Seroprevalence, biogeographic distribution and risk factors for Aelurostrongylus abstrusus infections in Swiss cats

• Published in: Veterinary parasitology 2019-02, Vol.266, p.27-33
• Main Authors: Gueldner, Emily Katharina, Gilli, Urs, Strube, Christina, Schnyder, Manuela
• Format: Article
• Language: English
• Subjects: Aelurostrongylus abstrusus; Altitude; Animals; Antibodies, Helminth - blood; Antibody detection; Cat; Cat Diseases - epidemiology; Cat Diseases - parasitology; Cats; Enzyme-Linked Immunosorbent Assay; Feces - parasitology; Female; Geography; Male; Metastrongyloidea - immunology; Prevalence; Risk Factors; Seroepidemiologic Studies; Strongylida Infections - epidemiology; Strongylida Infections - veterinary; Switzerland; Switzerland - epidemiology; Temperature
• ISSN: 0304-4017; 1873-2550
• DOI: 10.1016/j.vetpar.2018.12.013

[Display omitted] •We evaluated sera of 4067 cats for antibodies against the lungworm Aelurostrongylus abstrusus.•The prevalence was 10.7% (95% CI: 9.7–11.7%), with differences among bioregions.•Altitude and temperature are limiting factors for A. abstrusus occurrence.•Prevalence is higher in intact cats and in cats aged 11–22 months.•Serology improves our knowledge by overcoming the challenges of faecal tests. The metastrongyloid nematode Aelurostrongylus abstrusus is a worldwide occurring feline lungworm. The spectrum of clinical signs in infected cats ranges from mild (e.g. nasal discharge or cough) to severe respiratory distress. The aim of this seroepidemiological study was to define prevalence and risk factors for A. abstrusus infections in Swiss cats, to assess the biogeographic distribution and to investigate the influence of temperature and altitude on the occurrence of this parasite. Sera of 4067 domestic cats were collected from all over Switzerland, tested for the presence of antibodies against A. abstrusus by a novel ELISA and the results correlated with biogeographic aspects. A subsample of 1000 datasets was used for risk factor analyses. Overall, 10.7% (434/4067, 95% confidence intervals [CI]: 9.7–11.7%) of the cats were tested positive, with variations from 0.0% to 20.0% among ten different biogeographic regions. Differences were significant between the Western (13.9%, CI: 11.4–16.7%) and the Eastern (9.2%, CI: 8.0–10.5%) Swiss Plateau, possibly attributable to the suitability of the areas for intermediate hosts. In total 90.3% (392/434) of the seropositive cats originated from regions lower than 700 m above sea level. Correspondingly, 98.9% (429/434) of positive samples were obtained from regions with a mean temperature higher than −2 °C in January, suggesting altitude and temperature being limiting factors for A. abstrusus infections in Switzerland. Concerning individual risk factors, prevalence was higher in intact (15.5%, CI: 9.5–23.4%) than in neutered cats (5.8%, CI: 7.9–10.4%). Young adult cats (aged 11–22 months) were significantly more often seropositive (10/76, 13.2%, CI: 6.5–22.9%) than kittens aged 1–10 months (1/34, 2.9%, CI: 0.1–15.3%) or adult and senior cats > 22 months (58/889, 6.5%, CI: 5–8.4%). Outdoor cats and cats presenting respiratory signs tend to be more often positive than indoor cats (p =  0.077) and animals without respiratory signs (p = 0.086), respectively. We here confirm that the use of a serological test can