Canine and feline cutaneous screw-worm myiasis in Malaysia: clinical aspects in 76 cases.

BACKGROUND: Cutaneous screw-worm myiasis in companion animals either due to the New World screw-worm, Cochliomyia hominivorax or the Old World screw-worm, Chrysomya bezziana, has been reported particularly in tropical and subtropical regions of the world. Although treatment of screw-worm myiasis in dogs has been described, few studies have been conducted regarding its clinical and epidemiological aspects in companion animals. OBJECTIVES: To describe clinical and epidemiological aspects of canine and feline screw-worm myiasis. ANIMALS: Naturally infested dogs and cats, presented to five veterinary clinics in four Malaysian states from September 2017 to February 2018. METHODS AND MATERIALS: Cutaneous screw-worm myiasis was diagnosed based on clinical signs and visual examination of burrowing larvae within lesion. Age, breed, gender, anatomical site of infestation and suspected underlying predisposing causes were investigated. RESULTS: A total of 55 dogs and 21 cats were included in the study. Intact male mixed breed dogs (mean age 58 months) and intact male domestic short hair cats (mean age 24 months) with suspected fight-related wounds were most commonly presented with exudative and ulcerative lesions associated with screw-worm myiasis. The most common anatomical sites of infestation in the dogs were the external ear canals, followed by the perineum and medial canthus. For the cats, the most commonly affected areas were paws and tail. Five cats with screw-worm myiasis were concurrently infected with sporotrichosis. CONCLUSION AND CLINICAL RELEVANCE: Aggression between unneutered animals is a likely underlying cause for cutaneous screw-worm myiasis in both cats and dogs. Sporotrichosis was also a potential predisposing cause for screw-worm myiasis in cats.

Case Report: Myiasis due to Cochliomyia hominivorax and Dermatobia hominis: Clinical and Pathological Differences between Two Species in Northern Peru.

Infestations caused by fly larvae (Myiasis) have been observed in patients with risk factors and in tropical zones. The aim of our study was to describe the clinical and epidemiological aspects and the risk factors associated with the occurrence of obligatory myiasis, as well as the therapeutic approach to patients. We identified the cases of myiasis diagnosed in two referral hospitals in northern Peru from January 2012 to December 2015 and included patients in whom larval development and a compatible clinical profile were observed. Epidemiological, clinical, analytical, diagnostic, therapeutic, and follow-up data were collected from clinical files. Nine clinical cases were compatible with a diagnosis of myiasis; of these, two were pediatric patients, one was a middle-aged adult, and six were elderly patients. Four of the nine patients were male. The identified species were Dermatobia hominis and Cochliomyia hominivorax. The therapeutic approach included antiparasitic therapy with ivermectin, antibacterial, and in some cases, anti-inflammatory drugs. Dermatobia hominis and C. hominivorax are the predominant species causing myiasis in northern Peru.

Screw-worm myiasis of prolapsed rectum.

BACKGROUND: Wound myiasis in the Indian subcontinent is most commonly caused by old world screw-worm (Chrysomya bezziana). CASE REPORT AND MANAGEMENT: A 4-year-old malnourished girl presented with full thickness rectal prolapse following acute diarrhea with a large wound and screwworm myiasis of the rectum. Turpentine oil was applied to immobilize the maggots followed by manual extraction. Prolapse was successfully treated by manual reduction followed by strapping of the buttocks. OUTCOME: Child was thriving well and gained 2 kg weight in follow up after two weeks. MESSAGE: Parents should be educated about taking care of prolapsed rectum.

Miasis oral por Cochliomya hominivotax (Diptera : Calliphoridae) en una paciente geriátrica / Oral myasis by Cochliomyia hominivorax (Diptera : Calliphroridae) in a geriatric patient

Se informa de un caso de miasis oral provocada por Cochliomyia hominivorax en una paciente de 75 años de edad. De la lesión se recuperaron aproximadamente 110 larvas de tercer estadio que perforaron el paladar duro y blando con compromiso de las cavidades periodontales maxilares y región sublingual

Miasis cavitaria de localización oral / Oral cavity myiasis

Se presenta un caso de miasis cavitaria de localización oral, eventualidad poco frecuente en nuestro medio, en un paciente joven con parálisis cerebral y retardo mental grave. Se efectúa una revisión del tema y se plantea la necesidad de la cirugía como única opción válida en este tipo de miasis (AU)

Miasis cavitaria de localización oral / Oral cavity myiasis

Se presenta un caso de miasis cavitaria de localización oral, eventualidad poco frecuente en nuestro medio, en un paciente joven con parálisis cerebral y retardo mental grave. Se efectúa una revisión del tema y se plantea la necesidad de la cirugía como única opción válida en este tipo de miasis

Identification of electrophysiologically-active compounds for New World screwworm, Cochliomyia hominivorax, in larval wound fluid.

Acidic and non-acidic fractions from extracts of fluid from sheep wounds infested with larvae of Cochliomyia hominivorax (Coquerel) were analysed by linked gas chromatography and electroantennography in order to detect electrophysiologically-active compounds that could be potential attractants. Responses to twenty-six electrophysiologically-active compounds were observed and, on the basis of electron impact and chemical ionization mass spectrometry and co-chromatography with authentic compounds, twenty-five of these compounds were characterized. The most abundant compounds identified in the larval wound fluid were straight and methyl-branched aliphatic carboxylic acids, ranging from C2- to C5-carbon chain length. Butanoic acid, for example, was found to be present at approximately 0.45 mg/ml. Aliphatic carboxylic acids with longer chain lengths were also observed but in trace amounts. Three aromatic carboxylic acids, benzoic, phenylethanoic and 3-phenylpropanoic acids were also present but only phenylethanoic and 3-phenylpropanoic acids elicited electroantennographic responses. Phenol and indole were by far the most abundant components of the non-acid fraction of the larval wound fluid with all other components, except delta-valerolactam, present at levels of less than 5% that of phenol which was present at a concentration of 0.05 mg/ml. Electroantennographic studies of straight-chain aliphatic carboxylic acids showed that pentanoic acid elicited the strongest response from C. hominivorax. Similar studies showed that 1-octen-3-ol elicited stronger responses than 3-methylphenol, indole, phenol or dimethyldisulphide. 3-Methylindole, which was not found in the wound fluid, also elicited a strong response. The potential behavioural significance of these compounds is discussed in relation to that of known attractants of C. hominivorax and other dipteran pests of mammals.