Myocarditis and Subclinical-Like Infection Associated With SARS-CoV-2 in Two Cats Living in the Same Household in France: A Case Report With Literature Review

Abstract

This report provides the first clinical, radiographic, echocardiographic, and biological description of SARS-CoV-2-associated myocarditis with a 6-month follow-up in a 5-year-old obese male domestic shorthair cat (Cat-1) presented for refractory congestive heart failure, with high cardiac troponin-I level (5.24 ng/ml), and a large lingual ulcer. The animal was SARS-CoV-2 positive on serology. The other cat living in the same household (Cat-2) never showed any clinical sign but was also confirmed SARS-CoV-2 positive on serology. Both cats were SARS-CoV-2 PCR negative. Cat-1 had closer contact than Cat-2 with their owner, who had been in close contact with a coworker tested PCR positive for COVID-19 (Alpha (B.1.1.7) variant) 4 weeks before Cat-1's first episode of congestive heart failure. A focused point-of-care echocardiography at presentation revealed for Cat-1 numerous B-lines, pleural effusion, severe left atrial dilation and dysfunction, and hypertrophic cardiomyopathy phenotype associated with focal pulmonary consolidations. Both myocarditis and pneumonia were suspected, leading to the prescription of cardiac medications and antibiotics. One month later, Cat-1 recovered, with normalization of left atrial size and function, and radiographic and echocardiography disappearance of heart failure signs and pulmonary lesions. An extensive literature review of SARS-CoV-2-related cardiac injury in pets in comparison with human pathology is discussed.

SARS-CoV-2 in Domestic UK Cats from Alpha to Omicron: Swab Surveillance and Case Reports

“…It was reported previously that a SARS-CoV-2-infected cat developed severe respiratory distress and thrombocytopaenia during a household infection, but it was concluded that an unrelated, pre-existing cardiomyopathy caused the observed pathology [ 54 ]. Here, RT-qPCR testing demonstrated that Cat 2A, a previously healthy middle-aged cat, was infected with SARS-CoV-2, which could cause, or exacerbate, cardiac pathology in cats [ 30 , 31 , 32 ]. SARS-CoV-2 related myocarditis and pneumonia was described in a cat with hypertrophic cardiomyopathy (HCM) [ 32 ], and sudden cardiac death in humans who appeared to be recovering from COVID-19 has been reported [ 55 ].…”

“…Here, RT-qPCR testing demonstrated that Cat 2A, a previously healthy middle-aged cat, was infected with SARS-CoV-2, which could cause, or exacerbate, cardiac pathology in cats [ 30 , 31 , 32 ]. SARS-CoV-2 related myocarditis and pneumonia was described in a cat with hypertrophic cardiomyopathy (HCM) [ 32 ], and sudden cardiac death in humans who appeared to be recovering from COVID-19 has been reported [ 55 ].…”

“…There have been other reports of respiratory disease in SARS-CoV-2-infected cats, including cases showing upper respiratory signs [ 27 ], pneumonia [ 28 ] and acute dyspnoea [ 29 ]. Additionally, an epidemiological link between the Alpha variant and myocarditis in dogs and cats was suspected [ 30 ] and severe SARS-CoV-2 associated disease with cardiac pathology was described in two cats [ 31 , 32 ]. Clinical infections with respiratory signs have also been reported in lions and tigers [ 33 , 34 , 35 ], and two tigers in two different locations were euthanised because of worsening respiratory signs (summarised in [ 36 ]).…”

Increase in SARS-CoV-2 Seroprevalence in UK Domestic Felids Despite Weak Immunogenicity of Post-Omicron Variants

“…Currently, the majority of reported natural SARS-CoV-2 infections in felids have been either asymptomatic or subclinical [ 23 ], however, severe sequelae including acute respiratory distress [ 24 ] and myocarditis [ 25 , 26 ] have been documented.…”

Rising SARS-CoV-2 Seroprevalence and Patterns of Cross-Variant Antibody Neutralization in UK Domestic Cats

“…Several clinical outcomes of feline SARS-CoV-2 infection have been documented ( 23 ), from asymptomatic infections ( 24 ) to mild respiratory signs ( 25 ). More severe sequelae include myocarditis ( 26, 27 ), which can be severe and lead to death or necessitate euthanasia. Estimating the frequency of asymptomatic infections by RT-qPCR is technically challenging as there is a narrow window of positivity ( 28 ).…”