Identificación de larvas productoras de miasis obtenidas del cepario de la Universidad Colegio Mayor de Cundinamarca con importancia en salud pública / Identification of Myasis-producing Larvae from the Universidad Colegio Mayor de Cundinamarca

Resumen Las miasis son infestaciones parasitarias en humanos y animales causadas por estadios larvarios de moscas; son de distribución mundial y son una enfermedad frecuente en nuestro medio. En la literatura solo existen algunos casos reportados; por lo cual, su verdadera incidencia es difícil de establecer debido al sub-registro y ausencia de tipificación de larvas. Objetivo. Identificar, clasificar y caracterizar morfológicamente las larvas causantes de miasis como base para futuras aplicaciones e intervenciones en salud pública. Materiales y métodos. Se analizaron 262 larvas obtenidas del cepario de la Universidad Colegio Mayor de Cundinamarca que se encontraban almacenadas sin ningún tipo de identificación, organización e historia. Resultados. Se realizó la identificación con estereoscopio y claves dicotómicas de las familias Cuterebridae, Oestridae y Calliphoridae. Las especies encontradas son asociadas a diferentes tipos de miasis humana y animal, entre ellas; Dermatobia hominis, Dermatobia cyaniventris, Oestrus ovis, Cochliomyia hominivorax y Lucilia sp. Discusión. Las formas más comunes de este parasitismo son cavitarias y forunculares; causadas por Dermatobia hominis y Cochliomyia hominivorax, sin embargo, éstas no son de reporte obligatorio ante los servicios médicos humanos. Por lo tanto, es indispensable la información y capacitación de profesionales de la salud para la correcta conservación, identificación y reporte de las larvas extirpadas en pacientes con miasis, hasta el punto de ser considerada una práctica de rutina en el diagnóstico clínico.

Abstract Myiasis is the parasitic infestation of the body in humans and animals caused by larval stages of flies; such diseases are worldwide distributed and they are frequent in our environment. In the literature, there are only a few reports; therefore, its real incidence is difficult to be established due to sub-recorded cases and absence of larval typing. Objective. To identify, classify and morphologically characterize myasis-producing larvae of importance in public health. Material and methods. 262 larvae were analysed, obtained from the Universidad Colegio Mayor de Cundinamarca that were stored without any identification, organization and history. Results. Larvae were identified using a stereomicroscope and morphology was based on dichotomous keys of the Cuterebridae, Oestridae and Calliphoridae families. The species found are associated with different types of myiasis, including; Dermatobia hominis, D. cyaniventris, Oestrus ovis, Cochliomyia hominivorax, C. macellaria and Lucilia spp. Discussion. As a conclusion, we found that cavitary and foruncular were the most common forms of this parasitism in the collection from the Universidad Colegio Mayor de Cundinamarca. and that Dermatobia hominis and Cochliomyia hominivorax were the main involved species; however, these are not mandatory reporting species for medical services. Therefore, generating information about preservation, identification and recording of myasis-producing larvae, as well as training of professionals in public health might be considered as a routine practice for an accurate clinical diagnosis.

Oestrose: uma parasitose emergente em pequenos ruminantes no Nordeste do Brasil / Nasal bot: an emerging parasitic disease in small ruminants in the Brazilian Northeast

No período de janeiro de 2011 a dezembro de 2014 foram diagnosticados 9 surtos (A, B, C, D, E, F, G, H e I) de Oestrus ovis em pequenos ruminantes no estado da Bahia. No surto A obteve-se 0,5% (1/200); B 2,2% (2/90); C 0,8% (1/120); D 2% (2/100); E 1% (1/100); F 3% (1/33); G 0,6% (1/150); H 2,5% (5/200); I com 11,4% (8/70) em ovinos e 5% (2/40) em caprinos. Os sinais clínicos associados ao parasitismo pelas larvas nos surtos foram respiração ruidosa, espirro seguido de secreção nasal catarral, inquietação, movimentação excessiva da cabeça e andar em círculo. Macroscopicamente havia nos seios e conchas nasais hiperemia, edema da mucosa e presença de larvas. Todas as larvas coletadas dos cornetos e conchas nasais variavam desde o primeiro ao terceiro estágio de desenvolvimento. Algumas larvas L3 coletadas nas necropsias foram incubadas e o imago obtido das pupas mediram aproximadamente 10mm de cor acinzentada e abdômen escurecido. Realizada análise descritiva das condições climáticas, ano e positividade de casos de oestrose, demonstrou que a ocorrência tem tendência de crescimento com os anos (p˂0,001) e que houve casos com menor média de temperatura mínima (p˂0,001), possibilitando o desenvolvimento da mosca de O. ovis, demonstrando que houve a introdução da mosca enTtre o rebanho de ovinos e caprinos do estado da Bahia, e que as condições climáticas são ideais para perpetuação da espécie.(AU)

From January 2011 to December 2014 were diagnosed 9 outbreaks of Oestrus ovis infection in small ruminants (Outbreaks A-I) in the State of Bahia. The incidence of oestrosis in sheep in outbreak A was 0.5% (1/200), in B 2.2% (2/90), in C 0.8% (1/120), in D 2% (2/100), in E 1% (1/100), in F 3% (1/33), in G 0.6% (1/150), in H 2.5% (5/200), and in I 11.42% (8/70), and 5% (2/40) in goats. Clinical signs associated with parasitism were wheezing, sneezing followed by catarrhal nasal secretion, some restlessness, excessive head movement and walking in circles. The breasts and turbinates were hyperemic, with mucosal edema and presence of O. ovis larvae. All larvae collected from the turbinates ranged from the first to the third stage of development. Some L3 larvae collected at necropsy were incubated and the gray colored Imago with dark abdomen obtained from the pupae measured about 10mm. A descriptive analysis of the climatic conditions was carried out; in the year of investigation the incidence of O. ovis infection has grown (p<0.001), and the lowest mean minimum temperature (p<0.001) caused the development the O. ovis fly, so that there was an introduction of an increased number of these flies into the sheep and goat flocks in state of Bahia with the ideal climatic conditions for their perpetuation.(AU)

Doenças da cavidade nasal em pequenos ruminantes no Distrito Federal e no Estado de Goiás / Nasal cavity diseases of small ruminants in Federal District and Goiás State, Brazil

As enfermidades que acometem a cavidade nasal de pequenos ruminantes podem causar prejuízos aos rebanhos de ovinos e caprinos na região central do Brasil. Foi realizado estudo retrospectivo dos laudos de necropsia do Laboratório de Patologia Veterinária da Universidade de Brasília (LPV-UnB) nos anos de 2003 a 2014 para verificar a ocorrência das doenças que acometeram a cavidade nasal de pequenos ruminantes. Foram analisados 463 protocolos de ovinos e 75 de caprinos totalizando 538 casos. Seis ovinos (6/463 1,29%) foram necropsiados com rinite granulomatosa micótica ou oomicótica e 22 animais do estudo (22/538; 4,08%) tiveram o diagnóstico de oestrose, sendo 86,36% ovinos e 13,64% caprinos. As rinites piogranulomatosas em ovinos ocorreram em áreas alagadas, com abundante material vegetal em decomposição. Os ovinos com pitiose rinofacial apresentaram como principais alterações aumento de volume na região nasal devido a extensas lesões granulomatosas associadas a necrose tecidual, caracterizadas por inúmeros macrófagos e polimorfonucleares circundando centros necróticos contendo o agente envolto por reação de Splendore-Hoeppli. Os ovinos com conidiobolomicose exibiram extensas áreas de necrose e inflamação piogranulomatosa, associadas à presença de hifas fúngicas na nasofaringe e também na região peribulbar e exoftalmia. A maioria dos animais com oestrose não apresentou alterações clínico-patológicas significativas, apesar de serem encontradas larvas principalmente nos seios e conchas nasais, traqueia e seio paranasal. A importância dessas enfermidades ainda é pouco conhecida na região, sendo de grande relevância que as condições clínico-patológicas e epidemiológicas sejam elucidadas para o diagnóstico, o controle e a prevenção, para evitar a expansão e prejuízos para os rebanhos...

Nasal cavity diseases that affect small ruminants can cause losses to sheep and goat herds in Central Brazil. A retrospective study of the University of Brasilia´s Veterinary Pathology Laboratory autopsy reports from 2003 to 2014 was conducted to verify the occurrence of small ruminants nasal cavity diseases. Six necropsied sheep (6/463 1.29%) showed mycotic or oomicotic granulomatous rhinitis and 22 animals (22/538, 4.08%) presented oestrosis diagnosis, affecting 86.36% of sheep and 13.64% of goats. The pyogranulomatous rhinitis in sheep occurred in flooded areas with abundant plant material decomposing. Rhinofacial pythiosis infection in animals showed as major changes swelling in the nasal region due to extensive granulomatous lesions associated with tissue necrosis, characterized by numerous macrophages and polymorphonuclear cells surrounding necrotic centers containing the agent surrounded by Splendore-Hoeppli reaction. Sheep with conidiobolomycosis showed extensive areas of necrosis and pyogranulomatous inflammation associated with fungal hyphae, localized in the nasopharynx and also in peribulbar region and exophthalmia. Most animals with oestrosis showed no significant clinical and pathological changes, even with the presence of larvae mainly in the sinuses and nasal turbinates, trachea and paranasal sinus. The importance of such diseases is still unknown in the region, and the knowledge of the clinical-pathological and epidemiological conditions is of great relevance for the diagnosis, control and prevention to avoid the expansion and losses to livestock...

Oestrus ovis infection of grazing sheep during summer in southern Chile

Oestrus ovis is a botfly whose larvae cause nasal myiasis, an environmental-dependent disease in small ruminants, generating acute and chronic injuries in the cranial cavities of sheep. Chile is a country of the southernmost worldwide distribution of this parasite, and there is few information about. Whence, the objective of this study was to approximate the epidemiological situation of O. ovis infection in Chilean sheep. From December 2009 to March 2010, a total of 87 samples were obtained by necropsy for skull inspection. The larvae were collected, and microscopically identified. The prevalence in the sampled sheep was 60.9%. From those that were infected, 85.7% (18/21) of sheep were 1 to 3 years old, constituting the stratum with the highest prevalence. The difference of infection in females and males was not significant. The high risk of infection seems to be dependent upon the environmental conditions of this southern region, especially during summer when the first larval stage (L1) could be found as the evidence. Therefore, the disease should be considered as a significant problem for this kind of livestock production.

Occurrences of Oestrus ovis parasitism in necropsied sheep in the Umuarama microregion, Paraná, Brazil / Ocorrência de parasitismo por Oestrus ovis em ovinos necropsiados da microrregião de Umuarama - Paraná, Brasil

Between January 2007 and September 2013, 71 sheep belonging to 12 farms in the Umuarama microregion, State of Paraná, were evaluated regarding presence of Oestrus ovis larvae, during necropsies. The farms from which these animals originated were visited and the owners and employees were interviewed. Occurrences of O. ovis parasitism in sheep were diagnosed for the first time on this microregion. Of the 71 animals, 12 (16.9%) were parasitized by O. ovis, with mean intensity of 2.25 larvae per infested head (1 to 8 larvae/infested head). There was a high correlation (0.81, p=0.0346) between the number of larvae and the macroscopic lesions observed in these animals nasal cavities, such that sheep with more than 3 larvae may contain mucupurulent secretions or epistaxis. From the interviews conducted, it was found that all the farm owners were applying chemical parasite control methods (helminths and/or O. ovis), administered to all animals in the herds every 30 days (91.6% of the producers), using derivatives of macrocyclic lactones and/or benzimidazoles/imidazothiazoles. Further studies need to be conducted in this particular region, in an attempt to elucidate the prevalence of O. ovis parasitism in herds.

De janeiro de 2007 a setembro de 2013, foram avaliados, durante a necropsia, 71 ovinos pertencentes a 12 propriedades rurais da microrregião de Umuarama, Paraná, Brasil, quanto à presença de larvas de Oestrus ovis. Entre outubro e dezembro de 2013, as 12 propriedades de onde os animais eram provenientes foram visitadas, e os proprietários e funcionários foram entrevistados. A ocorrência do parasitismo por O. ovis em ovinos foi constatada pela primeira vez em propriedades rurais da microrregião de Umuarama, Estado do Paraná. Dos 71 animais, 12 (16,9%) estavam parasitados por O. ovis, com intensidade média de parasitismo de 2,25 larvas por cabeça infestada (1 a 8 larvas). Foi possível verificar correlação elevada (0,81, p=0,0346) apenas entre o número de larvas versus lesões macroscópicas observadas na cavidade nasal desses animais, de modo que ovinos com mais de 3 larvas continham secreção mucopurulenta ou epistaxe na cavidade. Quando da entrevista constatou-se que todos os proprietários fazem controle químico contra parasitas (helmintos e/ou O. ovis) e esse. controle é feito a cada 30 dias por 91,6% dos produtores, que utilizam derivados de lactonas macrocíclicas e/ou benzimidazóis/imidatiazóis. Futuros estudos ainda precisam ser realizados nesta região, na tentativa de elucidar a prevalência de parasitismo por O. ovis nos rebanhos.

Human ophthalmomyiasis externa caused by the sheep botfly Oestrus ovis: A case report from Karachi, Pakistan

Ocular myiasis due to Oestrus ovis larvae infestation is an eye infection in humans. A case of ophthalmomyiasis externa in a young male from Karachi, Pakistan in winter (December 2012), without history of close proximity to domestic animals or visit to any rural area was reported. The condition is self-limiting and the disease is confined to the conjunctiva. The eye was locally anesthetized and washed with 5% povidine iodine solution. A total number of 27 first instar larvae of Oestrus ovis were removed with fine forceps. The patient received 0.5% moxifloxacin and diclofenac eye drops for one week. His eye was examined after one day, one week and one month and the recovery status was favorable. The present case raise the awareness among ophthalmologists regarding larval conjunctivitis as one of the causes of conjunctivitis and it can occur throughout the year in any season including winter. Moreover, it can occurr in any area either rural or urban with or without close proximity to domestic animals especially in subtropical regions with high parasitic burden.

Human ophthalmomyiasis externa caused by the sheep botfly Oestrus ovis：a case report from Karachi, Pakistan

Ocular myiasis due to Oestrus ovis larvae infestation is an eye infection in humans. A case of ophthalmomyiasis externa in a young male from Karachi, Pakistan in winter (December 2012), without history of close proximity to domestic animals or visit to any rural area was reported. The condition is self-limiting and the disease is confined to the conjunctiva. The eye was locally anesthetized and washed with 5% povidine iodine solution. A total number of 27 first instar larvae of Oestrus ovis were removed with fine forceps. The patient received 0.5% moxifloxacin and diclofenac eye drops for one week. His eye was examined after one day, one week and one month and the recovery status was favorable. The present case raise the awareness among ophthalmologists regarding larval conjunctivitis as one of the causes of conjunctivitis and it can occur throughout the year in any season including winter. Moreover, it can occurr in any area either rural or urban with or without close proximity to domestic animals especially in subtropical regions with high parasitic burden.

A case of nasal myiasis due to Oestrus ovis (Diptera: Oestridae) in a llama (Lama glama) / Um caso de miíase nasal devido a Oestrus ovis (Diptera: Oestridae) em lhama (Lama glama)

Infection by the larval form of Oestrus ovis (sheep bot fly) is common in many areas of Peru. This is an obligate parasite of sheep and goats, and it is the cause of oestrosis, or nasal myiasis, which can lead to severe clinical manifestations in livestock. A case of myiasis caused by O. ovis in a llama (Lama glama) in Cuzco, Peru, is reported here. This llama presented with respiratory distress and died due to bilateral hemorrhagic pneumonia. During the necropsy, six intact dipterous larvae were recovered from the nasal fossae and cranial sinuses being identified as O. ovis. This is the first report of nasal myiasis in llamas due to O. ovis in Peru.

Infecção pela forma larval de Oestrus ovis (bicho da cabeça) é comum em muitas regiões do Peru. Este é um parasito obrigatório de ovinos e caprinos, e é a causa de oestrose ou miíase nasal, que pode conduzir à manifestações clínicas graves nos animais. Relatou-se um caso de miíase causada por O. ovis numa lhama (Lama glama) em Cuzco, Peru. A lhama apresentou insuficiência respiratória e morreu de pneumonia bilateral hemorrágica. Durante a necropsia, seis larvas intactas do díptero foram recuperadas das fossas nasais e dos seios cranianos e identificadas como O. ovis. Este é o primeiro relato de miíase nasal em lhamas por O. ovis no Peru.

Red eye: Rule out Ophthalmomyiasis too.

Ophthalmomyiasis is the infestation of human eye by the larvae of certain flies. Sheep botfly commonly manifests as Ophthalmomyiasis externa when there is conjunctival involvement or rarely as Opthalmomyiasis interna when there is larval penetration into the eyeball. It appears to be more common than what has been indicated by previously published reports. We present a report of seven cases of Ophthalmomyiasis by Oestrus ovis, from central India who presented with features of conjunctivitis varying between mild to severe. The larvae were seen in bulbar and palpebral conjunctiva and also entangled in lashes with discharge. Since the larvae are photophobic, it is prudent to look for them in the fornices and also in discharge. Prompt removal of the larvae from the conjunctiva helps in relieving the symptoms and also prevents serious complications. Taxonomic identification of the species is important to estimate the risk of globe penetration by the larvae.

Prevalence of Oestrus ovis (Diptera: Oestridae) in sheep from the São Paulo Central region, Brazil / Prevalência de Oestrus ovis (Diptera: Oestridae) em ovinos da região Central de São Paulo, Brasil

The heads of 139 slaughtered sheep were examined with the aim of determining Oestrus ovis prevalence and infestation intensity in the central region of the State of São Paulo, Brazil. Heads from slaughtered sheep were examined and the first (L1), second (L2) and third (L3) O. ovis larval instars were recovered from the nasal and sinus cavities. O. ovis larvae were detected in 13.7% of the sheep analyzed. The monthly mean intensity of infestation ranged from 1 to 10.2 larvae per infested head, with general mean intensity of 4.5 larvae/infested head. Of the total of 85 larvae, 21.2% were L1, 37.6% L2 and 41.2% L3. In conclusion, all different O. ovis larvae instars were recovered from slaughtered animals, which demonstrates the existence of favorable climatic conditions for the fly activity and larval development of O. ovis in sheep raised in the Central region of the State of São Paulo.

Com o objetivo de determinar a prevalência e intensidade de infestação por larvas de Oestrus ovis na região Central do Estado de São Paulo, 139 cabeças de ovinos obtidas de um abatedouro foram examinadas. As larvas O. ovis foram recuperadas da cavidade nasal e seios frontais, identificadas de acordo com o estádio larval e quantificadas. As larvas de O. ovis foram detectadas em 13,7% das cabeças examinadas e a intensidade média mensal de infestação variou entre 1 a 10,2 larvas/cabeça infestada, com média geral de 4,5 larvas/cabeça infestada. Do total de 85 larvas recuperadas, 21,2% eram larvas de primeiro estádio (L1), 37,6% de segundo (L2) e 41,2% de terceiro (L3). Em conclusão, todos os diferentes instares larvais de O. ovis foram recuperados de animais abatidos, o que demonstra a existência de condições climáticas favoráveis para a atividade da mosca bem como o desenvolvimento larval em ovinos criados na região Central do Estado de São Paulo.

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.

Epidemiology of Oestrus ovis (Diptera: Oestridae) in sheep in Botucatu, State of São Paulo / Epidemiologia de Oestrus ovis (Diptera: Oestridae) em ovinos em Botucatu, São Paulo

The seasonal factors that influence Oestrus ovis infestation in sheep were determined in Botucatu, State of São Paulo, Southwestern Brazil, from April 2008 to March 2011. Two tracer lambs were monthly exposed to natural infestation by O. ovis larvae for 28 consecutive days, by grazing with a sheep flock. Tracer animals were then euthanized and the larvae of O. ovis recovered from nasal and sinus cavities. Of the 72 tracer lambs, 50% were infested with O. ovis larvae and the mean intensity of infestation per head infested was 16.8 larvae, with an average of 7.8 L1, 5.3 L2 and 3.7 L3. O. ovis larvae were present during the four seasons of the year, but the mean larval burden was significantly higher during the spring and summer months, compared to winter (P < 0.05). The highest rate of larvae recovery coincided with mean temperatures between 20 °C and 25 °C and air relative humidity around 70%. Results suggest that evolution and development of O. ovis practically occurs throughout the entire year, with larval infestation especially frequent during the spring and summer months.(AU)

Os fatores sazonais que influenciam a infestação por larvas de Oestrus ovis, foram determinados no período de abril de 2008 a março de 2011, em ovinos criados em Botucatu, São Paulo, região Sudeste do Brasil. Mensalmente, dois cordeiros traçadores permaneceram em pastejo com um rebanho ovino durante 28 dias consecutivos, expostos à infestação natural por larvas de O. ovis. Em seguida, os cordeiros foram sacrificados, e as larvas de O. ovis recuperadas da cavidade nasal e seios frontais. Dos 72 cordeiros traçadores, 50% estavam infestados por larvas de O. ovis, com intensidade média de infestação de 16,8 larvas/cabeça infestada, com média de 7,8 L1, 5,3 L2 e 3,7 L3. As larvas de O. ovis foram recuperadas durante as quatro estações do ano, mas o número médio de larvas foi significativamente superior durante os meses de primavera e verão comparado aos meses de inverno (P < 0,05). A maior taxa de recuperação larval coincidiu com temperaturas médias entre 20 °C e 25 °C e umidade relativa do ar por volta de 70%. Os resultados sugerem que a evolução e desenvolvimento de O. ovis ocorre praticamente durante o ano inteiro, mas a infestação é mais frequente nos meses de primavera e verão.(AU)

Surto de Oestrus ovis em ovinos em Mato Grosso / Outbreak of Oestrus ovis in sheep in Mato Grosso, Brazil

Oestrus ovis é um parasito cosmopolita que pode acometer ovinos e caprinos. A fase parasitária inicia-se após as fêmeas adultas depositarem suas larvas nas narinas dos hospedeiros. O objetivo deste trabalho foi de descrever os aspectos clínicos, epidemiológicos, macroscópicos e microscópicos de um surto de oestrose em ovinos no estado de Mato Grosso. Os principais sinais clínicos observados foram espirros e descarga nasal. Macroscopicamente havia hiperemia e edema da mucosa nasal. Os achados microscópicos eram caracterizados por hiperemia e edema moderado a acentuado e difuso, associados a infiltrado leve a moderado predominante de mastócitos e eosinófilos na submucosa. Embora a doença fosse observada em um grande número de animais a mortalidade observada nos surtos ocorreu devido à infestação por Haemonchus contortus e pneumonia.

Oestrus ovis is a cosmopolitan agent of myiasis in sheep and goats. The parasitic phase begins after adult females deposit first stage larvae into the nostrils of hosts. The aim of this study was to describe the epidemiological data, clinical signs, gross and microscopical findings of an outbreak of O. ovis myiasis in sheep in state of Mato Grosso. Sneezing and nasal discharges was the major clinical signs in infected sheep. The main gross findings include hyperemia and oedema of the nasal mucosa. At the microscopic exam there was moderate infiltration of mast cells and eosinophils in the nasal mucosa with moderate to severe oedema and hyperemia. Although affecting a large number of sheep, the mortality occurred due to other causes such as Haemonchus contortus infection and pneumonia.

Oestrus ovis ophthalmomyiasis with keratitis.

A 35-year-old male patient presented with complaints of redness, swelling around the eyelids, watering, and irritation in the right eye. At presentation his best-corrected visual acuity was 20/20 partial in the right eye. The tarsal conjunctiva of the upper eyelid showed injection with pseudomembrane. Underneath the pseudomembrane we noticed four motile larvae. The cornea showed an irregular cobweb-like mucous plaque adherent to the epithelium, with a clear stroma. The pseudomembrane was easily peeled-off under topical anaesthesia. The organisms were removed and identified as Oestrus ovis. Three days later the patient was comfortable and his visual acuity was 20/20 in the right eye.

Ophthalmomyiasis: Three cases from North India.

Three cases of external ophthalmomyiasis are reported here. The larvae were identified to be Oestrus ovis in two cases and Cochliomyia hominivorax in one. Two of the patients were immunocompetent while one was undergoing treatment for squamous cell carcinoma of eyelid. In the latter myiasis led to complete destruction of the eye.

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.