study was made concerning 17 patients with cervico-facial hydatid cyst treated surgically over a 25-year period from 1982 to 2006. RESULTS: Mean patient age was 27 years (range 2-79). Hydatid cyst localization was: cervical muscle (7 cases), thyroid gland (5 cases), parotid gland (2 cases), cervico-thoracic (1 case), larynx (1 case) and cheek (1 case). Hydatic origin of the cyst was suspected for 6 patients (35.3 %) preoperatively. Surgical treatment was used in all cases and adapted to each case. Diagnosis was always confirmed by macroscopic aspects and pathology. CONCLUSION: Hydatid cysts are rarely found in the cervico-facial region, even in highly endemic zone. The manifestation of symptoms depends on the location and the size of the cyst. Positive diagnosis can be difficult during preoperative period. Exclusively surgical treatment is indicated, ideally for total pericystic resection without rupture.

Primary subcutaneous hydatid cysts: a review of 22 cases.

AIM: We aimed to review cases of primary subcutaneous hydatid cysts whether this is a fearsome disease or a benign progressed pathology. These cysts are rare, have difficulty in diagnosis and management, particularly for inexperienced clinicians. METHODS: We searched key words of "echinococcosis, hydatid, soft tissue, subcutaneous, cutaneous" at MEDLINE/PUBMED. We eliminated unrelated articles, cases with primary visceral hydatid focus or muscular cysts. Twenty publications including 22 patients were suitable for analysis. We contacted with authors of the articles for missing data. Follow-up periods and recurrences were updated. RESULTS: All patients were from endemic areas and most from rural regions (90%). Most frequent locations were thigh (27%) and gluteal region (9%). Mean size was 5.7 + 3.1 cm (2-15 cm). Main symptom (70%) was painless, slow growing mass with normal overlying skin. Serologic tests were usually negative (79%). Only 45% of the patients were diagnosed as hydatid cyst before treatment. Most cases (91%) were treated by surgical excision and spillage occurred at 25% of them. Cyst pouchs were irrigated with protoscolocidal solutions after cyst removal. There was no anaphylaxis during procedures. There was no recurrence with a mean follow-up of 26 + 18 months (6-60 months). CONCLUSION: Primary subcutaneous hydatid cyst should be in mind for differential diagnosis of soft tissue masses particularly for patients who lived in regions where hydatid cyst is endemic. There is no reported anaphylaxis or recurrence during diagnostic or therapeutic interventions. Complete excision is the best treatment option. Primary subcutaneous hydatid cysts generally look like a benign progressed disease.