Virus Testing Abstract The CNPRC has maintained a pedigreed colony of Indian origin rhesus macaques for over 22 years. The SPF Pedigreed Indian origin rhesus colony includes both an SPF level 1 colony negative for Simian Retrovirus (SRV), Simian Immmunodeficiency Virus (SIV) and Simian T Cell Lymphotrophic Virus (STLV) Herpes B virus (B virus) and an SPF level 2 colony free of three additional viruses including include rhesus cytomegalovirus (RhCMV), simian foamy virus (SFV), and rhesus rhadinovirus (RRV). SARS-CoV-2 assays will also be added to the routine screening panel. The four principal goals of this application are: Continue to expand the SPF Level 2 population relative to Level 1. Include SARS- CoV-2 surveillance as part of the SPF panel. Develop improved and expanded screening and confirmatory tests for detection of SPF agents to facilitate maintenance of the SPF colony. This work includes new assays for agents such as tuberculosis, which represents the first SPF agent. Evaluate addition of Mamu-B*17 to the currently tracked MHC alleles, Mamu-A*01, Mamu-A*08, and Mamu- B*01. Continue the collection and storage of microbiome and lymphocyte samples in the unique biorepository of SPF2 to facilitate future research projects investigating the interaction of HIV with the host microbiome and immune system. Project Summary/Abstract Page 93