SARS-Cov-2 Seroprevalence in a French Kidney Transplant Center Located Within a "High Risk" Zone.

BACKGROUND: Data on SARS-CoV-2 seroprevalence in kidney transplant recipients (KTR) remain rare. We sought to shed further light on this issue by conducting a single-center study in a kidney transplant center located in one of the France's highest risk zone (Grand Est) for Covid-19 during the initial disease outbreak.

METHOD: To this aim, we used a survey approach coupled with systematic investigation of SARS-CoV-2 serology in a cohort of 1390 KTR.

RESULTS: SARS-CoV-2 serologies were available for 780 survey respondents, among whom 48 had anti-SARS-CoV-2 antibodies (total seroprevalence: 6.2%). Thirty-five of the 48 seropositive KTR had previously received a diagnosis of Covid-19, whereas the remaining 13 patients were not known to be infected (8 asymptomatic cases). Specifically, 18.7% of seropositive KTR and 1.1% of the entire cohort were asymptomatic. Household exposure was found to markedly increase the risk of SARS-CoV-2 transmission.

CONCLUSION: Our findings demonstrate that the overall SARS-CoV-2 seroprevalence in KTR living in one of the France's highest risk zone for Covid-19 during the first French lockdown was as low as 6.3%. A rapid and strict implementation of protective measures could have significantly mitigated virus spread even in an area of high virus circulation.