Clinical pictures in dogs naturally infected with Angiostrongylus vasorum

In 2015-2018 a study was carried out in various regions of Italy to describe the variability of clinical signs associated with Angiostrongylus vasorum in naturally infected dogs. Faecal samples collected from 1050 dogs in nine Italian regions (northern Italy: Veneto, Friuli Venezia Giulia; central Italy: Abruzzo, Marche, Lazio and Sardinia island; southern Italy: Molise, Campania, Puglia) were subjected to the Baermann technique. During clinical examination, epidemiological data of dogs were registered and the prevalence differences in relation to epidemiological data were tested by Chi-square test or Fisher's exact test using the software SPSS Statistics (version 24.0), with a significant level of p<0.01. Angiostrongylus vasorum was detected in 84 (8.0%) dogs from Campania (64 dogs), Abruzzo (9 dogs), Lazio (7 dogs) and Molise (4 dogs). Prevalence rates detected in dogs ageing >36 - ≤72, and over 72 months (10.4% and 10.8%), were higher (p<0.01) than in dogs ≤36 months old (4.2%). Significantly higher values of prevalence were detected in crossbred (10.9%) than in purebred dogs (3.7%), and almost all (97.6%) positive animals were privately owned. The prevalence rates of A. vasorum were significantly higher in dogs with respiratory signs (23/130, 17.7% vs 61/920, 6.6%), and in those with weight loss (9/33, 27.3% vs 75/1017, 7.4%). Specifically, clinical signs were diarrhea (53.6%), respiratory signs (27.4%), with cough (20.2%) and dyspnea (11.9%) being the most frequent, weight loss (10.7%), haematochezia (6.0%), lethargy (4.8%), exercise intolerance (3.6%), shock (3.6%), neurological signs (2.4%), cyanosis of visible mucosae (2.4%) and coagulopathies (1.2%). Among A. vasorum-positive animals, the high occurrence of diarrhea was significantly related to coinfections with intestinal parasites. The present data confirm that angiostrongylosis should be included in the differential diagnosis of any disorder of dogs that can be clinically compatible, even in the presence of non-respiratory signs, that sometimes can be the only findings in infected dogs. Some risk factors can have a role in the epidemiology of angiostrongylosis but it should be kept in mind that A. vasorum may infect any dog regardless, age, sex, habitat, breed and lifestyle.