Old World Screwworm myiasis: First report of auricular Chrysomya bezziana myiasis in a dog in Singapore.

A German Shepherd dog was presented to a referral practice for screwworm myiasis affecting the ear. The successful management involved killing the larvae with afoxolaner plus milbemycin oxime and using video otoscopy to completely remove dead larvae. To the best of our knowledge, this is the first case report of auricular myiasis by Chrysomya bezziana in a dog in Singapore and the first report of video otoscopic management of myiasis.

MIASIS OCULAR Y BUCAL, A PROPÓSITO DE DOS CASOS / MYASIS EYE AND MOUTH, BY THE WAY OF TWO CASES

La palabra "miasis" proviene del griego, "myia" que significa mosca. La enfermedad corresponde a los daños causados por la invasión de larvas de moscas a tejidos del hombre u otros vertebrados

The term 'Myiasis' originates from the ancient Greek word 'myia', meaning 'fly'. This disease refers to tissue damage caused by the infestation of fly larvae in humans or other vertebrates

A chromosomal-scale reference genome of the New World Screwworm, Cochliomyia hominivorax.

The New World Screwworm, Cochliomyia hominivorax (Calliphoridae), is the most important myiasis-causing species in America. Screwworm myiasis is a zoonosis that can cause severe lesions in livestock, domesticated and wild animals, and occasionally in people. Beyond the sanitary problems associated with this species, these infestations negatively impact economic sectors, such as the cattle industry. Here, we present a chromosome-scale assembly of C. hominivorax's genome, organized in 6 chromosome-length and 515 unplaced scaffolds spanning 534 Mb. There was a clear correspondence between the D. melanogaster linkage groups A-E and the chromosomal-scale scaffolds. Chromosome quotient (CQ) analysis identified a single scaffold from the X chromosome that contains most of the orthologs of genes that are on the D. melanogaster fourth chromosome (linkage group F or dot chromosome). CQ analysis also identified potential X and Y unplaced scaffolds and genes. Y-linkage for selected regions was confirmed by PCR with male and female DNA. Some of the long chromosome-scale scaffolds include Y-linked sequences, suggesting misassembly of these regions. These resources will provide a basis for future studies aiming at understanding the biology and evolution of this devastating obligate parasite.

Number of rainy days in a week influencing screwworm navel myiasis in beef calves and efficacies of injectable and topical antiparasitics.

Rainfall incidence as a risk factor for umbilical myiasis by Cochliomyia hominivorax in newborn beef cattle and the preventive and curative efficacies of injectable and topical products against its larvae were evaluated. The prevalence of navel myiasis did not differ between sex, however, it did differ between seasons of the year, independent of animal sex, with it being higher in the rainy season than in the dry season for both sexes (males 64.6%, females 62.1%). During the rainy season, rains occurred intermittently and the number of rainy days in a week had a direct influence on prevalence, with an increase (≥87%) in the number of calves with navel myiasis caused by C. hominivorax. When it rained intermittently for four, five and six days in a week during the rainy season, calves had ≈12, 24 and 11 times greater chances, respectively, of having navel myiasis compared to a week without rain during the rainy season. The injectable products did not reach preventive efficacies higher than 35%, while all treatments of topic products reached 100% preventive efficacy at 10 days post-treatment. Only the formulations with 30% dichlorfenthion and 0.32% fipronil achieved 100% curative efficacy. The results reinforce the need for intensified inspection and healing of the umbilicus during the rainy season, mainly during rainier weeks. Furthermore, topical formulations may be a better alternative as a preventive treatment than avermectin formulations. However, the curative efficacy of the topical product containing dichlorvos did not demonstrate a relationship with preventive efficacy for newborn calves.

Geographic Population Genetic Structure of the New World Screwworm, Cochliomyia hominivorax (Diptera: Calliphoridae), Using SNPs.

The New World screwworm, Cochliomyia hominivorax (Coquerel 1858) (Diptera: Calliphoridae), is a serious parasite of livestock, humans, and other warm-blooded animals. It has been eradicated from the northern parts of its historical range down to the Panama-Colombian border where a permanent barrier zone is maintained. This eradication was accomplished through using the sterile insect technique (SIT). In 2016 there was an outbreak of C. hominivorax in the Florida Keys. In only six months, this pest was successfully re-eradicated using SIT, but the geographic origin of the invasion has yet to be resolved. It was previously determined that the Florida flies most likely represented a single invasion, and it was recommended that a finer-scale genetic assessment should be completed. Thus, this current proof-of-concept study aimed to develop a population genetic database using single nucleotide polymorphisms (SNPs) to reference outbreaks and potentially identify the origin of the Florida outbreak. This initial database consists of wild-caught samples from 4 geographic locations as well as laboratory colony samples that originated from 7 additional locations using a genotyping by sequencing (GBS) approach. Geographic population structuring was identified for twelve populations that clustered according to geographic location. The Florida outbreak samples appeared similar to samples from the outer Caribbean cluster which included samples from Dominican Republic and Trinidad and Tobago, however, these results will be further clarified with the replacement of laboratory colony samples with future wild-caught samples.

The microbiome of wild and mass-reared new world screwworm, Cochliomyia hominivorax.

Insect population control through continual releases of large numbers of sterile insects, called sterile insect technique (SIT), is only possible if one can mass-rear large quantities of healthy insects. Adaptation of insect stocks to rearing conditions and artificial feeding systems can have a multitude of negative effects such as inbreeding depression, reduced compatibility with wild strains, unintentional selection for traits that lower fitness after release, and an altered microbiome. Changes to insect microbiomes can have many effects on insects ranging from a reduction in sex pheromones or reduced fitness. Thus understanding these systems is important for mass rearing and the performance of the sterile insect control programs. In this study we explored the microbiome of the New World screwworm, Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae) an economically important parasite of warm-blooded animals. Samples from myiases in cows and wild adults were compared to and mass-reared flies used by the SIT program. Significant differences were observed between these treatments, with wild captured flies having a significantly more diverse microbial composition. Bacteria known to stimulate oviposition were found in both wild and mass-reared flies. Two bacteria of veterinary importance were abundant in wild flies, suggesting screwworm is a potential vector of these diseases. Overall, this study provides the screwworm eradication program a platform to continue exploring the effects associated bacteria have on screwworm fitness.

New World screwworm (Cochliomyia hominivorax) myiasis in feral swine of Uruguay: One Health and transboundary disease implications.

BACKGROUND: Feral swine (Sus scrofa) are highly invasive and threaten animal and human health in the Americas. The screwworm (Cochliomyia hominivorax) is listed by the World Organization for Animal Health as a notifiable infestation because myiasis cases affect livestock, wildlife, and humans in endemic areas, and outbreaks can have major socioeconomic consequences in regions where the screwworm has been eradicated. However, a knowledge gap exists on screwworm infestation of feral swine in South America, where the screwworm is endemic. Here, we report screwworm infestation of feral swine harvested in Artigas Department (Uruguay), where the Republic of Uruguay shares borders with Brazil and Argentina. METHODS: Myiasis caused by the larvae of screwworm were identified in feral swine with the support and collaboration of members of a local feral swine hunting club over a 3-year period in the Department of Artigas. Harvested feral swine were examined for the presence of lesions where maggots causing the myiasis could be sampled and processed for taxonomic identification. The sites of myiasis on the body of infested feral swine and geospatial data for each case were recorded. The sex and relative size of each feral swine were also recorded. Temperature and precipitation profiles for the region were obtained from public sources. RESULTS: Myiases caused by screwworms were recorded in 27 of 618 the feral swine harvested. Cases detected in males weighing > 40 kg were associated with wounds that, due to their location, were likely caused by aggressive dominance behavior between adult males. The overall prevalence of screwworm infestation in the harvested feral swine was associated with ambient temperature, but not precipitation. Case numbers peaked in the warmer spring and summer months. CONCLUSIONS: This is the first report on myiasis in feral swine caused by screwworm in South America. In contrast to myiasis in cattle, which can reach deep into host tissues, screwworms in feral swine tended to cause superficial infestation. The presence of feral swine in screwworm endemic areas represents a challenge to screwworm management in those areas. Screwworm populations maintained by feral swine may contribute to human cases in rural areas of Uruguay, which highlights the importance of the One Health approach to the study of this invasive host species-ectoparasite interaction.

Genomic analyses of a livestock pest, the New World screwworm, find potential targets for genetic control programs.

The New World Screwworm fly, Cochliomyia hominivorax, is a major pest of livestock in South America and Caribbean. However, few genomic resources have been available for this species. A genome of 534 Mb was assembled from long read PacBio DNA sequencing of DNA from a highly inbred strain. Analysis of molecular evolution identified 40 genes that are likely under positive selection. Developmental RNA-seq analysis identified specific genes associated with each stage. We identify and analyze the expression of genes that are likely important for host-seeking behavior (chemosensory), development of larvae in open wounds in warm-blooded animals (heat shock protein, immune response) and for building transgenic strains for genetic control programs including gene drive (sex determination, germline). This study will underpin future experiments aimed at understanding the parasitic lifestyle of the screwworm fly and greatly facilitate future development of strains for efficient systems for genetic control of screwworm.

Chrysomya bezziana (Diptera: Calliphoridae) infestation in two Malaysian cats treated with oral lotilaner.

The most common fly species associated with screwworm myiasis in Southeast Asia is Chrysomya bezziana (Ch. bezziana), the Old-World screwworm. Treatment of screwworm myiasis in cats traditionally has comprised subcutaneous injection of ivermectin or oral administration of nitenpyram, combined with aggressive tissue debridement and larval removal under general anaesthesia. Two cats diagnosed with cutaneous myiasis caused by the larvae of Ch. bezziana were treated with lotilaner. In both cats, a single dose of lotilaner at 6-26 mg/kg, killed all larvae within 24 h, negating the need for general anaesthesia. Both cats were simultaneously infested with Lynxacarus radovskyi (L. radovskyi) which also was eradicated with lotilaner. No adverse reactions were observed and both cats recovered without complications.

L'espèce de mouche la plus fréquemment associée à la lucile bouchère en Asie du sud-est est Chrysomya bezziana (Ch. bezziana), espèce du vieux continent. Le traitement chez le chat consiste en une injection sous-cutanée d'ivermectine ou une administration orale de nitenpyram, associé à un débridement tissulaire agressif et retrait des larves sous anesthésie générale. Deux chats avec myase cutanée causée par les larves de Ch. Bezziana ont été traités avec lotilaner. Pour les deux chats, une dose unique de lotilaner à 6-26 mg/kg, a tué toutes les larves en 24h, sans besoin d'anesthésie générale. Les deux chats ont été infestés simultanément par Lynxacarus radovskyi (L. radovskyi) qui a également été éradiqué par le lotilaner. Aucune réaction indésirable n'a été observée chez les deux chats guéris sans complication.

La especie de mosca más común asociada con la miasis de larvas barrenadoras en el sudeste asiático es Chrysomya bezziana (Ch. Bezziana), la larva barrenadora del Viejo Mundo. El tratamiento de la miasis de larva barrenadora en los gatos ha consistido tradicionalmente en inyección subcutánea de ivermectina o administración oral de nitenpiram, combinado con debridamiento agresivo de tejido y eliminación de larvas bajo anestesia general. Dos gatos diagnosticados con miasis cutánea causada por las larvas de Ch. bezziana fueron tratados con lotilaner. En ambos gatos, una dosis única de lotilaner a 6-26 mg/kg, eliminó a todas las larvas en 24 h, evitando la necesidad de anestesia general. Ambos gatos estaban infestados simultáneamente con Lynxacarus radovskyi (L. radovskyi), que también fue erradicada con lotilaner. No se observaron reacciones adversas y ambos gatos se recuperaron sin complicaciones.

A espécie de mosca mais comumente associada à miíase no sudeste da Ásia é a Chrysomya bezziana (Ch. bezziana), a larva de rosca do Velho Mundo. O tratamento da miíase por larva de rosca em gatos tradicionalmente inclui injeção subcutânea de ivermectina ou administração oral de nitempiram, associado com debridamento agressivo do tecido e remoção larval sob anestesia geral. Dois gatos diagnosticados com miíase cutânea causada pelas larvas de Ch. bezziana foram tratados com lotilaner. Nos dois gatos, uma dose única de lotilaner de 6 a 26 mg / kg matou todas as larvas em 24 horas, negando a necessidade de anestesia geral. Ambos os gatos foram infestados simultaneamente com Lynxacarus radovskyi (L. radovskyi), que também foi erradicada com lotilaner. Nenhuma reação adversa foi observada e os dois gatos se recuperaram sem complicações.

First report of myiasis in dogs caused by Cochliomyia hominivorax (Coquerel 1858) in Colombia.

This paper reports for the first time in Colombia, two myasis cases caused by Cochliomyia hominivorax in stray dogs. Clinical examination of both patients revealed fever and a large wound at the palpebral level on the right side, and multiple perforating wounds in the right posterior limb where larvae were found. The treatment applied was the manual removal of larvae in the dogs, and subsequent eye enucleation in one dog due to the total loss of the upper right eyelid and the severe mechanical damage that the cornea received. Treatment was reinforced with repellents applied around the wounds and antibiotics. This finding of Cochliomyia hominivorax in stray dogs in Colombia raises concerns about the potential of dogs serving as a reservoir for human infection in the region.

Otorhinolaryngological myiasis: the problem and its presentations in the weak and forgotten.

INTRODUCTION: Myiasis is common in tropical regions, but now increasing incidence is seen in the west due to international travel. Otorhinolaryngological myiasis is uncommon and is seen in diabetics, alcoholics or patients unable in self-care. OBJECTIVES: To study presentations of otorhinolaryngological myiasis, identify associated risk factors and species of flies causing myiasis. METHODS: Clinical findings and co-morbidities of 67 myiasis cases were noted. Maggots were identified, manually removed, and patients were managed with topical treatment, systemic ivermectin and antibiotics. FINDINGS: Thirty-three nasal myiasis, 13 aural myiasis and 5 patients with oral myiasis were noted. Seven patients with head neck wounds myiasis and nine patients of tracheostome myiasis were recorded. DISCUSSION: Warm humid climate of tropical regions is a major concern along with co-existing conditions like poor sanitation, alcoholism, psychiatric diseases and neuropathies. Hesitancy is seen in attendants and health care professionals to deal with myiasis. CONCLUSION: Awareness about risk factors is important in avoiding myiasis along with prompt treatment which reduces morbidity. Tracheostome myiasis is an under-documented entity rather than a rare presentation. FUNDING: None.

A review on the occurrence of Cochliomyia hominivorax (Diptera: Calliphoridae) in Brazil / Revisão da ocorrência de Cochliomyia hominivorax (Diptera: Calliphoridae) no Brasil

Abstract Cochliomyia hominivorax (Coquerel, 1858), the New World screwworm, causes primary myiasis in wild and domestic animals in tropical and subtropical regions of Brazil. Although this species is considered to occur throughout the country, organized information about its recorded distribution has not been available until now. This article aimed to provide a comprehensive review of the historical and current data published on both immature (myiasis) and adult stages of C. hominivorax in Brazil. A total of 174 articles were found; of these, 141 articles reported myiasis cases in cattle (146 records), humans (68 records), and other mammalian hosts (40 records), and captures of adult flies were reported in 33 articles. C. hominivorax is widespread in Brazil, having been recorded in 208 municipalities in all major biomes of the country.

Resumo Cochliomyia hominivorax (Coquerel, 1858), a mosca-da-bicheira, causa miíase primária em animais silvestres e domésticos em regiões tropicais e subtropicais do Brasil. Embora esta espécie seja considerada de ocorrência em todo o país, informações organizadas sobre sua distribuição com base em registros não estavam disponíveis até o momento. Este artigo teve como objetivo fornecer uma revisão abrangente dos dados históricos e atuais publicados sobre o registro de estágios imaturos (miíase) e adultos de C. hominivorax, no Brasil. De 174 artigos encontrados, 141 relataram casos de miíase em bovinos (146 relatos), humanos (68 relatos) e outros mamíferos hospedeiros (40 relatos) e capturas de adultos de C. hominivorax foram registradas em 33 artigos. C. hominivorax encontra-se amplamente distribuída no Brasil, tendo sido registrada em 208 municípios brasileiros em todos os principais biomas do país.

Efficacy of sarolaner on the treatment of myiasis caused by Cochliomyia hominivorax (Diptera: Calliphoridae) in dogs.

The aim of this study was to evaluate the larval expulsion, larvicidal effect, retention rate of dead larvae and overall efficacy of sarolaner on the treatment of myiasis caused by New World screwworm Cochliomyia hominivorax in naturally infested dogs. Eight Beagle dogs received a single dose of saroalner 40 mg, with dosage ranging from 2.7 mg/kg to 3.7 mg/kg. Evaluations occurred every 15 min in the first hour, every hour for up to 6 h, and after 24 h of treatment. At 24 h post-treatment, total wound cleaning was performed, including removal and counting of remaining live and dead larvae. The animals received antibiotic, analgesic and wound cleaning support until complete wound healing. The average expulsion of the larvae was 50.9 % occurring mainly after 4 h of treatment. The larvicidal effect was 70.6 % at 6 h after treatment and 100 % at 24 h. The mean retention rate of dead larvae of sarolaner was 33.9 %, The overall efficacy was 100 %, thus making sarolaner an excellent treatment option in myiasis caused by C. hominivorax larvae in dogs.

Bovine freeze-dried blood as alternative for feeding of screwworm larvae / Sangre liofilizada bovina como alternativa para la alimentación de larvas del gusano barrenador del ganado

The myiasis caused by Cochliomyia hominivorax (Coquerel) or screwworm is considered one of the most traumatic and relevant to the region due to its economic implications and its importance in public health. The purpose of this study was to compare the reproductive and developmental indexes of screwworm using citrated and freeze-dried bovine blood, spray-dried bovine blood (currently used by Panama-United States Commission for the Eradication and Prevention of Screwworm ñacronym in spanish [Copeg]) and bovine citrated liquid blood. The use of freeze-dried arises through the premise that, due to its process of elaboration constitutes an alternative of better quality for the feeding of the screwworm in function of the integrity of sanguine proteins during its processing. For the comparison of the different diets, the following parameters were used: pH, total pupae weight, pupae size, total pupae volume, emergency percentage, oviposition percentage and hatching percentage. In the case of freeze-dried blood, it showed better mean (standard deviation) indexes of emergence, 83.42 (11.45), and 73.11 (15.97) (p = .01); and hatching, 89.70 (8.88), and 84.08 (8.29), (p = .004) compared to the diet based on spray-dried blood. By virtue of the above, freeze-dried blood proved to be a source of protein with potential to develop insect breeding programs.

La miasis causada por Cochliomyia hominivorax (Coquerel) o gusano barrenador del ganado (GBG) es considerada una de las más traumáticas y relevantes para la región debido a sus implicaciones económicas y su importancia en la salud pública. El propósito de este estudio fue comparar los índices reproductivos y de desarrollo del GBG con sangre bovina liofilizada citratada, sangre bovina secada por pulverización (actualmente utilizada por la Comisión Panamá-Estados Unidos para la Erradicación y Prevención del Gusano Barrenador del Ganado [Copeg]) y sangre líquida bovina citrata. El uso de liofilizado surge bajo la premisa de que, debido a su proceso de elaboración, constituye una alternativa de mejor calidad para la alimentación del GBG en función de la integridad de las proteínas sanguíneas durante su procesamiento. Para la comparación de las diferentes dietas, se utilizaron los siguientes parámetros: pH, peso total de las pupas, tamaño de pupas, volumen total de pupas, porcentaje de emergencia, porcentaje de oviposición y porcentaje de eclosión. En el caso de la sangre liofilizada, mostró mejores promedios (desviación estándar) de índices de emergencia, 83.42 (11.45) y 73.11 (15.97) (p = .01), y eclosión, 89.70 (8.88) y 84.08 (8.29) (p = .004) en comparación con la dieta basada en sangre secada por pulverización. En virtud de lo anterior, la sangre bovina liofilizada demostró ser una fuente de proteína con potencial para desarrollar programas de crianza de insectos.

Human Chrysomya bezziana myiasis: A systematic review.

BACKGROUND: Myiasis due to Old World screw-worm fly, Chrysomya bezziana, is an important obligate zoonotic disease in the OIE-list of diseases and is found throughout much of Africa, the Indian subcontinent, southeast and east Asia. C. bezziana myiasis causes not only morbidity and death to animals and humans, but also economic losses in the livestock industries. Because of the aggressive and destructive nature of this disease in hosts, we initiated this study to provide a comprehensive understanding of human myiasis caused by C. bezziana. METHODS: We searched the databases in English (PubMed, Embase and African Index Medicus) and Chinese (CNKI, Wanfang, and Duxiu), and international government online reports to 6th February, 2019, to identify studies concerning C. bezziana. Another ten human cases in China and Papua New Guinea that our team had recorded were also included. RESULTS: We retrieved 1,048 reports from which 202 studies were ultimately eligible for inclusion in the present descriptive analyses. Since the first human case due to C. bezziana was reported in 1909, we have summarized 291 cases and found that these cases often occurred in patients with poor hygiene, low socio-economic conditions, old age, and underlying diseases including infections, age-related diseases, and noninfectious chronic diseases. But C. bezziana myiasis appears largely neglected as a serious medical or veterinary condition, with human and animal cases only reported in 16 and 24 countries respectively, despite this fly species being recorded in 44 countries worldwide. CONCLUSION: Our findings indicate that cryptic myiasis cases due to the obligate parasite, C. bezziana, are under-recognized. Through this study on C. bezziana etiology, clinical features, diagnosis, treatment, epidemiology, prevention and control, we call for more vigilance and awareness of the disease from governments, health authorities, clinicians, veterinary workers, nursing homes, and also the general public.

Ophthalmomyiasis Caused by Chrysomya bezziana after Periocular Carcinoma.

We treated a homeless man in Iran with a history of squamous cell carcinoma who had ophthalmomyiasis caused by Chrysomya bezziana parasites. This case highlights a much-neglected condition and describes measures to prevent it.

A review on the occurrence of Cochliomyia hominivorax (Diptera: Calliphoridae) in Brazil.

Cochliomyia hominivorax (Coquerel, 1858), the New World screwworm, causes primary myiasis in wild and domestic animals in tropical and subtropical regions of Brazil. Although this species is considered to occur throughout the country, organized information about its recorded distribution has not been available until now. This article aimed to provide a comprehensive review of the historical and current data published on both immature (myiasis) and adult stages of C. hominivorax in Brazil. A total of 174 articles were found; of these, 141 articles reported myiasis cases in cattle (146 records), humans (68 records), and other mammalian hosts (40 records), and captures of adult flies were reported in 33 articles. C. hominivorax is widespread in Brazil, having been recorded in 208 municipalities in all major biomes of the country.

Development of Chrysomya albiceps Wiedemann, 1819 (Diptera: calliphoridae) and Musca domestica Linnaeus, 1758 (Diptera: muscidae) reared together in pig tissues

Chysomya albiceps and Musca domestica are important for forensic entomology, and human and animal health. This study analyzed the effects of the coexistence of C. albiceps and M. domestica reared in four different assays in two pig tissues, brain and intestine: assay 1, interaction between the larvae of the same age; assay 2, interaction between larvae of C. albiceps 24 hours older than larvae of M. domestica; assay 3, interaction between larvae of M. domestica 24 hours older than the larvae of C. albiceps; assay 4, larvae of both species were reared together in flasks with a small supply of food. Weight of larvae, growth time and imago emergence frequency were studied. C. albiceps responded better than M. domestica under most conditions tested. Larvae of C. albiceps responded better in mixed cultures (together with M. domestica) than in pure cultures (larvae of the same species). In contrast, M. domestica responded better when reared in pure cultures. Both species presented shorter growth times when their larvae were reared in intestine tissue with larvae 24 hours younger than the larvae of the concurrent species, compared to their respective growth times in pure cultures. The results confirmed that trophic interactions are relevant to the successful colonization of carrion by C. albiceps. Coexistence of the two species may result in changes in values of their biological components. The results also help to shed light on the biology of the two species in carrion

Using ecological niche models to describe the geographical distribution of the myiasis-causing Cochliomyia hominivorax (Diptera: Calliphoridae) in southern South America.

In southern South America, namely Argentina and Chile, Cochliomyia hominivorax (Coquerel) is the main myiasic agent on humans and domestic animals. The distribution pattern of the species is poorly known and the southern limit of its geographic distribution is unclear. The aims of this study are to elucidate the basic environmental factors associated with occurrence of this myiasic species, evaluation of models constructed on the basis of occurrence data based on adult specimen records to predict geographic occurrence of myiasis, evaluation of unsurveyed sites of high potential of occurrence of the species, and recognition and prioritization of areas that need medical control and specific prophylaxis practices related to this pest. The maximum entropy modeling system (Maxent) was used. Maps of potential distribution of C. hominivorax were produced using two different datasets, models obtained with all localities known for the species (combining medical data and taxonomic data) and only-taxonomic models (excluding medical data). The results obtained include an updated compilation of occurrence of the species in Argentina and Chile. Predictive models obtained in this work indicated that large areas of central-eastern territory of Argentina has the potential for C. hominivorax occurrence, probably reaching the parallel 42° S as is indicated by the complete datasets. Only-taxonomic models fail to predict those myiasic cases occurring in the nearer areas of the Andean chains. The main variables associated with the distribution of C. hominivorax were, alternatively, isothermality or minimum temperature of the coldest month. These results provide a new analytical resource of high potential for the prevention of myiasis and to supports further epidemiological studies.