Case Report: Outbreak of Nosocomial Myiasis by Cochliomyia macellaria (Diptera, Calliphoridae) in a Hospital in Colima, Mexico.

Myiasis in humans is a disease caused by larvae of various fly families. It mainly occurs in communities with poor sanitation and low socioeconomic status. Meanwhile intrahospital or nosocomial myiasis represents a rare phenomenon but is of relevance to public health. Here, we report an outbreak of myiasis caused by Cochliomyia macellaria in five patients hospitalized for several diseases at the Service of Internal Medicine of the Hospital Regional Universitario de Colima, Mexico during June and July 2021. Three patients were males and two were females, aged 37 to 83 years. All were affected by myiasis caused by larvae of the fly C. macellaria. Three patients underwent invasive mechanical ventilation; one had cutaneous basal cell cancer and one had advanced diabetic foot. This event occurred after 4 days of hospitalization and in the same hospital pavilion. Two patients died, and the others were discharged after treatment with antibiotics and ivermectin. We believe that this nosocomial cluster represents a more frequent phenomenon than reported in tropical countries, where authorities should pay attention to its timely detection, especially in vulnerable populations.

Oral myiasis affecting paediatric patients: a systematic review.

INTRODUCTION: Oral myiasis is a rare condition caused by Dipteran larvae that feed on living or dead tissues, ingested food or body fluids. It affects immunocompromised individuals with low socioeconomic status or those unable to maintain proper hygiene. Cases of oral myiasis are scarce but debilitating in children. We conducted a systematic review to understand the nature of disease, its causative factors, treatment and ways to prevent the occurrence of this condition among children. METHODOLOGY: The review was carried out in accordance with Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. A systematic electronic literature search was conducted on major databases using keywords in combination with Boolean Operators. Manuscripts discussing cases of oral myiasis in paediatric patients were included in the review. RESULTS: The exhaustive literature search and evaluation of full texts revealed 32 studies that fulfilled the inclusion criteria. A total of 68 cases of oral myiasis were reported from 2 to 16 years of children, majorly involving gingiva of maxillary anterior region and palate. CONCLUSION: The dreadful condition of myiasis can be prevented by decreasing the number of flies, maintenance of good hygiene and by educating the susceptible population. Affected children must be managed by following proper treatment regimens.

Children hospitalized for myiasis in a reference center in Uruguay / Niños hospitalizados por miasis en un centro de referencia de Uruguay

Abstract Background: Myiasis is an emerging disease caused by tissue invasion of dipteran larvae. In Uruguay, Cochliomyia hominivorax and Dermatobia hominis are the most frequent species. This study aimed to describe the epidemiological and clinical characteristics and the follow-up of children < 15 years hospitalized for myiasis in a reference center in Uruguay between 2010 and 2019. Methods: We conducted a descriptive and retrospective study by reviewing medical records. We analyzed the following variables: age, sex, comorbidities, origin, the month at admission, clinical manifestations, other parasitoses, treatments, complications, and larva species identified. Results: We found 63 hospitalized children: median age of 7 years (1 month-14 years), 68% of females. We detected risk comorbidities for myiasis (33%), of which chronic malnutrition was the most frequent (n = 6); 84% were from the south of the country; 76% were hospitalized during the summer. Superficial and multiple cutaneous involvements were found in 86%: of the scalp 50, furunculoid type 51, secondary to C. hominivorax 98.4%, and to D. hominis in 1.6%. As treatments, larval extraction was detected in all of them, surgical in 22%. Asphyctic products for parasites were applied in 94%, ether in 49. Antimicrobials were prescribed in 95%; cephradine and ivermectin were the most frequent. About 51% presented infectious complications: impetigo was found in 29, cellulitis in 2, and abscess in 1. Conclusions: Myiasis predominantly affected healthy schoolchildren during the summer months and was frequently associated with ectoparasites. Superficial infestation of the furuncle-like scalp by C. hominivorax was the most frequent form. Infectious complications motivated hospitalizations.

Resumen Introducción: La miasis es una enfermedad emergente producida por la invasión tisular por larvas de dípteros. En Uruguay, Cochliomyia hominivorax y Dermatobia hominis son las especies más frecuentes. El objetivo de este estudio fue describir las características epidemiológicas y clínicas, y el seguimiento, de niños menores de 15 años hospitalizados por miasis en un centro de referencia del Uruguay entre 2010 y 2019. Métodos: Se llevó a cabo un estudio descriptivo y retrospectivo mediante la revisión de las historias clínicas. Se analizaron las siguientes variables: edad, sexo, comorbilidad, procedencia, mes al ingreso, cuadro clínico, otras parasitosis, tratamientos, complicaciones y especie de larva identificada. Resultados: Se encontraron 63 casos de niños hospitalizados, con una mediana de edad de 7 años (rango: 1 mes a 14 años) y el 68% de sexo femenino. Se identificó comorbilidad de riesgo para miasis (33%), siendo la desnutrición crónica la más frecuente (n = 6). El 84% eran procedentes del sur del país y el 76% fueron hospitalizados en los meses estivales. Se encontró afectación cutánea superficial y múltiple en el 86%: de cuero cabelludo en 50, de tipo forunculoide en 51, secundaria a C. hominivorax en el 98.4% y a D. hominis en el 1.6%. Se realizó extracción larvaria en todos los casos, que fue quirúrgica en el 22%. Se aplicaron productos asfícticos para parásitos en el 94%, con éter en 49 niños. Se prescribieron antimicrobianos en el 95%; los más usados fueron cefradina e ivermectina. El 51% presentaron complicaciones infecciosas: 29 impétigo, 2 celulitis y 1 absceso. Conclusiones: La miasis afectó predominantemente a escolares sanos y durante los meses estivales, y se encontró frecuentemente asociada con ectoparasitosis. La infestación superficial del cuero cabelludo de tipo forunculoide por C. hominivorax fue la forma más frecuente. Las complicaciones infecciosas motivaron las hospitalizaciones.

Oftalmomiasis / Ophthalmomiasis

La oftalmomiasis es una enfermedad poco frecuente, causada por artrópodos; en este caso por la mosca adulta. Presentamos el caso de una paciente femenina, de 44 años de edad, con antecedentes de inmunosupresión severa secundaria a VIH, quien fue atendida en el Servicio de Oftalmología por molestia ocular. Presentaba un aumento de volumen circunscrito en conjuntiva que se extendía sobre la córnea nasal del ojo izquierdo, de aspecto blanco nacarado, deslustrado. Se le realizó exéresis de la lesión y crioterapia. Posteriormente se le aplicó colirio de mitomicina C. A los siete meses la paciente regresó a la consulta con un cuadro de complicación franca y severa de la lesión, con destrucción de los tejidos de la órbita y múltiples cavernas ocupadas por cientos de larvas de moscas(AU)

Ophthalmomiasis is a rare disease, caused by arthropods; in this case by the adult fly. We present the case of a 44-year-old female patient, with a history of severe immunosuppression secondary to HIV, who was treated at the Ophthalmology Service for ocular discomfort. She presented a circumscribed increase in volume in the conjunctiva that extended over the nasal cornea of ​​the left eye, with a pearly white, tarnished appearance. Excision of the lesion and cryotherapy were performed. Subsequently, mitomycin C eye drops were applied. Seven months later, the patient returned to the consultation with a frank and severe complication of the lesion, with destruction of the tissues of the orbit and multiple caverns occupied by hundreds of fly larvae(AU)

The Botfly, A Tropical Menace: A Distinctive Myiasis Caused by Dermatobia hominis.

Dermatobia hominis, also known as the human botfly, is native to tropical and subtropical Central and South America and seen in travelers from endemic to temperate regions including the United States and Europe. Cutaneous infestation botfly myiasis involves the development of D. hominis larvae in the skin and is common in tropical locations. The distinct appearance of a cutaneous D. hominis infestation facilitates early diagnosis and intervention where cases are common. However, the identification of D. hominis in temperate regions may prove challenging due to its rarity. D. hominis may be misdiagnosed as folliculitis, an epidermal cyst, or an embedded foreign object with secondary impetigo. One should have a heightened suspicion in someone returning from a vacation in an endemic area, such as Belize. Here we describe the presentation, differential diagnosis, and treatment and encourage enhanced preventative measures among tourists when visiting tropical and subtropical regions. Additionally, we propose a novel classification system for assessing the various stages of infestation and suggest that patients reporting travel to Latin America and experiencing pain disproportionate to an insect bite should lead physicians to consider myiasis caused by D. hominis.

Occurrence of Gasterophilus spp. in weanling foals in southern Brazil

The occurrence of gastrointestinal myiasis caused by Gasterophilus spp. larvae (Diptera: Oestridae) in adult horses has been widely characterized, however data on natural infestation in young foals have been lacking. This observation may be related to the absence of conclusive diagnosis in these individuals, most likely due to logistical or financial constraints. Gastric ulceration is a problem and a significant cause of morbidity in foals, particularly during the weaning stage; therefore, gasterophilosis should be included in the differential diagnosis. The primary purpose of this study was to determine the prevalence of gasterophilosis in 4- to 6-month-old weanling foals. Seventy-one healthy weanling foals were enrolled in the study. Physical assessment blood sampling and was completed in all foals before the commencement of the experiment. Gastroscopy examinations were performed under sedation (Detomidine 0.01 - 0.02 mg/kg) with a flexible endoscope inserted through nasogastric via. The lumen of the stomach was examined in order to search for botflies' larvae. Following gastroscopy, foals were classified into 2 groups based on the presence of Gasterophilus spp. larvae in their stomachs: 1) Infected and 2) Not Infected. Infected foals received a single dose of commercial trichlorfon and albendazole equine oral gel and were stalled for 24 h. The passed feces were thoroughly examined, searching for elimination of larvae. A total of 64% of the foals (n = 45/71) harbored Gasterophilus spp. larvae in the stomach. Mild hyperemia in the gastric mucosa was observed in the attachment sites of the parasites. Physical assessment and hematological parameters' data were analyzed with Shapiro-Wilk normality test. Comparison between groups for clinical signs, hematological parameters and Gasterophilus spp. infection rates were evaluated using the Kruskal-Wallis test or Student's t-test. Statistical significance was set at P < 0.05. There were no statistically significant variations in physical and hematological parameters between foals that were affected and those that were not infected. The larvae found in the feces were subjected to morphological examination, which confirmed the diagnosis of Gasterophilus intestinalis. No systemic clinical indications compatible with Gasterophilus spp. infestation were seen, as described in previous studies of horses infected with the parasite. No botfly eggs were observed in the hair of evaluated foals. During gastroscopy, mild hyperemic lesions in the gastric mucosa were observed in the larvae fixation sites. Although no changes in clinical or hematological parameters were noted, the confirmation of parasite presence is a cause for concern due to horses' tolerance for low infestation levels and poor diagnosis. Additionally, the presence of this myiasis in foals may be a significant stressor during the weaning period and should be included in the differential diagnosis of recurring abdominal pain. Furthermore, infected foals might be a reservoir for the parasite and, contribute to the elimination and spread of the larvae in the environment. Thus, inclusion of young horses in deworming protocols targeted to botfly larvae is needed. This is the first report of Gasterophilus intestinalis myiasis in foals in Brazil. Further research is necessary to fully understand the epidemiology and prevalence of this condition in young horses in Brazil, based on the findings of this study.(AU)

High morbidity cutaneous enzootic myiasis by Dermatobia hominis (Diptera: Oestridae) in sambar deer (Rusa unicolor).

This study describes the first known occurrence and treatment of enzootic cutaneous myiasis by Dermatobia hominis in a herd of sambar deer (Rusa unicolor). Sambar deer are clinically affected by enzootic cutaneous myiasis during the spring and summer in Rio de Janeiro, Brazil. Through direct inspection and clinicopathological evaluation in the herd with 80 R. unicolor, it was observed that infestation by D. hominis caused 100% morbidity. At histological exam, skin had eosinophilic and granulomatous chronic active severe necrohemorrhagic dermatitis associated with botfly and moderate surrounding fibroplasia. The systemic treatment with oral ivermectin at 0.08% was effective in 93.7% of deer with enzootic cutaneous myiasis after fourteen days. After treatment, the skin deer had eosinophilic and granulomatous chronic severe dermatitis associated with degenerated botfly and severe fibroplasia. Notable differences in leukocyte profile were observed between groups pre- and post-treatment. Decrease of relative values of neutrophils and eosinophils were significant in the treated deer group. An increase of relative values of monocytes was also confirmed in the treated group. Sambar deer was the only species affected by D. hominis, even though several other wild herbivores were kept in the same area. More studies are needed to elucidate the susceptibility of R. unicolor to D. hominis cutaneous infestations.

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.

DERMAL MYIASIS CAUSED BY THE FLESH FLY, PARASARCOPHAGA (LIOSARCOPHAGA) DUX (THOMSON, 1869) (DIPTERA: SARCOPHAGIDAE) AT THE SITE OF A MALIGNANT MELANOMA: A CASE REPORT.

Dermal myiasis due to the flesh fly has not been commonly reported in Thailand. A 64-year-old man came to the hospital with a 6-month history of a black tumor on the dorsum of the right great toe. The tumor was biopsied and determined to be a malignant melanoma. Second instar larvae were also seen in the wound and one larva was reared until the adult stage wherein it was identified as the flesh fly, Parasarcophaga (Liosarcophaga) dux (Thomson, 1869) (Diptera: Sarcophagidae). This case shows myiasis due to synanthropic sarcophagid flies occurs in Thailand and can occur in a malignant melanoma.

Distribución estacional de miasis mucocutánea. Nuestra experiencia / Seasonal distribution of mucocutaneousmyiasis. Our experience / Distribuição sazonal de miíase mucocutânea. A nossa experiencia

Introducción: la miasis es una lesión producida por larvas de mosca que infestan animales, de cuyos tejidos se alimentan en forma parasitaria. En nuestro servicio de otorrinolaringología tratamos frecuentemente pacientes con miasis mucocutáneas. El comprender la distribución estacional de esta patología podría ser una herramienta útil para la prevención de la misma. Métodos: Se valoraron las historias clínicas informatizadas del servicio de Otorrinolaringología del Hospital Federico Abete de Malvinas Argentinas, entre enero de 2013 y diciembre de 2015, utilizando como filtro la palabra “miasis”; de las cuales se analizaron las variables: mes de infestación, sitio anatómico comprometido, la edad, el género y la temperatura al momento de la consulta. Resultados: Se encontraron 27 pacientes. La edad promedio fue de 42 años. Quince pacientes masculinos y 12 femeninos. Sitio anatómico comprometido: conducto auditivo externo: 11; traqueostoma: 8; Sitio operatorio: 5; oído medio: 3. Todos fueron diagnosticados en las estaciones más cálidas. Conclusiones: Se observó la aparición de miasis en las estaciones más cálidas. Sería aconsejable tomar mayor cantidad de medidas preventivas durante estas épocas del año, para evitar los casos de infestación larvaria, cuando es posible.

Introduction: Myiasis refers to the damage caused by fly larvaes, which infest animals, including humans, and who feed in form parasitic of their dead or living tissue, causing tissue destruction. In our department of otolaryngology, we often treat patients with mucocutaneous myiasis. Understand the seasonal distribution of this disease could be a useful tool for preventing it. Method: Computerized medical records of Otolaryngology Service of Hospital Municipal Dr. Federico Abete of Malvinas Argentinas were valued, in the period between 2013 and 2015, it was used as a filter the word “myiasis”. Were found a series of 27 cases with diagnosis of mucocutaneous myiasis; of which were analyzed the variables: month of infestation, involved anatomic site, age and temperature at the time of medical consultation. Results: 27 patients were found. The average age was 42 years. 15 male patients and 12 female patients. Involved anatomic site: external auditory canal: 11; tracheostomy: 8; infestation surgical site: 5; middle ear: 3. All were diagnosed in the warmer seasons. Conclusions: The appearance of myiasis was observed in the warmer seasons. It would be advisable to take as many preventative measures during these times of the year to avoid cases of larval infestation, when possible.

Introdução: Miíase é uma lesão causada por larvas de moscas que infestam animais e dos que se alimentam de forma parasitária de seus tecidos. Em nosso departamento de otorrinolaringología tratamos muitas vezes pacientes com miíase mucocutânea. Compreender a distribuiçãos a zonal destado ença poderia ser uma ferramenta útil para evitar isso. Método: Forama valiados registros médicos computadorizados de Serviço de Otorrinolaringologia do Hospital Municipal Dr. Federico Abete de Malvinas Argentinas, no período entre 2013 e 2015, ele foi usado como filtro a palavra “miasis”. Foram encontradas uma série de 27 casos com diagnóstico de miíase mucocutânea; dos quais foram analisados as variáveis: mês de infestação, local anatómico en volvidos, idade e sexo dos pacientes; que foram comparados com os dados de temperatura do Servicio Meteorológico Nacional. Resultados: 27 pacientes foram encontrados. A idade média foi de 42 anos. 15 pacientes do sexo masculino e 12 do sexo feminino. Local anatômico envolvidos: canal auditivo externo: 11; traqueostomia: 8; infestação de sítio cirúrgico: 5; ouvido médio: 3. Todos foram diagnosticados nas estações mais quentes. Conclusões: O aparecimento de miíases foi observada nas estações mais quentes. Seria aconselhável tomar tantas medidas preventivas durante estas épocas do ano para evitar casos de infestação larval, quando possível.

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.

Miíases humanas: Atualidades para a prática clínica / Human myiasis: updates to the clinical practice

Miíase é uma infestação ectoparasitária, que tem as espécies Cochliomyia hominivorax, Dermatobia hominis e Cochliomyia macellaria como maiores destaques. Os principais fatores de risco são baixo nível socioeconômico, padrões inadequados de higiene, enfermidades psiquiátricas, diabetes mellitus, imunodepressão, etilismo, desnutrição e úlcera varicosa. Os autores abordam a importância epidemiológica da miíase humana em regiões endêmicas, discorrendo sobre manifestações clínicas, diagnóstico, tratamento e medidas profiláticas...

The myiasis consists of a parasitic infestation, the species having Cochliomyia hominivorax, Dermatobia hominis and Cochliomyia macellaria as most prominent. The main risk factors are low socioeconomic status, inadequate hygiene standards, psychiatric disease, diabetes mellitus, immunosuppression, alcoholism, malnutrition and varicose ulcer. There may be asymptomatic or systemic cases with serious complications. The purpose of this article is to address the epidemiological importance of human myiasis in endemic regions, discussing clinical manifestations, diagnosis, treatment and prophylactic measures...

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.

Primer reporte de miasis hospitalaria por Lucilia cuprina (Diptera: Calliphoridae) en Costa Rica / First report of nosocomial myiasis by Lucilia cuprina (Diptera: Calliphoridae) in Costa Rica

Introducción. Las miasis hospitalarias son entidades con una importancia manifiesta en salud pública. La documentación de este tipo de casos es escasa en la literatura biomédica regional y mundial. Objetivo. Informar un caso de miasis hospitalaria en Costa Rica, donde el agente etiológico implicado fue Lucilia cuprina (Diptera: Calliphoridae). Este caso de miasis hospitalaria figura como el primer informe para Latinoamérica asociado con este agente etiológico. Presentación del caso. Una paciente de 91 años de edad, con signos de inmunosupresión, afectación grave de la función pulmonar y asistencia respiratoria mecánica, presentó larvas en ambas fosas nasales al séptimo día después del ingreso hospitalario. Varios ejemplares fueron recolectados y procesados para su identificación. La identificación taxonómica de los ejemplares recolectados estableció que la especie de los muscomorfos correspondía a L. cuprina. Conclusión. El presente constituye el primer caso de miasis hospitalaria por L. cuprina en la literatura biomédica de Costa Rica y el primero registrado en Latinoamérica.

Introduction. Nosocomial myiases can be an important condition from a public health perspective. However, cases of this condition reported in regional and worldwide biomedical literature are scarce. Objective. A case of nosocomial myiasis is reported from Costa Rica, where the species involved was Lucilia cuprina (Diptera: Calliphoridae). Materials and methods. A 91-year-old patient with signs of immunosuppression, severe impairment of lung function, and mechanical ventilation presented larvae in both nostrils on the seventh day after admission. Five specimens were collected and processed for identification. Results. The taxonomic identification of the specimens established that the muscoid fly species was L. cuprina. Conclusion. This is the first case of nosocomial myiasis reported from Costa Rica and in Latin America for which the etiological agent is L. cuprina.

Parasitic infestations requiring surgical interventions.

Parasitic infestation is common in developing countries especially in Africa. Children are often more vulnerable to these infections. Many health problems result from these infestations, including malnutrition, iron-deficiency anemia, surgical morbidities, and even impaired cognitive function and educational achievement. Surgical intervention may be needed to treat serious complications caused by some of these parasites. Amoebic colitis and liver abscess caused by protozoan infections; intestinal obstruction, biliary infestation with cholangitis and liver abscess, and pancreatitis caused by Ascaris lumbricoides; biliary obstruction caused by Faschiola; hepatic and pulmonary hydatid cysts caused by Echinococcus granulosus and multilocularis are examples. Expenditure of medical care of affected children may cause a great burden on many African governments, which are already suffering from economic instability. The clinical presentation, investigation, and management of some parasitic infestations of surgical relevance in African children are discussed in this article.

Myiasis.

Myiasis is defined as the infestation of live vertebrates (humans and/or animals) with dipterous larvae. In mammals (including humans), dipterous larvae can feed on the host's living or dead tissue, liquid body substance, or ingested food and cause a broad range of infestations depending on the body location and the relationship of the larvae with the host. In this review, we deeply discuss myiasis as a worldwide infestation with different agents and with its broad scenario of clinical manifestations as well as diagnosis techniques and treatment.

Primer reporte de pseudomiasis intestinal humana por Eristalis tenax (Diptera, Syrphidae) en zona semiárida urbana del estado Falcón, Venezuela / First report of human intestinal pseudomiasis by Eristalis tenax (Diptera, Syrphidae) in urban semiarid area from Falcon state, Venezuela

Pseudomiasis es el término empleado cuando se considera que las larvas y/o huevos de moscas se adquieren accidentalmente per os y atraviesan con inmediatez a lo largo del tracto digestivo. Se documenta un caso de una pseudomiasis intestinal por larvas de Eristalis tenax (Diptera: Syrphidae) en una paciente femenina de 39 años de edad, proveniente de un sector periférico de la ciudad de Coro, estado Falcón, Venezuela. La paciente observó inmediatamente la presencia de la larva viva en sus heces. Aunque refirió sufrir eventualmente de cólicos, al examen físico se presentó normal. La paciente aparentemente no sufre de trastornos mentales, y posee un nivel socioeconómico bajo. El presente trabajo constituye el primer reporte documentado de una pseudomiasis entérica por E. tenax en la zona semiárida del estado Falcón, en la región nor-occidental de Venezuela.

Pseudomyiasis is the term used for the accidental entrapment of swallowed fly maggots and/or eggs immediately passing through the digestive tract. We report a case of intestinal pseudomyasis caused by the larvae of the cosmopolitan drone fly Eristalis tenax (Diptera: Syrphidae) in a 39 year old woman, resident in a suburban sector from Coro city, Falcon state, Venezuela. The patient immediately noticed a living larva in her stool. Although patient referred eventually became colic, her physical examination was normal, with no mental disturbance. She was in a low socioeconomic level. This is the first report of an enteric pseudomyasis by E. tenax in the semiarid zone of Falcon state, in the northwestern region of Venezuela.

Epidemiological study of myiases in the Hospital do Andaraí, Rio de Janeiro, including reference to an exotic etiological agent

Myiases are infestations with dipteran larvae in both necrosed and living tissues, the food source of these insects. These illnesses occur in warm humid climates, and are most frequent in developing countries. We assessed the epidemiological aspects and the influence of climate on the occurrence of myiases and the bioagents in patients admitted to the federal Hospital do Andaraí in Rio de Janeiro from February 2007 to 2008. The influence of abiotic factors (temperature, humidity, and rainfall) on the incidence of myiases was investigated by using the Pearson's correlation test. Of the 40 patients studied, the prevalence of myiases was higher in adults, particularly in the 40 to 65 year-old (37.5 percent) African descent males (57.5 percent). Most of the injuries were caused by trauma (62.5 percent). Some patients made use of licit (50 percent) and illicit drugs (17.2 percent). The occurrence of myiases was not affected by the abiotic factors investigated. The cases reported here were treated in only one hospital, indicating that the disease is relatively common. The most frequent bioagent was Cochliomyia hominivorax (Coquerel), but Cochliomyia macellaria (Fabricius), Chrysomya albiceps (Wiedemann) and Dermatobia hominis (Wiedemann) (Diptera: Calliphoridae) were also detected causing myiases. Chrysomya albiceps is an exotic etiologic agent of myiases.

Nasal bots...a fascinating world!

Larvae causing obligatory myiasis are numerous and they may affect cutaneous and subcutaneous tissues, wounds, nasopharyngeal cavities (nasal bots), internal organs and the digestive tract (bots) of domestic and wild animals and humans as well. Nasal bots belong to the Family Oestridae, Subfamily Oestrinae, which includes several important genera: Oestrus, Kirkioestrus, and Gedoelstia infecting Artiodactyla (except Cervidae) in Africa and Eurasia, Cephenemyia and Pharyngomyia infecting Cervidae, Rhinoestrus infecting horses, Cephalopina infecting camels, Pharyngobolus infecting African elephants, and Tracheomyia infecting Australian kangaroos. Nasal bots are widespread in Mediterranean and tropical areas and in affected animals they induce sneezing and nasal discharge which may become caked with dust making breathing very difficult. The aforementioned species of larvae are host-specific but sometimes the may be deposited in human eyes inducing a painful opthalmomyiasis of short duration. The first fascinating trait of these parasites is the very efficient morphological and biological adaptations to parasitism they show either as larvae or as adults, in order to facilitate their survival and search for a suitable host. Nasal bots have reached different degrees of complexity in their life cycles. Indeed, while for some species (e.g., Oestrus ovis, Rhinoestrus usbekistanicus) larvae are injected by flies directly into nostrils and develop in the sinuses before being ejected for external pupation, some other species migrate from eyes to blood before returning to nasal cavities either through the ethmoid bone (Gedoelstia hässleri) or via lungs and bronchi (Gedoelstia cristata). Moreover, larvae are very well-adapted to their environment being able to undergo through hypobiosis either inside or outside the host, according to the climatic environmental conditions and seasonality. The second fascinating trait of nasal bots is related to host behavioural and immune responses against the infection. Host behaviour may in fact prevent larviposition and inflammatory/immune reactions limit larval development. The main pathophysiological mechanisms involve mast cells and eosinophils which destroy the larvae in sensitized animals. The intense eosinophilic reaction has side effects both locally (i.e. on the nasal mucosa) and also generally, with possible interactions with gastrointestinal strongyles (e.g., both worm burdens and fecundity decreased in lambs infected by O. ovis). Infected animals (e.g., sheep, goat, camel, and donkey) firstly suffer from fly strike, when adult flies inject first stage larvae on nostrils: sheep may try to avoid fly swarms but eventually Rangifer tarandus can only manage a terror-stricken look! Secondly, hosts will suffer from myiasis with typical nasal discharge and sneezing related to sinusitis. Clinical manifestations may vary: for example O. ovis induces severe clinical signs in sheep whilst produces few effects in goats! These parasites are diffused in many Mediterranean and tropical countries. Unfortunately, it is commonly believed that bacterial infections induced by nasal bots are of greater clinical importance: this view is not substantiated and the control of this condition depends on treatment with macrocyclic lactones, closantel and nitroxynil. Reinfections are common, and controlling nasal bots is not so simple.