Efficacy of eprinomectin 5 mg/mL topical solution administered pour on at 1 mg per kg body weight against Oestrus ovis myiasis in sheep and goats

The larvae of the nasal bot, Oestrus ovis, mainly parasitize sheep and goats and some species of wild Caprinae but other mammals and humans are also vulnerable to infestation. Eprinomectin 5 mg/mL topical solution (EPRINEX® Multi, Boehringer Ingelheim) administered at 1 mg eprinomectin per kg body weight pour on was recently authorized as an anthelmintic for sheep and goats with zero hours milk withdrawal in several countries in Europe. As the product in cattle has claims against a broad range of parasites including insect parasites and activity against O. ovis has previously been reported following extra-label use in sheep, its therapeutic efficacy against ovine and caprine O. ovis myiasis was evaluated in three regulatory compliant, masked clinical studies. Pre-study recovery of O. ovis larvae from five or six of six randomly selected animals per study site (Bulgaria, one site, sheep; Greece, two sites, sheep or goats) supported the inclusion of the animals from those sites into the studies. The study animals (34 animals per study) were ranked based on bodyweight and allocated randomly to remain untreated (control) or to be treated with eprinomectin 5 mg/mL topical solution at 1 mL per 5 kg body weight pour on. Treatment efficacy was determined based on O. ovis larval counts of eprinomectin 5 mg/mL topical solution-treated vs. untreated animals three weeks after treatment administration. Live O. ovis larvae, including all three instars in each study, were recovered from 13 or 16 of the 17 control animals in the sheep studies (range, 1 to 14 or 5 to 18 larvae, respectively) and from all 17 controls in the goat study (range, 7 to 18 larvae). In each study, eprinomectin 5 mg/mL topical solution-treated animals had significantly (p < 0.001) fewer live O. ovis larvae than the controls. Efficacy of the treatment was 100% and 91.3% against the combined parasitic O. ovis larval stages in sheep and in goats, respectively. The treatment was well accepted by all animals and no health problems were observed throughout the studies. The results of these studies demonstrated eprinomectin 5 mg/mL topical solution administered pour on at 1 mL per 5 kg body weight to be an efficacious and safe treatment of ovine and caprine oestrosis.

Retrospective study of Oestrus ovis larvae infestation in small ruminants in Grenada, West Indies

Oestrosis is a nasal cavity myiasis caused by Oestrus ovis larvae from Oetrus ovis diptera flies in small ruminants. The presence of the larvae in the nasal cavity is known to cause rhinitis and sinusitis which can negatively impact the productivity of small ruminants. The aim of the present study was to estimate the prevalence of Oestrus ovis larvae infestation in sheep and goats presented for necropsy. We reviewed necropsy records of sheep and goats submitted to the Veterinary Pathology diagnostic laboratory at St. George's University from 2001 to 2017. Out of 104 goat necropsy cases, Oestrus ovis larvae were observed in 8 goats giving a prevalence of 7.7% (95% confidence interval (CI):3.38% to 14.6%). Similarly, from the 47 sheep necropsies, Oestus ovis larvae were observed in 4 sheep (8.5%) (95% CI: 2.83% to 20.46%). There was no significant difference in Oestrus ovis larvae infestation rates between sheep and goats (p = 1.000, Fisher's exact test). Oestrosis was an incidental finding in all the small ruminants examined at necropsy. This is the first report on Oestrus ovis larvae infestation in small ruminants in Grenada.

Ophthalmomyiasis Externa and Importance of Risk Factors, Clinical Manifestations, and Diagnosis: Review of the Medical Literature

OBJECTIVE

This review aims to describe and compare the risk factors, clinical course, diagnosis, and parasitologic features of external ophthalmomyiasis. We also discuss the different preventive measures and the effect of global warming in a large case series reported from January 2000 to December 2022.

METHODS

We perform a literature review of reported cases of external ophthalmomyiasis to determine the clinical characteristics, therapeutic management, and information on the organisms that most commonly cause external ophthalmomyiasis.

RESULTS

A total of 312 cases of external ophthalmomyiasis were recorded. The most common causative organism was Oestrus ovis (Linnaeus) (Diptera: Oestridae), accounting for 72.1% of cases, followed by Dermatobia hominis (Linnaeus Jr. in Pallas, 1781) (Diptera: Oestridae) at 5.4%, Lucilia sericata (Meigen) (Diptera: Calliphoridae) at 0.96%, and Chrysomyia bezziana (Villeneuve) (Diptera: Calliphoridae) at 0.96%. Before experiencing symptoms, 43.6% of cases reported having direct contact with flies or being hit in the eye, 33% reported no associated risk factors, 9.3% reported living with sheep and goats, and 7.7% reported a history of foreign objects entering the eye. The most common symptoms for those affected by O. ovis were sudden onset, including a foreign body sensation and movement, redness, tearing, itching, swelling, irritation, photophobia, burning, and ocular secretion. In cases caused by D. hominis, symptoms included eyelid edema, pain, redness, itching, movement within the lesion, ocular irritation, and discharge. Regarding occupational or recreational activity, agriculture, and livestock had the highest incidence, followed by trades and technical activities, being a student, and having traveled to an endemic region for work or recreation.

CONCLUSION

Patients with red eyes may suffer from external ophthalmomyiasis, which requires a thorough examination to diagnose and treat it early. Moreover, as the temperature increases due to climate change, it is essential to consider how this will affect the spread of different pathogens.

Prevalence of Oestrus ovis in small ruminants from the eastern Iberian Peninsula. A long-term study

Oestrus ovis is an obligate parasite that causes myiasis in domestic ruminants, being commonly found in the Mediterranean area. From 2009 to 2019 a total of 3476 heads of culling sheep and goats from the Mediterranean coast of Spain were examined for the presence of O. ovis. The total prevalence was 56.3%, significantly higher in sheep than in goats (61.2% and 43%, respectively). Differences were found in the mean annual prevalence, with the highest value being registered in 2018 (61.7%) and the lowest in 2012 (50.3%). Autumn, for sheep, and winter, for goats, were the seasons with the highest number of infested specimens. Temperature, but not rainfall, was found to be associated with prevalence (p < 0.05). Most L1 were found in the anatomic region I (septum, meatus, and ventral conchae), while L2 and L3 were mainly located in regions II (nasopharynx, ethmoid labyrinth, and dorsal conchae), and III (sinuses). The overall intensity was 12.8 larvae per head, significantly higher in sheep (13.3) than in goats (3.5). Our results confirm the high prevalence of O. ovis in sheep and goats in this geographic area over the last decade, with the trend increasing in recent years in association with higher mean temperatures.

Ophthalmomyiasis Externa due to Oestrus ovis Larvae: A Case Report

A 23-year-old female presented with redness, itchiness, tearing, and foreign body sensation in her right eye after spending her holiday in Egypt. Slit lamp examination revealed about 15 mobile, whitish maggots that were microbiologically classified as Oestrus ovis larvae. All parasites could be removed without subsequent complications.

Morphological and Molecular Identification of Oestrus ovis (Diptera: Oestridae) Larvae Collected from a Chinese Patient with Conjunctival Myiasis

PURPOSE

Human conjunctival myiasis, which is often misdiagnosed or missed clinically, is commonly caused by Oestrus ovis larvae. Here, pathogenic identification was performed for two maggots collected from a patient from China, to provide a clinical scientific basis for diagnosis and treatment.

METHODS

Morphological identification was performed using a microscope. Oestrus mtDNA cox1 and rDNA 28S were selected as target genes for duplex PCR amplification, followed by cloning, sequencing, and identification.

RESULTS

Morphological examination showed that the maggots were approximately 1.0-1.5 mm long, long-oval-shaped, segmented, and covered with small spines, with a pair of hooks in the scolex and claw-like spines at the telson. Therefore, they were identified as the first-instar larvae of O. ovis. Duplex PCR detected products of approximately 400 and 200 bp, consistent with the size of designed cox1 and 28S D7a gene fragments, respectively. Sequences of cox1 and 28S D7a from the samples in question had 99.5-100.0% and 96.2-100.0% similarity (respectively) to GenBank sequences of O. ovis specimens known to parasitize sheep, goats, and humans. However, some 28S D7a sequences exhibited 89.7-90.6% similarity to GenBank sequences of Oestrus sp. known to parasitize Capra pyrenaica (Artiodactyla: Bovidae) (Iberian ibex). Therefore, we considered that the larvae infecting the patient originated from sheep or goats, not Iberian ibex. The phylogenetic trees supported this conclusion.

CONCLUSION

This study implemented the first duplex PCR molecular identification of O. ovis larvae parasitizing human eyes in China as a complementary approach to morphological identification. Our results indicate that molecular tools can be utilized to aid in the diagnosis of opthalmomyiasis.

External Ophthalmomiasis Cases in Şırnak

Dermatological cases caused by myiasis make up approximately 20% of travel diseases. Ocular involvement occurred in approximately 5% of these myiasis cases. The conjunctival involvement of Oestrus ovis (O. ovis) larvae, which is the active agent in most ocular infestation cases in humans, causes external ophthalmomyiasis. External ophthalmomyiasis was diagnosed because of O. ovis first-stage larvae that were removed from the conjunctiva of three patients who applied to the Şırnak State Hospital Eye Clinic with complaints of foreign body sensation, burning, stinging, watering, and redness in the eyes and swelling of the eyelids in July and October. All symptoms of the patients disappeared within a few days after the removal of the larvae. Ophthalmomyiasis due to O. ovis must be kept in mind in the differential diagnosis of patients presenting with similar eye complaints in areas where sheep and goat husbandry is performed intensely.

External ophthalmomyiasis by Oestrus ovis in tourists visiting Italy. Report of three cases and a literature review

BACKGROUND

Oestrus ovis is a dipteran parasite responsible of myiasis in small ruminants and reported as the causative agent of myiasis in humans particularly in sheep farming areas. In recent years, several human cases had been reported without any previous history of exposure to livestock or visit to rural areas.

CASE PRESENTATION

We describe three clustered cases of ophthalmomyiasis externa in tourists in Sardinia and Sicily and discuss them in the light of the published literature. The patients presented ocular irritation, foreign body sensation, pain, redness, and lacrimation of the eyelids. After extraction, all the larvae were morphologically and molecularly confirmed as L1 instar of O. ovis larvae.

CONCLUSIONS

The present study points out the need to draw attention and awareness among the physicians, and to consider ophthalmomyiasis when consulted for conjunctivitis in the summer and spring seasons.

A silent, trapped guest in the maxillary sinus: Oestrus ovis myiasis with unusual presentation (with CARE guideline)

INTRODUCTION

A sheep bot fly, Oestrus ovis, is an obligate parasite that is found worldwide, especially widespread in the Mediterranean areas and Middle Eastern. Interestingly, in this report, a case with an L3 larva trapped in the human maxillary sinus with other stage larvae is presented.

CASE SUMMARY

A 32-year-old female patient has no symptoms until the larva is expelled by sneezing. Endoscopic examination was normal on admission. Paranasal sinus computed tomography (CT) revealed left maxillary sinus soft tissue density. Uncinectomy and middle meatal antrostomy was performed to remove the infection and larvae.

DISCUSSION

Human ophthalmic and nasopharyngeal myiasis have been documented but asymptomatic maxillary sinus myiasis is unusual and not reported. Due to changes in environmental factors, this atypical infection may occur with an unexpected presentation.

The complete mitochondrial genome of Oestrus ovis (Linnaeus, 1758) (Diptera: Oestridae)

Larvae of the sheep bot fly, Oestrus ovis (Linnaeus, 1758), cause cavitary myiasis in domestic and wild hosts, including man. The complete circular O. ovis mitogenome was assembled, which is 16,584 bp in length and encodes 13 protein-coding genes, 22 tRNA genes, and two rRNA genes. The phylogenetic tree of O. ovis and 13 related Oestridae species, with Sarcophaga tuberosa as outgroup, was built.

Prevalence Rate and Molecular Characteristics of Oestrus ovis L. (Diptera, Oestridae) in Sheep and Goats from Riyadh, Saudi Arabia

Heads of sheep (n = 600) and goats (n = 800) slaughtered at Al-Aziziah Abattoir in Riyadh, Saudi Arabia, were inspected for the presence of O. ovis larvae (L). Heads were split along the longitudinal axes, and larvae (L1, L2, and L3) were gathered. The infestation rate was significantly higher in goats (44.5%; 356/800) than that in sheep (22.3%; 134/600). Out of the 151 collected larvae from sheep, 0% were L1, 1.3% were L2, and 98.7% were L3. Out of the total of 468 larvae from goats, 0% were L1, 1.2% were L2, and 98.8% were L3. The infestation rate was significantly higher in males than that in females. Myiasis-causing larvae collected from Riyadh, Saudi Arabia, were authenticated as O. ovis, according to morphological characteristics. Polymerase chain reaction (PCR) amplification of a partial fragment (600 bp) of the mitochondrial cytochrome c oxidase subunit I (mtCOI) gene further confirmed the species. Phylogenetic analysis based on the partial mtCOI gene sequence demonstrated that 23 unique sequences showed high similarity based on nucleotide pairs of O. ovis accessions retrieved from GenBank.

Major differences in the larval anatomy of the digestive and excretory systems of three Oestridae species revealed by micro-CT

Oestrid flies (Diptera: Oestridae) do not feed during the adult stage, so they depend on an efficient assimilation and storage of nutrients during their parasitic larval stage. We describe the general morphology and provide volumetric data for the digestive and excretory organs of the three larval instars of the nasal bot fly Oestrus ovis L., using micro-computed tomography. The size of the digestive and excretory organs greatly increased across larval instars. In all instars, the two salivary glands were remarkably large and formed a 'glandular band' by coming together, but without lumina uniting, at their posterior ends. The distal region of the anterior Malpighian tubules was greatly enlarged and full of highly radio-opaque concretions. Moreover, the anatomy of O. ovis third-instar larva was compared to that of two species of, respectively, similar and different feeding habits: Cephenemyia stimulator (Clark) and Hypoderma actaeon Brauer. Whereas the general morphology and arrangement of the digestive and excretory systems of C. stimulator was similar to that of O. ovis, some differences were observed in H. actaeon: a swollen anterior region of the midgut, salivary glands shorter and not forming a 'band' and anterior Malpighian tubules narrowly uniform throughout their entire length.

Molecular Characterization and Phylogenetic Analyses of Oestrus ovis Larvae Causing Human Naso-pharyngeal Myiasis Based on CO1 Barcode Sequences

Objective

The identification and molecular characterization of the bot fly larvae from an infected human with naso-pharyngeal myiasis in Turkey were aimed in this study.

Methods

A total of 8 bot fly larvae from a 49-year-old woman with naso-pharyngeal infection in Adana province constituted the materials of this study. Morphological identification was performed on the larvae according to described keys. The barcode region of the CO1 gene from the genomic DNA extracts of the larvae was amplified and sequence analyses were utilized. Haplotype and genetic distance analyses were performed in CO1 sequences and a phylogenetic tree was built revealing phylogenetic relationships.

Results

All bot fly larvae were identified as second stage larvae of Oestrus ovis in terms of morphologic characteristics. There was no polymorphism among the CO1 sequences of all isolates leading to detection of a single novel haplotype. The newly characterized haplotype in this study clustered with the O. ovis haplotypes from Bosnia and Herzegovina, Croatia, Brazil, and Iran in a monophyletic clade with an overall identity of 99.5%. Interspecific genetic differences among the subfamilies of Oestridae were in the range of 19.8% to 30.8%.

Conclusion

This study has provided the first molecular characterization data on O. ovis larvae from an accidental human host in Turkey based on CO1 barcode sequences.

Ophthalmomyiasis Externa: A Case Report

Ophthalmomyiasis is the infestation of the eye with fly larvae. Oestrus ovis is one of the most common causes of ophthalmomyiasis worldwide. Herein, we describe a case of external ophthalmomyiasis caused by Oestrus ovis in an 18-year-old female living in the city centre of Istanbul and who had no history of contact with any animal.

The First Genetically Confirmed Case of Human Ophthalmomyasis Due to Oestrus ovis (Diptera Oestridae) in Bosnia and Herzegovina

PURPOSE

Here we present a case of human ophthalmomyasis due to Oestrus ovis in a patient living in an urban area. Dipterians of the Ostridae family may occasionally deposit larvae into the human eye and cause ocular parasitosis called ophthalmomyasis. Cases like this are mostly connected with people who live in close contact with animals, like shepherds, but are rarely presented in urban population.

METHODS

The patient was presented at University Clinic due to problems with his left eye, that persist no matter on treatment in local clinic a few days before. During the slit lamp examination larvae was detected and extracted from the conjunctiva. Genomic DNA was isolated from the sample and genetic analysis was performed.

RESULTS

Larvae was identified as a first-stage larvae of O. ovis.

CONCLUSION

This is the first report of genetically confirmed case of ophthalmomyasis in Bosnia and Herzegovina. In cases like this, clinicians should be aware of possibility of this rarely described presentation of ocular parasitosis since even the urban population can be accidentally affected due to a lack of natural hosts.

Development and characterization of 15 novel polymorphic microsatellite loci for two important bot flies (Diptera, Oestridae) by next-generation sequencing

Cephenemyia stimulator and Oestrus ovis are two important parasitic bot flies (Oestridae) species causing myiasis, with a potential negative impact on the welfare of the host. Using next-generation sequencing approach and bioinformatics tools, a large panel of possible microsatellites loci was obtained in both species. Primer pairs were designed for 15 selected microsatellite loci in C. stimulator and other 15 loci in O. ovis for PCR amplification. Loci amplification and analysis were performed in four populations of each species. The results demonstrated that all selected loci were polymorphic, with the number of alleles ranging from 2 to 6 per locus in C. stimulator and 3 to 13 per locus in O. ovis. This is the first time to describe these microsatellite loci for C. stimulator and O. ovis. These two sets of microsatellite markers could be further used for biogeographic and population genetics studies.

Evaluation of tumor necrosis factor-alpha (TNF-α); gamma interferon (IFN-γ) genes and oxidative stress in sheep: immunological responses induced by Oestrus ovis (Diptera: Oestridae) infestation

This study aimed to evaluate the cell mediated immune responses against Oestrus ovis (O. ovis) in sheep through measurement of the changes in mRNA expression of the tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ) cytokines using quantitative Real time-PCR (qRt-PCR). Also; to detect the role of Oestrus ovis infestation in the oxidative stress markers in sheep. Fifty sheep head were examined in Cairo abattoir from the period of May to August 2019. Sera were separated and collected for measurement of nitric oxide, zinc and malondialdehyde (MDA). While TNF-α and IFN-γ mRNA were extracted from nasal mucosa. Levels of IFN-γ and TNF-α were significantly higher in infested sheep than that in non-infested one. Also, oxidative stresses were indicated by high level of nitric oxide as one of reactive oxygen species (ROS) and serum MDA as oxidative stress marker and low antioxidant capacity (zinc concentration in serum) in infested sheep. The obtained results indicated that measurements of TNF-α and IFN-γ cytokines using qRT-PCR could be used as an association and reproducible quantitative method for the diagnosis of O. ovis infestation in sheep.

External ophthalmomyiasis by Oestrus ovis: A case report from Davangere

External ophthalmomyiasis is an infestation of the eye with larvae of Dermatobia hominis or Oestrus ovis (sheep bot fly). We describe a case of ophthalmomyiasis in a 38-year-old male, who presented with ocular foreign body sensation, redness, pain, and watering of the eye. The causative larvae were removed and sent to the laboratory for identification. By studying morphological features, it was identified as the first instar larvae of O. ovis. The patient was put on topical and oral antibiotics but was lost to follow-up. This is probably the first report from this part of Karnataka.

Rhinomyiasis by Oestrus ovis in a tourist returning from Corsica

In the Mediterranean basin, one of the most important agents of myiasis is Oestrus ovis Linnaeus 1758 (Diptera, Oestridae). Herein, we report a rare case of nasal myiasis with a secondary infection complication in a patient from northern Italy who had been visiting Corsica. A healthy, 39-year-old Italian woman spent 2 weeks of vacation in Corsica in June 2018. During her stay, she suddenly felt a foreign body inside her nose, followed by cough, pain, burning at the pharyngeal level, cephalalgia, and nasal congestion with secretions from the nostrils. The clinical examination showed a hyperemic and irritated mucosa and endoscopic examination of the patient's nose and right maxillary sinus revealed three tiny mobile larvae, morphologically and molecular identified as L1 instar larvae of Oestrus ovis. The patient's infestation was probably imported from Corsica, as Mediterranean islands are ideal geographical areas for the development of O. ovis, and the timing of infestation match with the period of O. ovis larviposition. Although rhinomyiasis is rare, it should be considered in people returning from abroad presenting with an acute-onset and foreign body sensation in the nose.

Oestrus ovis in Ecuador: Importance in the Andean sheep farming

Aim

This study aimed to determine the prevalence of Oestrus ovis in sheep meant for meat commercialization in the main slaughterhouse of the country.

Materials and Methods

Between October 2015 and December 2015, we assessed the occurrence of Oestrus myiasis in the main slaughterhouse localized in Quito. In total, 80 sheep heads were randomly inspected and necropsied. Larvae were removed from nasal cavities and paranasal sinuses and cleaned. ANOVA (generalized linear model) was used to estimate the relationship between sex, age, and place of origin and presence or absence of parasite larvae.

Results

Morphological identification confirmed that 19% (15/80) of the examined animals were positive for Oestrus ovis; from the positive cases, 21% were young animals <12 months old. We found that statistical differences by animal sex, males, were most infested 93% (14/15) than females 7% (1/15). Larvae's L2 were more abundant than other stages (62 of the total 149). 14 of the infested animals were from the Andean places at > 2500 meters above sea level (m.a.s.l.), and only one case from the coastal region at 250 m.a.s.l. with tropical environmental conditions.

Conclusions

Our results showed evidence of the presence of myiasis caused by O. ovis in Andean and coastal places in Ecuador and its adaptation to different environmental conditions from that reported previously in temperate regions from Europe and Africa.

Oestrus ovis external ophtalmomyiasis: a case report in Burgundy France

BACKGROUND

External ophtalmomyiasis (EOM) is a zoonosis related to the presence of Oestrus ovis larvae at the ocular level in small ruminants (i.e. ovine, caprine). In humans, EOM is a rare cosmopolitan disorder, mostly described in warm and dry rural areas in patients living close to livestock areas. In metropolitan France (excluding Corsica), EOM is an exceptional disease with less than 25 cases recorded since 1917.

CASE PRESENTATION

We report a case of EOM in a 19-years old man in the last week of September 2016 in Burgundy.

CONCLUSION

The diagnosis of an EOM in Burgundy, a French region described as cold and humid, is surprising and could be due to a more marked climatic warming during the vegetative season in Burgundy resulting in the implantation of Diptera of the genus Oestrus sp. in this region.

Ophthalmomyiasis externa due to sheep nasal botfly in rural Jamaica

We present the case of a young male patient who presented with pain, redness and foreign body sensation in his left eye. There was no associated decrease in vision. Three live larvae were removed from his left conjunctival sac and sent to the laboratory for identification. The patient was treated symptomatically and his symptoms were mostly resolved by the following day. The larvae were later identified as the first instar of the sheep nasal botfly. Poor sanitation and exposure to livestock were among the identified risk factors in this case. Physicians must have this as a differential diagnosis for conjunctivitis in patients with risk factors. This is the first reported case of ophthalmomyiasis from Jamaica.

Ocular external myiasis. A series of cases due to larvae Oestrus ovis in Navarra, Spain

OBJECTIVE

To report a case series of external ophthalmomyiasis in a region of Spain together with its common epidemiological factors and treatment.

MATERIAL AND METHODS

A presentation is made of four clinical cases of patients with external ocular myiasis caused by Oestrus ovis larvae.

RESULTS

Ocular myiasis is a parasitic infection by larval stages of flies. It can affect the ocular globe externally and / or internally, with the former being the most frequently found condition. The organism that mainly affects the eyes is the Oestrus ovis larvae.

CONCLUSION

Ocular external myiasis is a rare condition that occasionally can occur in humans. In this case series, a common risk factor for infection is established: the previous exposure to livestock and / or agricultural activity. An adequate diagnosis and treatment could avoid the transition from external to internal form, as well as its complications.

Micro-computed tomography visualization of the vestigial alimentary canal in adult oestrid flies

Oestrid flies (Diptera: Oestridae) do not feed during the adult stage as they acquire all necessary nutrients during the parasitic larval stage. The adult mouthparts and digestive tract are therefore frequently vestigial; however, morphological data on the alimentary canal in adult oestrid flies are scarce and a proper visualization of this organ system within the adult body is lacking. The present work visualizes the morphology of the alimentary canal in adults of two oestrid species, Oestrus ovis L. and Hypoderma lineatum (de Villiers), with the use of non-invasive micro-computed tomography (micro-CT) and compares it with the highly developed alimentary canal of the blow fly Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). Both O. ovis and H. lineatum adults showed significant reductions of the cardia and the diameter of the digestive tract, an absence of the helicoidal portion of the midgut typical of other cyclorrhaphous flies, and a lack of crop and salivary glands. Given the current interest in the alimentary canal in adult dipterans in biomedical and developmental biology studies, further understanding of the morphology and development of this organ system in adult oestrids may provide valuable new insights in several areas of research.

A case of ophthalmomyiasis interna in the Pacific Northwest

PURPOSE

We report a case of ophthalmomyiasis interna successfully removed in toto with pars plana vitrectomy.

OBSERVATIONS

An 84-year-old woman with recent close contact with lambs presented with a new floater. Examination revealed subretinal tracks pathognomonic for ophthalmomyiasis and a larva suspended in the vitreous. The larva was successfully removed in toto with pars plana vitrectomy by aspiration through the vitreous cutter.

CONCLUSIONS AND IMPORTANCE

Aspiration with pars plana vitrectomy can be considered a primary therapeutic modality for botfly larvae suspended in the vitreous. In our case, in toto removal of the larvae reduced the risk of inflammatory reaction.

Pharyngeal Myiasis Caused by Sheep Botfly, Oestrus ovis (Diptera: Oestridae) Larva, Tabriz, East Azarbaijan Province, Iran: a Case Report

Myiasis is caused by the larvae of flies infesting animal or human tissues and organs. This report aims to present a case of pharyngeal myiasis caused by the larvae of Oestrus ovis (Diptera: Oestridae). A 55-yr old drug addict living in the Shahindeje village of Western Azerbaijan Province, northwestern Iran was referred to the Emam Reza Hospital in Tabriz, having a medical history of Chronic Obstructive Pulmonary Disease (COPD) and hospitalized due to respiratory distress, 20 days ago. He was intubated with a mechanical ventilator (MV) because of his respiratory distress condition. There was an evidence of the presence of pulmonary nodules in his lungs following diagnosis, and a CT scan revealed a cavity in his lung. During the nasogastric intubation procedure, a larva was seen emerging from the patient's mouth by one of the staff of the intensive care unit of the hospital. A laboratory diagnosis was performed in the Entomology Department of the School of Medicine, Tabriz University of Medical Sciences. Interestingly, larvae of O. ovis were identified and confirmed following the laboratory proceedings.

Unilateral conjunctivitis of unique etiology: A case report from Eastern India

A middle-aged female patient from West Bengal presented with complaints of redness, foreign body sensation, and watering for 2 days in the left eye. Slit lamp examination of the left eye revealed several minute white foreign bodies moving over the bulbar conjunctiva. Removal of the foreign bodies under local anesthesia, followed by microscopic examination, suggested the presence of first instar larvae of Oestrus ovis; the sheep nasal bot fly. Diagnosis of unilateral external ophthalmomyiasis was made. Such cases though very infrequently have been reported in the past from Southern and Central Part of India. To the best of our knowledge, this is the second report from Eastern India. A high index of suspicion is necessary both on the part of the clinician and the microbiologist for correct diagnosis.

External ophthalmomyiasis: a case series and review of ophthalmomyiasis in Turkey

Ophthalmomyiasis externa is the infestation of the superficial external ocular structures by fly larvae. This is a particularly rare condition, which has nevertheless been reported in several countries worldwide. It is common in sheep-farming areas, especially in Mediterranean countries. The patients may present with classic conjunctivitis, pseudomembranous conjunctivitis, conjunctival hemorrhages, punctuate keratitis, keratouveitis, and eyelid edema with erythema. Herein, we present three cases of external ophthalmomyiasis caused by Oestrus ovis larvae and review ophthalmomyiasis cases reported from Turkey.

Diagnosis of ophthalmomyiasis externa by dermatoscopy

Ophthalmomyiasis in humans caused by the larvae of the sheep nasal botfly (Oestrus ovis) and is a rare phenomenon in Israel. We describe the utilization of the dermatoscope as a diagnostic tool for the facilitation of early diagnosis of conjunctivitis due to the infestation of the eyes by the sheep nasal botfly in two patients. After the physical removal of the larvae with the help of a cotton swab applicator under a slit lamp examination and the topical use of antibiotics, the clinical symptoms improved within 1-2 days. Undoubtedly the dermatoscope played a crucial role leading to the definitive diagnosis and immediate therapeutic intervention.

Nasal Oestrosis in a Jamunapari goat

Oestrus ovis is a well-known parasite of the nasal cavities and adjoining sinuses in sheep and goats. A 3-year-old female Jamunapari goat was presented with a history of anorexia, weight loss, in-coordinated movements, nasal discharge since 10 days and two nasal bots expelled during sneezing 3 days back. Upon clinical examination the animal was dull, dysphonic, unsteady gait and having blocked nostrils with thick mucoid discharge along with an increased respiratory rate. Parasitiological examination revealed it as an O. ovis (nasal bots). The occurrence of nasal bots in a goat and its successful therapeutic management and public health significance have been reported and discussed in the present communication.

Isolation and identification of excretory-secretory and somatic antigens from the Oestrus ovis larvae by SDS-PAGE and immunoblotting

Oestrus ovis is an economically important parasite of small ruminants and a zoonotic parasite with many reports of ophthalmomyiasis in human from Iran and other countries. The aim of the peresent study was the isolation and identification of excretory-secretory (ES) and somatic (S) antigens of O. ovis second and third stage larvae (L2, L3) collected from Arabi sheep breeds located in southwest of Iran. Positive sera were prepared by marking the sheep, taking blood sample and direct observation of the parasite in the head. Somatic antigens of the larvae (SL2, SL3) were prepared by sonication. Larval excretory-secretory antigens (ESL2, ESL3) were prepared by incubation the larvae in RPMI-1640 RPMI medium. Electrophoretic protein profiles of ESL2 two, ESL3 seven, SL2 eight, SL3 fifteen bands (from 79.0 to below 14.4 KDa) were shown. In immunoblotting with positive sera, four common bands in SL2 and SL3 at 58, 42.0, 29.0 and 28.0 kDa, one specific band in SL3 at 47.0 kDa and one band in ESL2, at 28.0 kDa, and three bands in ESL3 at 58.0, 42.0, 29.0 and 28.0 kDa were recognized. Among the profiles, the 28 kDa protein was the most common antigenic component. Nevertheless, the antigenic proteins 29, 58 kDa were a common protein in electrophoretic patterns of both S and ES proteins of L2 and L3 but, 42.0 kDa antigen the only one detected in immunoblot but not in S and ES protein profiles of the larvae. Therefore, the antigens 29.0, 42.0 and 58.0 kDa can be used for further studies of protective effects and serological diagnostic methods.

External ophthalmomyiasis presenting to an emergency department: corneal findings as a sign of Oestrus ovis

Purpose

This study aims to determine the frequency of opthalmyomyiasis externa and the ocular findings of disease in Southern Khorasan.

Methods

All patients referred to the emergency department of Valiaser hospital during the year 2011 with external ophthalmomyiasis were enrolled in this study. The diagnosis of external ophthalmomyiasis was made according to clinical findings and the presence of Oestrus ovis larvae.

Results

There were 18 cases of external ophthalmomyiasis in the emergency department of Valiaser hospital in 2011. Most cases had the common signs and symptoms of allergic conjunctivitis, except for three males who were referred with respective complaints of red eye, foreign body sensation, and swelling around the eyelids after contact injury the previous day; corneal infiltration was present in three cases. The visual acuity among the three cases that had peripheral corneal involvement was 20 / 30 in both eyes. The bulbar conjunctiva showed chemosis in all cases and a ropy pattern discharge that was clinically compatible with external ophthalmomyiasis. However, in one case, microscopic slit lamp examination did not show Oestrus ovis larvae.

Conclusions

The frequency of external ophthalmomyiasis was high in this region. Although external ophthalmomyiasis usually manifests as allergic conjunctivitis, coronary-like corneal infiltration may be considered in the differential diagnosis of external ophthalmomyiasis or toxic insult.

External ophthalmomyiasis: A case report

Ophthalmomyiasis is an infestation of the eye with larvae of most common sheep nasal botfly (Oestrus ovis). We describe a case of ophthalmomyiasis in a 50-year-old man who presented with ocular foreign body sensation, redness and tearing. The causative larvae were removed in the emergency room and sent to laboratory for identification. The patient symptoms improved after topical treatment with antibiotics-steroid combination therapy.

Unilateral acute conjunctivitis due to Oestrus ovis in a veterinary doctor

Myiasis is the infestation of tissues and organs of animals or man by fly larvae. We report a human case of external ophthalmomyiasis caused by the larvae of a sheep nasal botfly, Oestrus ovis, for the first time in a veterinary doctor. A 25-year-old veterinary doctor presented with severe symptoms of conjunctivitis. The larvae, 3 in number, were observed in the bulbar conjunctiva and the symptoms of the eye improved within a few hours of their removal. It is important for ophthalmologists to be aware of larval conjunctivitis as a significant possibility in the veterinary fraternity especially during the summer season.

External Ophthalmomyiasis which was Caused by Sheep Botfly (Oestrus ovis) Larva: A Report of 10 Cases

Myiasis is the infestation of the tissues and organs of animals or man by fly larvae. Ophthalmic myiasis has been reported from various world regions. In this study, we are presenting the clinical manifestations of external ophthalmomyiasis which was caused by the larvae of the sheep nasal botfly, Oestrus ovis, in 10 patients in the Tirunelveli and the Tuticorin districts of Tamil Nadu state India. All the patients were farmers, who worked in close contact with sheep and goats. All the patients presented with severe conjunctivitis. The larvae were observed in the bulbar conjunctiva and following their removal, the symptom of eye inflammation improved in a few hours.

Ophthalmomyiasis Externa: Case Report of the Clinicopathologic Features

Ophthalmomyiasis externa is the infestation of the superficial external ocular structures by fly larvae. This is a particularly rare condition, which has nevertheless been reported in several countries worldwide. Presented herein are the clinicopathologic features of ophthalmomyiasis externa which occurred in an adult patient. The patient responded well to treatment following thorough ophthalmological examination and prompt diagnosis.

Oestrus ovis as a Cause of Red Eye in Aljabal Algharbi, Libya

Purpose:

To study the common presenting signs of external ophthalmomyiasis caused by Oestrus ovis larvae in Aljabal Algharbi province, Libya.

Materials and Methods:

A prospective non- comparative study was conducted from September 2009 to July 2010 at the Gharian outpatient clinic, Gharian, Aljabal Algharbi, Libya. The common presenting features of patients with external ophthalmomyiasis and data on the organism that caused the disease were collected.

Results:

Twenty one cases diagnosed with external ophthalmomyiasis were recorded. There were fourteen males (66.67%) and seven females (33.33%) in the cohort. The mean age was 14.29 ± 3.46 years (range, 8 years to 22 years: males; 13.39 ± 3.03 years and females; 16.67 ± 3.75 years). The main complaint was redness (100.00%), itching (71.43%) and tearing (57.14%). Twelve patients (57.14%) were from rural areas and 9 patients (42.9%) were from urban areas. The causative organism was found to be first instar of Oestrus ovis larvae.

Conclusion:

External ophthalmomyiasis caused by Oestrus ovis can cause red eye in patients from Aljabal Algharbi, Libya and requires careful examination to ensure early diagnosis and proper treatment.

Ophthalmomyiasis externa caused by Oestrus ovis

A 50-year-old male presented with foreign body sensation, pain, and redness in left eye. Slit-lamp biomicroscopy revealed tiny larvae crawling around the conjunctival sac. The larvae, numbering 13, were mechanically removed under topical anesthesia and identified under light microscope as first-stage larvae of Oestrus ovis causing ophthalmomyiasis externa.

Vidi, vini, vinci: External ophthalmomyiasis infection that occurred, and was diagnosed and treated in a single day: A rare case report

Ophthalmomyiasis is an infestation of eye with larvae or maggots of certain flies. Oestrus ovis (sheep nasal botfly) belonging to family Oestridae is the most common cause of human myiasis. We describe here an acute presentation of a case of external ophthalmomyiasis, i.e., infestation of conjunctiva due to first instar larvae of Oestrus ovis. In this case report the occurrence, diagnosis and treatment all took place in the setting of a single day. Prompt treatment by removal of larvae mechanically followed by instillation of antibiotic and steroid eye drops helped to prevent serious complications. The taxonomic identification of fly is also important as some fly species are capable of penetrating deeper tissues of eyes, which is sight threatening.

External ophthalmomyiasis caused by Oestrus ovis: a rare case report from India

Myiasis of different organs has been reported off and on from various regions in the world. We report a human case of external ophthalmomyiasis caused by the larvae of a sheep nasal botfly, Oestrus ovis, for the first time from Meerut city in Western Uttar Pradesh, India. A 25-year-old farmer presented with severe symptoms of conjunctivitis. The larvae, 3 in number, were observed in the bulbar conjunctiva, and following removal the symptoms of eye inflammation improved within a few hours.