Prolonged fecal shedding of replication-competent virus, lasting immune activation, and intestinal inflammation in a rhesus macaque after experimental SARS-CoV-2 infection.

Infection of an adult rhesus macaque with SARS-CoV-2 led to viral RNAemia in nose, throat, and lungs. The animal also presented extended fecal shedding of viral genomic and subgenomic messenger RNA and replication-competent virus for more than 3 weeks after infection. Positron emission tomography revealed increased intestinal glucose metabolism which was histologically related to inflammation of the ileum.

SARS-CoV-2 in lions, gorillas and zookeepers in the Rotterdam Zoo, the Netherlands, a One Health investigation, November 2021.

In November 2021, seven western lowland gorillas and four Asiatic lions were diagnosed with COVID-19 at Rotterdam Zoo. An outbreak investigation was undertaken to determine the source and extent of the outbreak and to identify possible transmission routes. Interviews were conducted with staff to identify human and animal contacts and cases, compliance with personal protective equipment (PPE) and potential transmission routes.

A low dose of RBD and TLR7/8 agonist displayed on influenza virosome particles protects rhesus macaque against SARS-CoV-2 challenge.

Influenza virosomes serve as antigen delivery vehicles and pre-existing immunity toward influenza improves the immune responses toward antigens. Here, vaccine efficacy was evaluated in non-human primates with a COVID-19 virosome-based vaccine containing a low dose of RBD protein (15 µg) and the adjuvant 3M-052 (1 µg), displayed together on virosomes. Vaccinated animals (n = 6) received two intramuscular administrations at week 0 and 4 and challenged with SARS-CoV-2 at week 8, together with unvaccinated control animals (n = 4).

Poxvirus MVA Expressing SARS-CoV-2 S Protein Induces Robust Immunity and Protects Rhesus Macaques From SARS-CoV-2.

Novel safe, immunogenic, and effective vaccines are needed to control the COVID-19 pandemic, caused by SARS-CoV-2. Here, we describe the safety, robust immunogenicity, and potent efficacy elicited in rhesus macaques by a modified vaccinia virus Ankara (MVA) vector expressing a full-length SARS-CoV-2 spike (S) protein (MVA-S). MVA-S vaccination was well tolerated and induced S and receptor-binding domain (RBD)-binding IgG antibodies and neutralizing antibodies against SARS-CoV-2 and several variants of concern.

The Post-Acute Phase of SARS-CoV-2 Infection in Two Macaque Species Is Associated with Signs of Ongoing Virus Replication and Pathology in Pulmonary and Extrapulmonary Tissues.

The post-acute phase of SARS-CoV-2 infection was investigated in rhesus () and cynomolgus macaques (). During the acute phase of infection, SARS-CoV-2 was shed via the nose and throat, and viral RNA was occasionally detected in feces. This phase coincided with a transient change in systemic immune activation.