SARS-CoV-2 emerged from animals and is now easily transmitted between people. Sporadic detection of natural cases in animals alongside successful experimental infections of pets, such as cats, ferrets and dogs, raises questions about the susceptibility of animals under natural conditions of pet ownership. Here, we report a large-scale study to assess SARS-CoV-2 infection in 919 companion animals living in northern Italy, sampled at a time of frequent human infection. No animals tested PCR positive. However, 3.3% of dogs and 5.8% of cats had measurable SARS-CoV-2 neutralizing antibody titers, with dogs from COVID-19 positive households being significantly more likely to test positive than those from COVID-19 negative households. Understanding risk factors associated with this and their potential to infect other species requires urgent investigation.

Vector-borne diseases (VBDs) are prevalently investigated in dogs. Studies on feline VBDs are scant, though feline leishmaniosis (FeL) is increasingly recognised as a disease of cats in endemic areas. Comprehensive investigations on the distribution of VBDs in populations of cats and dogs living in relatively small geographical areas, such as islands, are currently lacking. In this study the prevalence of Leishmania infantum and other VBD pathogens was assessed in cohorts of cats and dogs living in the Aeolian Islands. Autochthonous animals (330 cats and 263 dogs) of different age and sex were sampled. Blood and conjunctival samples were collected from cats and dogs for serological and molecular testing. Eighty-five (25.8%) cats were positive for L. infantum, 13 (3.9%) for Bartonella spp. and 1 (0.3%) for Hepatozoon felis. One-hundred and ten dogs (41.8%) were positive for L. infantum and three (1.1%) for Hepatozoon canis. The incidence of L. infantum infection in cats positive after one season of exposure to sand fly was 14.7%. Leishmania infantum prevalence and year incidence were higher in dogs than in cats (p=0.0001 and p=0.0003, respectively). Thirty-four cats (10.3%) scored positive for ticks (mean intensity rate of infestation, 2.03±1.4), which were identified to the species level as Ixodes ventalloi and Rhipicephalus pusillus. Conversely, Rhipicephalus sanguineus sensu lato (s.l.) was the only species identified in dogs (10.6%). A larger prevalence of infestation by Ctenocephalides felis was recorded in cats (n=91; 27.6%) than in dogs (n=33; 12.5%) (p=0.0001). In addition, one female Nosopsyllus fasciatus (syn. Ceratophyllus fasciatus) and one male Spilopsyllus cuniculi were also identified in flea-infected cats. VBDs are endemic in the Aeolian Islands being L. infantum the most prevalent vector-borne pathogen circulating between cats and dogs. The overall seroprevalence of FeL herein recorded is higher than that assessed, only by IFAT, in populations of cats in Greece and in Spain. Because L. infantum and VBDs are more commonly associated with dogs, the recognition of cats as hosts of different vector-borne pathogens is of paramount importance towards a better management of these diseases in both animals and humans.

SARS-CoV-2 originated in animals and is now easily transmitted between people. Sporadic detection of natural cases in animals alongside successful experimental infections of pets, such as cats, ferrets and dogs, raises questions about the susceptibility of animals under natural conditions of pet ownership. Here we report a large-scale study to assess SARS-CoV-2 infection in 817 companion animals living in northern Italy, sampled at a time of frequent human infection. No animals tested PCR positive. However, 3.4% of dogs and 3.9% of cats had measurable SARS-CoV-2 neutralizing antibody titers, with dogs from COVID-19 positive households being significantly more likely to test positive than those from COVID-19 negative households. Understanding risk factors associated with this and their potential to infect other species requires urgent investigation.One Sentence SummarySARS-CoV-2 antibodies in pets from Italy.

BackgroundThe efficacy of a slow-release insecticidal and repellent collar containing 10% imidacloprid and 4.5% flumethrin (Seresto, Bayer Animal Health) in preventing Leishmania infantum infection was evaluated in a large population of dogs living in a hyper-endemic area of Sicily (Italy).MethodsA total of 219 dogs, negative for L. infantum were enrolled in a multicentre, controlled study. Dogs were divided into two homogeneous groups, defined as G1 (n = 102) and G2 (n = 117). Before the start of the sand fly season, dogs in G1 were treated with the collar while animals in G2 were left untreated, serving as negative controls. Dogs were serially sampled on day D90, D180, D210 and D300 in order to assess Leishmania infection by IFAT, PCR on skin (D210-D300) and bone marrow (D300) and cytology on bone marrow aspirate (D300).ResultsThree dogs (2.9%) in G1 and 41 (40.2%) in G2 became positive for L. infantum in at least one of the diagnostic tests employed in the study. The number of seropositive dogs in G2 increased in the course of the study from 15 (D90) to 41 (D300), with some of them also positive in other diagnostic tests. Eight (19.6%) of the seropositive dogs in G2 showed an increase in antibody titers ranging from 1:160 to 1:1,280. At the last follow-up, some of dogs in G2 displayed overt clinical signs suggestive of leishmaniosis. The mean incidence density rate at the final follow-up was 4.0% for G1 and 60.7% for G2, leading to a mean efficacy of the collar in protecting dogs at both sites of 93.4%.ConclusionsThe slow-release collar tested in this study was shown to be safe and highly effective in preventing L. infantum infection in a large population of dogs. Protection conferred by a single collar (up to eight months) spanned an entire sand fly season in a hyper-endemic area of southern Italy. The regular use of collars, at least during the sand fly season, may represent a reliable and sustainable strategy for the prevention of leishmaniosis in dogs living in or travelling to an endemic area.

This study investigated the efficacy of two collars for the treatment and prevention of flea infestations. Additionally the effect of these collars on the incidence of Leishmania infantum infection as compared with a group of vaccinated dogs was evaluated. A total of 224 young dogs from private animal shelters were enrolled in April/May into four groups: G1, 55 dogs treated with 10% imidacloprid + 4.5% flumethrin collar (Seresto, Bayer Animal Health); G2, 60 dogs treated with 4% deltamethrin collar (Scalibor protector band, MSD Animal Health); G3, 54 dogs vaccinated with CaniLeish (Virbac Animal Health); and G4, 55 dogs left non-treated as controls. Dogs were followed up at days 120 (September), 210 (December), and 360 (April-May). At those time points, clinical assessments, ectoparasite counts and blood, bone marrow and skin samples, to detect the presence of L. infantum, were performed. The efficacy of Seresto in protecting dogs from flea infestation was 100% (P < 0.01) on day 120 and 210, while animals treated with Scalibor showed a prevalence of the infestation ranging from 23.3% to 33.3% on day 120 and 210, respectively. At the end of the study, the incidence of L. infantum infection in collared dogs—based on animals being positive in any of the tests—was 5.5% in Seresto-treated dogs and 20% in Scalibor-treated dogs, resulting in overall efficacy of prevention of 88.3% for Seresto and 61.8% for Scalibor. No statistical difference was detected in L. infantum positive dogs for bone marrow PCR and/or cytology at day 360 between the CaniLeish (15.4%) and non-treated control dogs (10.0%). Both collars proved to be effective (P < 0.01) in preventing L. infantum infection throughout one transmission season, whereas no significant difference was recorded in the frequency of active infections between dogs vaccinated with CaniLeish and control dogs, emphasizing the importance of using repellent/insecticide actives as a priority measure for protection against canine leishmaniosis.