The 2026 Conference on Retroviruses and Opportunistic Infections (CROI) furthered our understanding of acute COVID-19, long COVID, postacute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), viral immunity, and SARS-CoV-2 therapeutics. Results of a first-in-human validation study of DNA-encoded monoclonal antibody (DMAb) technology demonstrated safety and robust and durable monoclonal antibody (mAb) production, giving the green light to further develop the DMAb platform. Pemivibart administration to people with advanced HIV was well tolerated and associated with good levels of neutralizing antibodies. A new pan-coronavirus 3C-like protease inhibitor was shown to have similar pharmacokinetics and a similar safety profile in people with renal impairment and people with hepatic impairment. A study of SARS-CoV-2 infections in 2023 demonstrated continued risk for new incident diagnoses and worsening of prior comorbidities in the year after infection. SARS-CoV-2 infection in people with HIV is associated with discernible decline in estimated glomerular filtration rate in the 2 years after infection. A blinded study of circulating SARS-CoV-2 antigen found no association between the presence of antigen and the likelihood of having long COVID. Most people with long COVID in a cohort study have experienced stigma or feeling dismissed in interactions with their clinicians.