Yannick Caron

Freshwater biodiversity data portal

Background: Cercarial dermatitis or swimmer's itch is a skin condition in humans due to the larval forms of bird schistosomes of some species of the genus Trichobilharzia. The life cycle of these schistosomes requires freshwater snails (intermediate host) and waterfowl (definitive host). Repeated exposures to cercariae can lead to skin sensitization with the induction of pruritic skin lesions. Methods: We describe, in this study, two outbreaks of human cercarial dermatitis at the Eau d'Heure Lakes, Belgium. In July and August 2012, a total of, respectively, 78 and 10 people reported a sudden skin rash accompanied by pruritus following recreational activities in the Plate Taille Lake. However, no ocellate furcocercariae were detected following light exposure of the snails collected between September 2012 and September 2013 (n = 402). No outbreaks were recorded in 2013 and 2014. In August 2015, about 30 new cases were recorded. Snails were collected (n = 270) in different locations around the lake. PCR was used to identify accurately the intermediate hosts and the parasite species involved. Results: After light exposure, seven Radix spp. (2.6%) shed ocellate furcocercariae. Molecular identification based on the rDNA internal transcribed spacer 2 sequence ascribed the infected snails to R. balthica ( = R. peregra = R. ovata) (6/7) and R. auricularia (1/7). Based on the amplification of the D2 domain of the 28S rDNA, the cercariae were shown to belong to two different haplotypes of Trichobilharzia franki. Conclusions: This is the first record in Belgium of T. franki and associated skin condition.

OBJECTIVES: To describe Angiostrongylus vasorum infection in a series of clinical cases over a 12‐month period, report the use of quantitative PCR on broncho‐alveolar lavage fluid and investigate the ‐possibility of previously undiagnosed angiostrongylosis in a retrospective cohort of coughing and healthy dogs.METHODS: Pulmonary angiostrongylosis was diagnosed based on compatible clinical signs and positive quantitative PCR on broncho‐alveolar lavage fluid and/or positive Baermann examination. Quantitative PCR was also performed retrospectively on broncho‐alveolar lavage fluid from 65 dogs (55 coughing and 10 healthy dogs), examined between 2008 and 2014; results of Baermann examination were also available in 33 dogs.RESULTS: Seven young adult dogs from Southeastern Belgium with respiratory clinical signs were diagnosed with angiostrongylosis between March 2013 and April 2014. Positive broncho‐alveolar lavage fluid quantitative PCR results and positive Baermann examination were obtained in 5/5 and 2/5 dogs, respectively. In the remaining two dogs, only Baermann analysis was performed. Among the retrospective cohorts, only one broncho‐alveolar lavage fluid from a coughing dog was quantitative PCR‐positive whereas all faecal samples were negative.CLINICAL SIGNIFICANCE: Until recently, canine angiostrongylosis was not reported in Belgium. It should now be included in the differential diagnosis of coughing Belgian dogs. Identification of affected dogs may be aided by quantitative PCR on broncho‐alveolar lavage fluid.

Two dogs were presented for chronic cough unresponsive to long‐term treatment. Thoracic radiograph revealed diffuse bronchial pattern. Bronchoscopy revealed moving worms in the airway lumen, further identified as adults of Crenosoma vulpis. Additionally bronchoalveolar lavage fluid analysis and Baermann faecal analysis revealed the presence of larvae with a morphology compatible with C. vulpis first‐stage larvae. In one dog, a first treatment with oral fenbendazole at 50 mg/kg during seven days failed to cure the infection then a single topical application of 10 per cent imidacloprid +2.5 per cent moxidectin at 0.1 ml/kg was given and was effective. The other dog was successfully treated with two administrations of milbemycin oxime at one‐month interval. This lungworm infection might be underdiagnosed and should be excluded before initiating a long‐term corticosteroid therapy. To the author's knowledge, this is the first time C. vulpis infection is reported in dogs in Belgium.

The present study aims to assess the epidemiological role of different lymnaeid snails as intermediate hosts of the liver fluke Fasciola hepatica in Belgium and Luxembourg.

Dung BT, et al. Korean J Parasitol. 2013 Dec;51(6):657-662. http://dx.doi.org/10.3347/kjp.2013.51.6.657

Parafilariosis is a vectorborne parasitic disease caused by the development of the nematode Parafilaria bovicola in the subcutaneous and intermuscular connective tissues of cattle. On February 28, 2012, the so‐called bleeding spots were observed in two heifers and one bull in a cattle herd close to Namur (Belgium). The animals had been treated in December with an injectable ivermectin/closantel solution (Closamectin pour‐on, Norbrook Lab) at the recommended dosage. Samples of serohaemorrhagic exudate and blood, as well as skin biopsies, were collected. Embryonated eggs of P bovicola in the serohaemorrhagic exudate and high levels of creatine phosphokinase were detected. Clinically affected animals were treated with injectable ivermectin (Ivomec, Merial) at 200 μg/kg. Two epidemiological phone surveys were carried out in the south of Belgium (Wallonia) in order to estimate the geographical distribution of this condition since it was first described and published in 2009. A standardised questionnaire was used and the results were analysed. Most outbreaks were recorded in the provinces of Liege and Luxembourg. The initial source of infection is still unknown, but this parasitic infection is clearly spreading from the initial Belgian outbreak site.

Parafilariosis is a vectorborne parasitic disease caused by the development of the nematode Parafilaria bovicola in the subcutaneous and intermuscular connective tissues of cattle. On February 28, 2012, the so‐called bleeding spots were observed in two heifers and one bull in a cattle herd close to Namur (Belgium). The animals had been treated in December with an injectable ivermectin/closantel solution (Closamectin pour‐on, Norbrook Lab) at the recommended dosage. Samples of serohaemorrhagic exudate and blood, as well as skin biopsies, were collected. Embryonated eggs of P bovicola in the serohaemorrhagic exudate and high levels of creatine phosphokinase were detected. Clinically affected animals were treated with injectable ivermectin (Ivomec, Merial) at 200 μg/kg. Two epidemiological phone surveys were carried out in the south of Belgium (Wallonia) in order to estimate the geographical distribution of this condition since it was first described and published in 2009. A standardised questionnaire was used and the results were analysed. Most outbreaks were recorded in the provinces of Liege and Luxembourg. The initial source of infection is still unknown, but this parasitic infection is clearly spreading from the initial Belgian outbreak site.

Nematode worms were retrieved from the left eyes of two dogs presented for unilateral ocular discharge in Belgium. Morphological and molecular identification were performed and the parasites were identified as Thelazia callipaeda. The history suggested that the infection had been acquired in south‐western France and southern Italy where the disease has been observed regularly for the last 6 and 12 years, respectively. In these two regions, the disease is considered endemic and spreading. To the authors’ knowledge, this is the first case report of canine thelaziosis in Belgium.