A cardiac and subcutaneous canine dirofilariosis outbreak in a kennel in central France

Abstract

Canine dirofilarioses are nematode infections caused by two species of the genus Dirofilaria: D. immitis and D. repens. We describe here an outbreak of D. immitis and D. repens infection in military working dogs (MWDs) housed in a kennel in the Indre department (centre of France). Out of a total of 17 dogs, 6 (35.2%) tested positive for D. immitis, D. repens or both parasites. Infested dogs were treated and prophylactic measures were implemented for the entire kennel staff. To our knowledge, this is the first documented description of an outbreak of canine cardiopulmonary dirofilariasis in the center of France, unlike in the south of this country, where D. immitis and D. repens dirofilariasis are enzootic. In France, as mosquito vectors expand their territory and new non-native vectors are introduced, it is likely that the distribution area of these two diseases of domestic and wild carnivores will be wider and underestimated.

Detection of Canine Vector-Borne Filariasis and Their Wolbachia Endosymbionts in French Guiana

“…This is the first molecular report of filaria and Wolbachia infections from dogs in French Guiana. Dogs are the most implicated reservoir for filariasis [9][10][11]15,17,19]. The control of these vector-borne helminths is based on epidemiological information and the use of adequate diagnostic methods [40].…”

“…Genomic DNA was extracted individually from all blood samples. The detail of the extraction protocol is described elsewhere [9]. Briefly, DNAs were obtained after two lysis steps using a powder glass and proteinase K for the mechanical and enzymatic digestion, respectively.…”

“…First, all samples that tested positive for filarial DNA were subjected to PCR amplification and sequencing analysis using the following systems: The standard (Pan-Nematoda) PCR [9] was used to amplify 1194 pb from the small subunit rRNA gene and the filarial specific (Pan-fil COI) PCR [27] targeting 509 pb from the Cytochrome c oxidase subunit I (cox1) gene. The third PCR was developed to amplify 497-570 pb from the 12S rDNA gene of filarial nematodes (Table 1), while all Wolbachia-positive samples were tested using the standard (W16S-Spec) PCR [30] targeting 438 pb fragment from the 16S rDNA.…”

“…Canine filariasis are a group of canine vector-borne helminth (CVBH) caused by several nematodes belonging to the Onchocercidae family. Canids constitute suitable hosts for many filarial parasites of veterinary and human importance, such as the zoonotic Dirofilaria immitis (Leidy 1856), the agent of cardiopulmonary dirofilariasis (also known as heartworm) in dogs and pulmonary dirofilariasis in human [8], D. repens which causes in humans, like in dogs the subcutaneous filariasis [9]. These two species, together with brugian parasites that cause lymphatic filariasis (e.g., Brugia timori, B. malayi and B. pahangi) [10,11], constitute the most thread-like filarial worms causing millions of canine and human cases throughout the world [12][13][14].…”

Oral migration of Dirofilaria repens after creeping dermatitis

“…Dirofilaria (Nochtiella) repens Railliet & Henry, 1911 is a filarial nematode of the family Onchocercidae. Infected mosquitoes can transmit D. repens both to animals (mostly dogs), and accidentally to humans [7,11,18]. In most cases, the parasite is found in subcutaneous nodules or in the ocular conjunctiva, although some lung and tumor-like infections have been reported [3,15,16].…”