Surveillance of SARS-CoV-2 in Pets of Harris County, Texas, Revealed More Common Pet Infections in Households With Human COVID-19 Cases.

Local health departments can play a critical role in zoonoses surveillance at the human-domestic animal interface, especially when existing public health services and close relationships with community groups can be leveraged. Investigators at Harris County Veterinary Public Health employed a community-based surveillance tool for identifying severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in dogs and cats in June--December 2021. Diagnosis was made using both RT-qPCR testing of oral and nasal swabs and plaque reduction neutralization testing of serum samples. Recruitment for this free companion animal surveillance program occurred through the following two streams: case-based and event-based. The case-based stream recruited companion animals of confirmed human COVID-19 cases through the Harris County Public Health case investigations platform and used the information from epidemiological investigations of the owners to conduct further investigations of their pet(s). The event-based stream recruited companion animals participating in free or low-cost spay/neuter events at Harris County Pets Resource Center (HCPRC). A total of 97 animals were tested, with the case-based and event-based streams accounting for 36 and 61, respectively. A total of 13 animals (13.4%) tested seropositive including one that also had positive RT-qPCR swabs. Of the positives, 11 (84.6%) were associated with a confirmed human case of SARS-CoV-2 living in the same household including one household with four out of the seven animals positive for SARS-CoV-2 neutralizing antibodies. These two surveillance methods employed at the local level emphasize the importance of the One Health approach and provide a model for future zoonoses surveillance systems.