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

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.

Feline sporotrichosis in Asia

Sporothrix schenckii sensu lato is currently recognized as a species complex with only Sporothrix brasiliensis, Sporothrix schenckii sensu stricto, Sporothrix globosa and Sporothrix pallida identified to cause disease in the cat. Feline sporotrichosis in Asia is mainly reported from Malaysia where a single clonal strain of clinical clade D, Sporothrix schenckii sensu stricto manifesting low susceptibility to major antifungal classes, has been identified as the agent of the disease. Sporothrix globosa has been identified to cause disease from a single cat in Japan while the specific species of agent has not been identified yet for the disease in Thailand. Despite efforts to elucidate and describe the pathogenicity of the agent and the disease it causes, the paucity of data highlights the need for further molecular epidemiological studies to characterize this fungus and the disease it causes in Asia. Its prognosis remains guarded to poor due to issues pertaining to cost, protracted treatment course, zoonotic potential and low susceptibility of some strains to antifungals.

Cutaneous myiasis in cats and dogs: Cases, predisposing conditions and risk factors

Two cases of cutaneous myiasis diagnosed in 2018 in Emilia‐Romagna region (northern Italy) were reported. The first one, described in a domestic cat Felis silvestris catus L. (Carnivora: Felidae) and caused by Calliphora vicina Robineau‐Desvoidy (Diptera: Calliphoridae), was the first one of this type ever reported in Italy in cats. The second one was described in a domestic dog Canis lupus familiaris L. (Carnivora: Canidae) and caused by Lucilia sericata (Meigen) (Diptera: Calliphoridae) and was unusual because it occurred in absence of lesions. An extensive literature search on cutaneous myiasis in these two domestic animal species was performed in order to draw attention to predisposing conditions and risk factors.

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.

First report of furuncular myiasis in a domestic dog caused by Dermatobia hominis (Linnaeus, 1781) in Colombia

This paper reports a case of furuncular myiasis caused by Dermatobia hominis in a domestic dog from Colombia. A male domestic dog, German shepherd breed, of approximately 2 years old was brought for medical consultation. The reason was the presence of one furuncular lesion and discomfort in the patient. Clinical examination revealed a wound over the sacral area similar to an inflammatory papule, with a central punctum exuding a serosanguinous discharge. In the medical examination was applied pressure around the wound, that allowed evidencing a larva inside the tissue. The applied treatment was surgical removal of the larva in the dog. Treatment was complemented with Cephalexin (20 mg / kg, twice a day orally for 7 days), Meloxicam (0.2 mg / kg, once a day orally for 3 days) and cleaning with chlorhexidine, three times a day until removal of points 7 days later. The larva was sent to Parasitology laboratory of the UDES for morphology identification. The larva was identified as Dermatobia hominis.

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.

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.

Myiasis in domestic cats: a global review

Myiasis is an infestation caused by larvae of Diptera in humans and other vertebrates. In domestic cats, Felis silvestris catus L. (Carnivora: Felidae), four dipteran families have been reported as agents of obligatory and facultative myiasis: Oestridae, Calliphoridae, Sarcophagidae and Muscidae. Among agents of obligatory myiasis, the most frequent genus is Cuterebra Clark (Oestridae) and the most frequent species is Cochliomyia hominivorax (Coquerel) (Calliphoridae). Among the agents of facultative myiasis, the most frequent species is Lucilia sericata (Meigen) (Calliphoridae). A survey of myiasis in cats reported in literature shows that the cases are distributed worldwide and linked to the geographical range of the dipteran species. Factors favouring the occurrence of myiasis in cats are prowling in infested areas, poor hygiene conditions due to diseases and/or neglect, and wounds inflicted during territorial or reproductive competition. The aim of the review is to provide an extended survey of literature on myiasis in cats, as general information and possible development of guidelines for veterinarians, entomologists and other researchers interested in the field.