COVID-19 is a novel, rapidly changing pandemic: consequently, evidence-based recommendations in solid organ transplantation (SOT) remain challenging and unclear. To understand the impact on transplant activity across the United States, and center-level variation in testing, clinical practice, and policies, we conducted a national survey between March 24, 2020 and March 31, 2020 and linked responses to the COVID-19 incidence map. Response rate was a very high 79.3%, reflecting a strong national priority to better understand COVID-19. Complete suspension of live donor kidney transplantation was reported by 71.8% and live donor liver by 67.7%. While complete suspension of deceased donor transplantation was less frequent, some restrictions to deceased donor kidney transplantation were reported by 84.0% and deceased donor liver by 73.3%; more stringent restrictions were associated with higher regional incidence of COVID-19. Shortage of COVID-19 tests was reported by 42.5%. Respondents reported a total of 148 COVID-19 recipients from 10 years posttransplant: 69.6% were kidney recipients, and 25.0% were critically ill. Hydroxychloroquine (HCQ) was used by 78.1% of respondents; azithromycin by 46.9%; tocilizumab by 31.3%, and remdesivir by 25.0%. There is wide heterogeneity in center-level response across the United States; ongoing national data collection, expert discussion, and clinical studies are critical to informing evidence-based practices.

Vaccine-induced SARS-CoV-2 antibody responses are attenuated in solid organ transplant recipients (SOTRs) and breakthrough infections are more common. Additional SARS-CoV-2 vaccine doses increase anti-spike IgG in some SOTRs, but it is uncertain whether neutralization of variants of concern (VOCs) is enhanced. We tested 47 SOTRs for clinical and research anti-spike IgG, pseudoneutralization (ACE2 blocking), and live-virus neutralization (nAb) against VOCs before and after a third SARS-CoV-2 vaccine dose (70% mRNA, 30% Ad26.COV2.S) with comparison to 15 healthy controls after two mRNA vaccine doses. We used correlation analysis to compare anti-spike IgG assays and focused on thresholds associated with neutralization. A third SARS-CoV-2 vaccine dose increased median total anti-spike (1.6-fold), pseudoneutralization against VOCs (2.5-fold vs. Delta), and neutralizing antibodies (1.4-fold against Delta). However, neutralization activity was significantly lower than healthy controls (p < .001); 32% of SOTRs had zero detectable nAb against Delta after third vaccination compared to 100% for controls. Correlation with nAb was seen at anti-spike IgG >4 Log₁₀(AU/ml) on the Euroimmun ELISA and >4 Log₁₀(AU/ml) on the MSD research assay. These findings highlight benefits of a third vaccine dose for some SOTRs and the need for alternative strategies to improve protection in a significant subset of this population.

Infections remain a major threat to successful kidney transplantation (KT). To characterize the landscape and impact of post‐KT infections in the modern era, we used United States Renal Data System data linked to Scientific Registry of Transplant Recipients to study 141,661 Medicare‐primary KT recipients from 1/1/1999‐12/31/2014. Infection diagnoses were ascertained by ICD‐9 codes. The cumulative incidence of a post‐KT infection was 36.9% at 3 months, 53.7% at 1 year, and 78.0% at 5 years. The most common infections were UTI (46.8%) and pneumonia (28.2%). 5‐year mortality for KT recipients who developed an infection was 24.9% vs. 7.9% for those who did not, and 5‐year death‐censored graft failure (DCGF) was 20.6% vs. 10.1% (p<0.001). This translated to a 2.22‐fold higher mortality risk (adjusted hazard ratio [aHR]: _2.152.22_2.29, p<0.001) and 1.92‐fold higher DCGF risk (aHR: _1.841.91_1.98, p<0.001) for KT recipients who developed an infection, although the magnitude of this higher risk varied across infection types (for example, 3.11‐fold higher mortality risk for sepsis versus 1.62‐fold for a UTI). Post‐KT infections are common and substantially impact mortality and DCGF, even in the modern era. KT recipients at high risk for infections might benefit from enhanced surveillance or follow‐up to mitigate these risks.

This study of SARS-CoV-2 mRNA vaccination in 14 persons with HIV (PWH) demonstrated uniformly high anti-SARS-CoV-2 receptor binding domain (RBD) antibody titres after two doses, despite varied titres after a single dose. The majority of vaccine reactions were mild and no adverse events occurred.