A new study by researchers from the Ralph Veterinary Referral Centre, Buckinghamshire-UK, the Université de Montpellier-France, the Centre Hospitalo-Universitaire-France and the Université Claude Bernard Lyon-France has found that the SARS-CoV-2 Alpha variant (B.1.1.7) is able to infecting pets such as cats – dogs and causing a variety of heart abnormalities.
The research describes the infection of domestic cats and dogs by the B.1.1.7 variant. Two cats and one dog were positive to SARS-CoV-2 PCR on rectal swab, and two cats and one dog were found to have SARS-CoV-2 antibodies 2–6 weeks after they developed signs of cardiac disease. Many owners of these pets had developed respiratory symptoms 3–6 weeks before their pets became ill and had also tested positive for COVID-19.
Interestingly, all these pets were referred for acute onset of cardiac disease, including severe myocardial disorders of suspected inflammatory origin but without primary respiratory signs.
These study findings demonstrate, for the first time, the ability for pets to be infected by the B.1.1.7 variant and question its possible pathogenicity in these animals.
The study findings were published in the peer reviewed journal: Veterinary Record.
The COVID-19 pandemic secondary to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant, carrying the spike (S) protein amino acid change D614G (referred to as B.1 variant), has encompassed several millions of cases around the world.
This global situation has favoured the appearance of numerous genomic mutations, some of which have generated variants having selective advantages.1 Three notable variants emerged in late autumn 2020 in several countries, which then spread rapidly across the world, including B.1.1.7 (also referred to as 20I/N501Y.V1) first detected in England, B.1.351 (20J/N501Y.V2) first detected in South Africa and the more recently identified “Brazil” variant P.1 (20I/N501Y.V3).2
These three variants carry a constellation of genetic mutations, including those at the level of the S protein receptor-binding domain (RDB), which is essential for binding to the cell host ACE-2 receptor to facilitate virus entry.
The B.1.1.7 variant, also referred to as variant of concern (VOC) 202012/01 or 20I/501Y.V1, is estimated to have emerged in September 2020 in Kent, a county in the south east of England, and rapidly outcompeted pre-existing variants in England as the consequence of an increased transmissibility and infectivity.2
Multiple lines of evidence indicate that its enhanced transmissibility is driven by the N501Y mutation and the amino acid Δ69/70 deletion in RDB.3 Consequently, the incidence of B.1.1.7 increased rapidly during a national lockdown implemented by the Government of the United Kingdom from 5 November to 2 December 2020, despite rigorous restrictions, causing an extraordinary surge of COVID-19 cases particularly affecting the Greater London area.
As of 7 February 2021, VOC 202012/01 comprised roughly 95% of new SARS-CoV-2 infections in the United Kingdom and has now been identified in at least 86 countries.
The most dominant clinical manifestations of COVID-19 are characterised by acute respiratory signs associated with high mortality. However, with rapidly evolving research on COVID-19 in people, cardiovascular manifestations were also found to occur in 20%–30% of hospitalised patients, including signs of myocarditis, which have been reported in multiple case reports and review articles.4
Several cases of SARS-CoV-2 infection have also been reported worldwide in domestic pets (especially cats and dogs) and it has been suggested that these animals became infected by their owners or handlers. Infections of domestic pets mostly resulted in unapparent to mild digestive and respiratory symptoms such as cough, runny nose, sneezing and conjunctivitis.5-8
Intriguingly, despite the uncontrolled surge of COVID-19 cases occurring in the United Kingdom since November 2020, natural infection of any animal by the UK B.1.1.7 variant has not been documented, neither in England nor anywhere else.
However, in this observational study, we report the first cases of domestic cats and dogs infected by the UK variant of SARS-CoV-2, as well as a potential association with cardiovascular disease, which was the initial main health concern and reason for a referral to a cardiology service.
A total of 26 canine and feline patients were diagnosed with suspected myocarditis at The Ralph Veterinary Referral Centre (TRVRC), based on the outskirts of London (UK), between December 2020 and March 2021. Notably, many owners and handlers of these pets with myocarditis had developed COVID-19 respiratory symptoms and tested PCR positive for COVID-19 within 3–6 weeks before their pets became ill.
Given this coincidence, coupled with the intriguing simultaneous presence of suspected myocarditis in these pets and the B1.1.7 COVID-19 outbreak in the United Kingdom, we decided to investigate SARS-CoV-2 infection in these animals.