Spanish veterinarians develop a vaccine prototype against COVID-19 effective in cats – Diario Veterinario

Although it has been shown that pets can be infected with the SARS-CoV-2 virus, in most cases the disease is asymptomatic or mild. With the aim of anticipating an adverse future epidemiological situation, researchers at the Complutense University of Madrid (UCM) have developed a vaccine prototype that has been effective in preliminary trials. “In our study we showed a high efficacy of the vaccine prototype in limiting replication viral infection of SARS-CoV-2 in cats, which would help control transmission between animals and prevent them from acting as potential sources of infection”, indicates Sandra Barroso, a researcher at the Viral Immunology and Preventive Medicine Service of the UCM. This study experimental, the results of which have been published in Research in Veterinary Science, has been carried out at the Veterinary Health Surveillance Center (VISAVET) of the Faculty of Veterinary Medicine of the UCM, in collaboration with the Microbial Immunology Unit of the Carlos III Health Institute , as part of the project “Study of the potential impact of COVID-19 on pets and lynxes”. In a first trial phase, two animals were vaccinated intramuscularly with the prototype vaccine. Cats were monitored for possible secondary reactions and serum samples were also taken to assess for antibody production. 35 days after vaccination, the animals were transferred to the high biosafety laboratory (level 3) of the center together with two control animals, where they were infected with the SARS-CoV-2 virus to evaluate the response to the disease. To minimize risks to the research staff, the animals were housed in an isolator that filtered the exhaust air. The animals, in addition to having daily veterinary care, had environmental enrichment to maximize their well-being. The duration of the period of infection and evaluation of the response to the disease was 21 days. “Our vaccine prototype has proven to be effective in this regard, since, in the case of one of the vaccinated animals, the infection was completely avoided, while in the other it was limited to the region of the upper respiratory tract and without excretion of infectious virus”, indicate the UCM researchers. Both vaccinated animals had a strong immune response based on neutralizing antibodies that, as happens in humans vaccinated, helped control the infection. “Although currently the COVID-19 disease is not of great relevance in veterinary medicine, the constant appearance of mutations in the virus could lead to the appearance of new variants that do clearly affect animals. Unfortunately, we cannot rule out new scenarios in which the epidemiology of the disease changes. For this reason, it is important to have control and prevention tools for the different susceptible species”, concludes Barroso-Arévalo.