Do Blood Phenotypes of Feline AB Blood Group System Affect the SARS-CoV-2 Antibody Serostatus in Cats?

Cats are susceptible to coronavirus infections, including infection by human severe acute respiratory syndrome coronavirus (SARS-CoV). In human ABO system blood groups, alloantibodies can play a direct role in resistance to infectious diseases. Individuals with the AB blood type were over-represented in the SARS-CoV-2 infection group. Blood type AB individuals lack both anti-A and anti-B antibodies, and therefore lack the protective effect against SARS-CoV-2 infection given by these antibodies. Starting from this knowledge, this pilot preliminary study evaluated a possible association between feline blood phenotypes A, B, and AB and serostatus for SARS-CoV-2 antibodies in cats. We also investigated selected risk or protective factors associated with seropositivity for this coronavirus. A feline population of 215 cats was analysed for AB group system blood phenotypes and antibodies against the nucleocapsid (N-protein) SARS-CoV-2 antigen using a double antigen ELISA. SARS-CoV-2 seropositive samples were confirmed using a surrogate virus neutralization test (sVNT). Origin (stray colony/shelter/owned cat), breed (DSH/non DSH), gender (male/female), reproductive status (neutered/intact), age class (kitten/young adult/mature adult/senior), retroviruses status (seropositive/seronegative), and blood phenotype (A, B, and AB) were evaluated as protective or risk factors for SARS-CoV-2 seropositivity. Seropositivity for antibodies against the SARS-CoV-2 N-protein was recorded in eight cats, but only four of these tested positive with sVNT. Of these four SARS-CoV-2 seropositive cats, three were blood phenotype A and one was phenotype AB. Young adult age (1-6 years), FeLV seropositivity and blood type AB were significantly associated with SARS-CoV-2 seropositivity according to a univariate analysis, but only blood type AB (p = 0.0344, OR = 15.4, 95%CI: 1.22-194.39) and FeLV seropositivity (p = 0.0444, OR = 13.2, 95%CI: 1.06-163.63) were significant associated risk factors according to a logistic regression. Blood phenotype AB might be associated with seropositivity for SARS-CoV-2 antibodies. This could be due, as in people, to the protective effect of naturally occurring alloantibodies to blood type antigens which are lacking in type AB cats. The results of this pilot study should be considered very preliminary, and we suggest the need for further research to assess this potential relationship.

Has the Spread of African Swine Fever in the European Union Been Impacted by COVID-19 Pandemic?

African Swine Fever (ASF) is a contagious viral disease of domestic and wild pigs, listed as notifiable by the World Organization for Animal Health (OIE). It causes substantial economic losses to pig farming in the affected countries, with consequent enormous damage to livestock production due to mortality of the animals, and to the restrictions on national and international trade in pigs and derivative products that the presence of the infection implies. To prevent or reduce the risk of ASF introduction, the World Trade Organization (WTO) and the OIE recommend preventive and control measures, such as the ban of live swine and their products traded from ASF-affected to ASF-free countries or zones. The current spread of ASF into Europe poses a serious risk to the industrialized and small-scale pig sector, as demonstrated by observed cases in different EU areas. In this paper the authors discuss the impact of the COVID-19 pandemic on ASF, and the indirect effects including the impact on animal health and disease management. They suggest that the COVID-19 pandemic has severely affected animal disease surveillance control. ASF requires rapid responses and continuous monitoring to identify outbreaks and prevent their spread, and both aspects may have been greatly reduced during the COVID-19 pandemic.