Search Results (46)

Proximate visual cues play a crucial role for flies (Order: Diptera) in locating suitable foraging and oviposition sites. This study examined the behavioural responses of two sheep myiasis-causing blowfly species in Australia, Lucilia cuprina (Wiedemann) and Chrysomya rufifacies (Macquart), to six different reflectance levels of green and yellow hues. Both species were influenced primarily by reflectance intensity and proximity to the light source. Lucilia cuprina displayed a nonsignificant preference for moderate yellow (p = 0.25), whereas Ch. rufifacies showed a significant attraction to moderate green (p = 0.004) when presented with a two-choice comparison between moderate green and yellow. When exposed to three reflectance levels under each hue, both species responded most strongly to mid-range intensities in green but not yellow, with no significant differences observed among light and dark shades (p > 0.05). Zonal analyses revealed a significant aggregation of individuals near the light source (Zone C; p < 0.05), indicating that spatial orientation cues may be stronger determinants of attraction. Overall, L. cuprina was more responsive to moderate yellow and Ch. rufifacies to moderate green, but both species were predominantly guided by light-related spatial and intensity cues. These findings provide valuable insight into the visual ecology of blowflies and may be useful in optimising colour and reflectance parameters in the design of future commercial fly traps. Full article

Bovines are suitable hosts and can be affected by fly infestations. Flies pose a significant threat to cattle livestock in Latin America (LA), causing substantial economic repercussions to animal production (reduced productivity, veterinary expenses, and decreased animal welfare) and damage to human health. The most important flies affecting cattle in Argentina, Brazil, Colombia, Mexico, and Uruguay are Haematobia irritans, Dermatobia hominis, and Cochliomyia hominivorax. Due to production losses and the consequent economic costs associated with these flies, control measures must be implemented, primarily relying on insecticidal products. However, decision-making for preventing and treating animals with insecticides varies due to differences in environmental conditions across countries and regions, production systems, animal populations, infestation levels, animal welfare, and the prevalence of myiasis, among other factors. Although insecticides remain the most effective option for fly control in cattle, resistant populations have developed, rendering them less effective. To overcome fly resistance to insecticides, non-chemical (mechanical, environmental, biological, and genetic) methods are being integrated into alternative control and eradication strategies. The use of integrated livestock fly control contributes to safeguarding animal, public, and environmental health. This review is designed to support individuals and institutions, both civil and governmental, addressing the ongoing challenge posed by flies affecting livestock. Full article

Background: Parasitic skin-related conditions represent a frequent and evolving challenge in human dermatology, as they often mimic other dermatoses, and are increasingly complicated by therapeutic resistance. With this study, we aimed to provide a practical, clinician-oriented overview of our experience, contextualising it within the current literature. Materials and Methods: We conducted a retrospective, single-centre observational study, reporting a case series of 88 patients diagnosed with parasitic or arthropod-related skin infestations at the San Raffaele Hospital Dermatology Unit (Milan) between 2019 and 2024, and integrated a concise narrative review of contemporary evidence on diagnosis, non-invasive imaging and management. For each case, we documented clinical presentation, dermoscopic or reflectance confocal microscopy (RCM) findings, and treatment response. Non-invasive tools (dermoscopy, videodermoscopy, RCM) were used when appropriate. Results: The spectrum of conditions included flea bites, bed bug bites, cutaneous larva migrans, subcutaneous dirofilariasis, Dermanyssus gallinae dermatitis, pediculosis, tick bites (including Lyme disease), myiasis, scabies, and cutaneous leishmaniasis. One case of eosinophilic dermatosis of haematologic malignancy was also considered due to its possible association with arthropod bites. Non-invasive imaging was critical in confirming suspected infestations, particularly in ambiguous cases or when invasive testing was not feasible. Several cases highlighted suspected therapeutic resistance: a paediatric pediculosis and three adult scabies cases required systemic therapy after standard regimens failed, raising concerns over putative resistance to permethrin and pyrethroids. In dirofilariasis, the persistence of filarial elements visualised by RCM justified the extension of antiparasitic therapy despite prior surgical removal. Conclusions: Our findings underline that accurate diagnosis, early intervention, and tailored treatment remain essential for the effective management of cutaneous infestations. The observed vast spectrum of isolated parasites reflects broader health and ecological dynamics, including zoonotic transmission, international mobility, and changing environmental conditions. At the same time, diagnostic delays, inappropriate treatments, and neglected parasitic diseases continue to pose significant risks. To address these challenges, clinicians should remain alert to atypical presentations, and consider a multidisciplinary approach including the consultation with parasitologists and veterinarians, as well as the incorporation of high-resolution imaging and alternative therapeutic strategies into their routine practice. Full article

Background and Clinical Significance: Furuncular myiasis is a tropical parasitic skin infestation caused by dipterous fly larvae, most commonly affecting travellers to endemic regions. While returning travellers typically present with one or few lesions, extensive parasitism is rare. Increased global mobility and expanding ecological range of myiasis-causing species underscores the need for clinicians in endemic and non-endemic regions to recognise, diagnose, and manage this condition promptly. Awareness of exposure risks—including soil contact, infested clothing, and poor living conditions—is essential to reducing morbidity and preventing complications like secondary bacterial infection. Case Presentation: A healthy male in his forties returned to the UK after a month-long visit to rural Ethiopia, during which he slept on dirt floors and hung his washing on a line. He developed pruritic papular lesions that progressed to erythematous furuncles with central puncta and purulent discharge, accompanied by sensations of movement. The patient self-extracted 12 larvae in Ethiopia and subsequently sought local medical attention, receiving Albendazole, after which emerging larvae were non-motile. On UK presentation, he had 27 lesions at varying stages, 3 with signs of secondary infection. Laboratory investigations revealed elevated inflammatory markers, and wound swabs grew scanty Streptococcus pyogenes. Management included wound occlusion and systemic antibiotics. No further larvae were retrieved, precluding definitive speciation. All lesions improved over subsequent reviews. Conclusions: This case illustrates an unusually extensive presentation of presumed Cordylobia spp. myiasis in a returning traveller, highlighting potential complications following larvicidal therapy. Clinicians should maintain a high index of suspicion for myiasis in patients with compatible cutaneous lesions and relevant history. Increasing travel and shifting vector distributions make familiarity with tropical dermatoses and provision of effective safety measures essential in clinical practice. Full article

Myiasis, derived from the Greek “myia” (fly) and “iasis” (disease), refers to infestation by dipterous larvae. First coined by Hope in 1840 and later defined by Zumpt, myiasis involves larvae feeding on live or necrotic tissues. Oral myiasis, a rare condition first described by Laurence in 1909, typically affects individuals with compromised oral hygiene, necrotic lesions, or systemic debilitation. We report a case of oral myiasis in a 73-year-old non-ambulatory female with multiple comorbidities. The patient presented with pain and swelling in the maxillary anterior region, accompanied by severe halitosis, poor oral hygiene, and live larvae emerging from necrotic oral tissues. Clinical and entomological examination identified the larvae as Chrysomya bezziana. Necrotic tissue was surgically debrided, mobile teeth extracted, and the patient was followed up after anti helminthic medications. Post-operative care included oral hygiene instruction and follow-up. The patient responded well to the treatment. Oral myiasis is an uncommon yet serious condition, predominantly affecting debilitated or geriatric patients with poor oral hygiene. Awareness and early intervention are crucial for effective management. Preventive strategies such as routine oral care and regular follow-up are essential, especially in vulnerable populations. Full article

Background: Human nasal myiasis is a rare zoonotic infection caused by Oestrus ovis with a non-specific clinical presentation that can mimic more common conditions such as allergic rhinitis. Objective: To report a series of nasal myiasis cases in immunocompetent individuals, emphasizing the clinical presentation and complementary investigations (endoscopic findings, parasitological identification, skin prick tests, and imaging studies) that facilitate differential diagnosis from allergic rhinitis and enable early treatment. Methods: We conducted a retrospective study including cases of nasal myasis diagnosed and managed at the ENT department of the Military Hospital of Tunis over an 18-year period (2007–2025). Demographic, clinical, diagnostic, and therapeutic data were analyzed. Results: The mean age was 43 years, with a female predominance. Most patients presented with acute rhinological symptoms initially suggestive of allergic rhinitis. Nasal endoscopy revealed larvae in 79% of cases with parasitological confirmation of Oestrus ovis. Facial CT scans performed in five cases (36%) were unremarkable. Management consisted of multiple daily nasal saline irrigations and albendazole, in association with oral corticosteroids and antihistamines, resulting in symptom resolution within an average of 4 days. Conclusions: Nasal myiasis should be considered in atypical or treatment-resistant rhinitis. Nasal endoscopy is essential for diagnosis. Full article

This study aims to assess the current situation of the main nasal bot flies (Cephenemyia stimulator and Oestrus ovis) affecting roe deer in Spain and to identify the factors influencing their spread. Between 2018 and 2025, 1600 roe deer heads were examined. The overall prevalence of C. stimulator was 39.9% (CI 95% 37.5–42.3), with a mean larval intensity of 44.1 (SD 71.99). In contrast, a low mean larval burden of O. ovis (2.6; SD 1.90) was found in 1.6% of the animals (CI 95% 1.0–2.3). Our findings revealed the first case of mixed myiasis caused by both oestrids. Roe deer abundance was the main risk factor for the prevalence of C. stimulator, whereas larval burden was significantly highest in young animals. In addition, the percentage of infested animals and larval intensity was generally higher in northern areas. The high prevalence of C. stimulator in Spain and its notable increase in recent years indicate that control measures must be taken. Our results reveal that preventing roe deer overpopulation, especially in northern regions of the country, would be key to decreasing the likelihood of nasal bot fly infestation. Full article

Cobboldia elephantis (Oestridae: Gasterophilinae) is an obligate parasite of the alimentary tract of the Asian elephant, causing gastric myiasis. Current knowledge of its first instar larval morphology has been limited to observations under light microscopy, significantly constraining our understanding of morphological evolution within the genus Cobboldia and the broader subfamily Gasterophilinae. In this study, we provided ultrastructural and three-dimensional characterizations of C. elephantis using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) based on newly hatched first instar larvae. Features of the first instar larva of C. elephantis, which are either unique or shared with C. loxodontis Brauer, 1896, include (i) three pairs of mouthhooks, (ii) posterior spiracles bearing peristigmatic tufts, (iii) anal division with two spine-clusters and a row of elongated spines, and (iv) a planed, button-like sensilla and a sensillum placodeum. We also compared the first instar larval morphology of C. elephantis with that of Cobboldia loxodontis, Gyrostigma rhinocerontis (Owen, 1830), Gasterophilus pecorum (Fabricius, 1794), Portschinskia magnifica Pleske, 1926, and Oestrus ovis Linnaeus, 1758. Species of Gasterophilinae share several unique features of the first instar larva, including (i) an anal division composed of three subdivisions, (ii) spiracular slits on the posterior spiracles, and (iii) conserved positioning of thoracic sensilla. These findings fill a key gap in our knowledge of C. elephantis larval morphology and suggest that these distinctive structures play a role in adaptation to its parasitic lifestyle. Full article

Since the first documented case of Cephenemyia stimulator in Spain in 2001, this myiasis has experienced rapid expansion, with the first case also detected in 2021 in Portugal. Between January 2020 and October 2024, a study was carried out in northern Spain (Cantabria, Galicia, País Vasco and Principado de Asturias) and Portugal (Bragança, Viana do Castelo and Vila Real) to evaluate the presence and distribution of this myiasis in these areas. The prevalence of infestation was 76.6 ± 4.72% (95% CI) and 38.78 ± 13.78% (95% CI), with a mean intensity of 62.27 ± 104.40 and 37.74 ± 36.84 larvae per animal in Spain and Portugal, respectively. Regarding age, larval intensity was significantly higher in young animals (109.76 ± 148.59) than in adults (32.22 ± 39.01) and old animals (33.64 ± 34.21) (p < 0.05). These results reflect a large increase in the prevalence and importance of younger animals in the spread of the disease. Therefore, it is very important to control and manage populations, focusing on the youngest animals. Full article

Background: The aging of fly larvae is primarily determined by their temperature-dependent growth rates, a concept widely applied in forensic entomology to estimate the minimum postmortem interval using the accumulated degree day/hour (ADD/ADH) method. Method: This study adapted the same approach for veterinary entomology, offering insights into how accumulated degree day (ADD) can be used to estimate both the number and timing of fly generations in nature. This study details a method for identifying the pupation landmarks of Ch. rufifacies (Macquart) by characterising seven distinct pupal stages over time. Following this, ADD values were calculated for each life stage using developmental data collected from two types of ovine muscle: muscle with fat and muscle without fat, at two temperatures: 24 ± 1 °C for autumn and 30 ± 1 °C for summer, reflecting typical seasonal conditions in southwestern Australia. Results: This study also provided a graphical illustration of how to estimate the number of fly generations emerging during a season, based on daily temperature data from autumn and summer in southwestern Australia for the 2023/2024 period. Conclusions: This approach highlights the value of developmental data and ADD methods in veterinary entomology, offering a robust framework for understanding fly population dynamics for effective myiasis control strategies. Full article

Calliphoridae, or blow flies, are of much ecological and practical importance given their roles in decompositional ecology, medical and veterinary myiasis, and forensic entomology. As ephemeral and rapidly developing species, adults are frequently not present for identification, but puparia (the remaining outer integument of the third instar larvae) are frequently found. These heavily sclerotized remains are stable in the environment but they are of a conservative character. Historically, scanning electron microscopy (SEM) has been used for characterization, a technique which is not only time-consuming but also often expensive, effectively making large numbers of specimens impossible to quantify. As an alternative, confocal laser scanning laser microscopy (CSLM) was tested for utility in providing superior data over SEM. Furthermore, due to the use of intrinsic autofluorescence for imagining, CSLM is significantly more rapid than SEM, requiring no preparation for imaging. Three channels of excitation and emission spectra provided not only image data from the pupal wall but also from the hydrocarbons found upon the puparia. The excitation wavelengths were 404.7, 488, and 640.5 nm, and the emissions were 425–475, 500–550, and 663–738 nm. For ten species of calliphorids, CSLM was used to image puparia. Not only did this provide characters for species identification but it also allowed for the examination of hundreds of specimens. Full article

The infestation of ruminants by fly larvae of the Oestridae family can lead to nasopharyngeal or subcutaneous myiasis, which can harm animal welfare and productivity on sheep and cattle farms. The infestation of wild ruminants allows them to serve as reservoirs for subsequent transfer to domestic animals. The fly species most commonly responsible for myiasis have been well studied in many parts of the world, but less so in southeastern Europe. Here, we identified three botfly species among 197 subcutaneous larvae and 138 nasopharyngeal larvae from 36 wild roe deer (Capreolus capreolus) and 9 wild red deer (Cervus elaphus) at 30 locations across Croatia. Instars were stored in 75% ethanol and their species and developmental stage were identified based on morphological and morphometric keys. Subcutaneous larvae in both cervid species were identified as Hypoderma diana, while nasopharyngeal larvae were identified as Cephenemyia simulator in roe deer and Pharyngomyia picta in red deer. Partial sequencing of the gene-encoding mitochondrial cytochrome oxidase subunit I confirmed the taxonomic classification of C. stimulator and P. picta but was unable to confirm that of H. diana for lack of previously published sequences. This study appears to be the first to combine the morphological and molecular characterization of myiasis-causing botflies in wild cervids in southeastern Europe. Full article

Camel bot fly (Cephalopina titillator) larvae cause myiasis in domesticated and wild camels, resulting in significant economic losses to the camel industry and posing a serious global public health concern. To date, only one mitochondrial genome (mitogenome) of C. titillator isolated from the Alxa Bactrian camel has been reported. Herein, C. titillator was isolated from the Junggar Bactrian camel to assemble a complete circular mitogenome with a length of 16,552 bp encoding 13 protein-coding genes, 22 tRNA genes, and two rRNA genes. The mitogenome showed a high A + T content (73.31%), positive AT-skew (0.12), and negative GC-skew (−0.34) base composition patterns. All protein-coding genes (PCGs) employed ATG, ATA, ATT, GTG, or TCG as the start codons and TAA, TAG, or single T as the stop codons. Similar to other parasites in the Oestridae subfamily, the mitogenome was structurally conserved, with genes retaining the same order and direction as those in the ancestral insect mitogenome. The phylogenetic analysis clustered this species with the Oestrinae, showing that the subfamily did not exhibit monophyly. C. titillator isolated from the Junggar Bactrian camel was found to be a sister lineage to that isolated from the Alxa Bactrian camel. Despite the lack of data on the mitogenome of C. titillator isolated from dromedaries in the Middle East, phylogenetic analysis of C. titillator isolated from Xinjiang revealed one distinct lineage of the Xinjiang camel nasal bot fly. In conclusion, this study reports the complete mitogenome of Xinjiang C. titillator for the first time, providing valuable data for future studies on the phylogenetic relationships in this subfamily. Full article

Background: Human myiasis, the infestation of tissues by dipterous larvae, commonly manifests as painful, raised skin lesions, particularly in tropical regions such as Latin America, where Dermatobia hominis (the human botfly) is a frequent cause. With increased international travel, cases of travel-related myiasis have become more prevalent, necessitating awareness among healthcare providers in non-endemic regions. Methods: We present a case of cutaneous myiasis in a 69-year-old male who returned to the United States from Belize. The patient exhibited a painful skin lesion on his right knee, initially suspected to be an insect bite. The diagnosis was confirmed through ultrasound imaging, which revealed the presence of a subcutaneous larva. Conservative larva removal efforts failed, leading to surgical extraction of the larva. Results: The surgical intervention successfully removed the larva in its entirety, with the wound healing well after the procedure. Pathological examination confirmed the larva as Dermatobia hominis. The patient experienced a satisfactory recovery, with no complications observed during follow-up. Conclusions: This case underscores the importance of considering myiasis in the differential diagnosis of patients presenting with painful skin lesions following travel to tropical regions. As globalization increases, healthcare providers should be vigilant in recognizing and appropriately treating travel-related diseases such as myiasis to ensure prompt and effective care. Full article

The present study investigates the developmental process of Chrysomya rufifacies (Macquart) pupae and their dependency on soil composition, moisture levels, and temperature changes. This research holds implications for forensic and veterinary applications, providing crucial insights for estimating minimum postmortem intervals and managing myiasis-causing flies in diverse environments. Specifically, the study explores the impact of five moisture content levels in loam and sandy soils (0%, 20%, 40%, 60%, and 80%) on the pupal development of Ch. rufifacies under two distinct constant temperature regimes (24 ± 1 °C and 30 ± 1 °C). A significant correlation was observed between soil type and temperature regarding the time required to complete the pupal stages; however, moisture had no significant impact. Larvae exhibited varying survival rates across the two temperatures and five moisture levels in the two types of soils, particularly under extremely lower moisture conditions (0%) at 30 ± 1 °C, failing to progress to the pupariation stage. Additionally, growth parameters such as pupal length and width of the fully formed puparia were significantly impacted by temperature, soil type, and moisture level. Adult head width was systematically measured across different moisture levels and soil types, revealing distinct temperature-dependent responses. Furthermore, a sex-specific analysis highlighted that female Ch. rufifacies consistently displayed larger head widths and higher emergence rates compared to their male counterparts. This research enhances our understanding of the intricate interrelationship among three environmental variables: soil type, moisture level, and temperature, elucidating their collective impact on the pupation processes of dipterans. Full article