Molecular detection and characterization of SARS-CoV-2 in cats and dogs of positive owners during the first COVID-19 wave in Brazil.

Despite previous reports of SARS-CoV-2 infection in dogs and cats worldwide, the type of swab sample used for its detection through RT-qPCR needs to be better compared and described. Accordingly, as part of a multicenter study in Brazil, the aim of the present study was to assess which rectal or oropharyngeal swabs would be more appropriate for detecting SARS-CoV-2 in cats and dogs, through viral load comparison. Pets of owners diagnosed with COVID-19 in the last 7 days were eligible. A total of 148 animals from four of the five Brazilian geographical regions were analyzed, among which 10/48 cats (20.83%) and 11/100 dogs (11.00%) were positive. The results suggested that oropharyngeal swabs should be considered for SARS-CoV-2 detection, particularly in cats, due to the higher cDNA viral load. Also, the genomic results showed similarities between SARS-CoV-2 animal variants and human variants that were circulating at the time of sampling, thus corroborating the existence of zooanthroponotic transmission. In conclusion, the present study highlighted the importance of SARS-CoV-2 monitoring among cats and dogs, as virus modification may indicate the possibility of mutations in animals and spillover back to owners. Thus, positive individuals should always self-isolate from their pets during COVID-19, to prevent trans-species transmission and mutation.

Can sterilization help to prevent roaming in owned dogs and cats?

In many locations, the highest proportion of roaming dogs and cats, might have owners. The prevention of roaming in owned dogs and cats is a key intervention to reduce the number of unsupervised animals in public spaces. Sterilization is an important population management intervention but it is unclear if, apart from its effects on birth rates and animal behavior, it also affects the roaming status of owned dogs and cats. We formulated a directed acyclic graph to represent a causal hypothesis regarding the effect of sex, age and sterilization on roaming behavior in owned dogs and cats. The causal hypothesis was tested using survey data and Bayesian multilevel logistic regressions. The odds of roaming were lower in sterilized dogs and cats but the credible interval (CI) supported the effect of sterilization only for dogs. The odds of roaming were higher in both male dogs and cats and the CI supported the effect of sex. The CI did not support the effect of age on roaming, irrespective of species. If the observed association between sterilization and roaming was causal, then sterilization may contribute to a reduction in roaming. Studies on other populations and the exploration of other potential determinants of roaming are required to better understand the causal relationship between sterilization and roaming.