High seroprevalence but short-lived immune response to SARS-CoV-2 infection in Paris (preprint)

Background Although the COVID-19 pandemic peaked in March/April 2020 in France, the prevalence of infection is barely known. Herein, we assessed the serological response against the SARS-CoV-2 virus in a large population working in one institution of the Paris conurbation. We set up two high-throughput and sensitive methods to assess SARS CoV-2 Nucleoprotein and Spike protein-specific IgG response along with a pseudo-neutralization assay in sera. We studied 1847 participants who also answered a web-based survey on clinical symptoms. Methods and Results In May-July 2020, 11% (95% CI: 9.7-12.6) of serums were positive for IgG against the SARS-CoV-2 N and S protein and 9.5% (CI:8.2-11.0) were pseudo-neutralizer. The prevalence of immunization was 11.6% (CI:10.2-13.2) considering positivity in at least one assays. In 5% (CI:3.9-7.1) of RT-qPCR positive individuals, no systemic IgGs were detected. Among immune individuals, 21% had been asymptomatic. Anosmia and ageusia occurred in 52% of the IgG-positive individuals and in 3% of the negative ones. In contrast, 30% of the anosmia-ageusia cases were seronegative suggesting that the true prevalence of infection may reach 16.6%. In sera obtained 4-8 weeks after the first sampling anti-N and anti-S IgG titers and pseudo-neutralization activity declined by 31%, 17% and 53%, respectively with half-life of 35, 87 and 28 days, respectively. Conclusions The population studied being not particularly exposed to SARS-CoV-2 infection is representative of active workers in the Paris conurbation, suggesting that the current epidemiological models may underestimate the true prevalence of infection. The short lifespan of the serological systemic responses hinders retrospective assessment of the epidemic extent.

Characteristics and outcome of SARS-CoV-2 infection in cancer patients. (preprint)

Abstract Background: Concerns have emerged about the higher risk of fatal COVID-19 in cancer patients. In this paper, we review the experience of a comprehensive cancer center. Methods: A prospective registry was set up at Institut Curie at the beginning of the COVID-19 pandemic. All cancer patients with suspected or proven COVID-19 were entered and actively followed for 28 days. Results: Among 9,842 patients treated at Institut Curie between mid-March and early May 2020, 141 (1.4%) were diagnosed with COVID-19, based on RT-PCR testing and/or CT-scan. In line with our case-mix, breast cancer (40%) was the most common tumor type, followed by hematological and lung malignancies (both 13%). Patients with active cancer therapy or/and advanced cancer accounted for 88% and 69% of patients, respectively. At diagnosis, 79% of patients had COVID-19 related symptoms, with an extent of lung parenchyma involvement [≤]50% in 90% of patients. Blood count variations and C-reactive protein elevation were the most common laboratory abnormalities. Antibiotics and antiviral agents were administered in 48% and 7% of patients, respectively. At the time of analysis, 26 patients (18%) have died from COVID-19, and 81 (57%) were cured. Independent prognostic factors at the time of COVID-19 diagnosis associated with death or intensive care unit admission were extent of COVID-19 pneumonia and decreased O2 saturation. Conclusions: COVID-19 incidence and presentation in cancer patients appear to be very similar to those in the general population. The outcome of COVID-19 is primarily driven by the initial severity of infection rather than patient or cancer characteristics.

COVID-19 in breast cancer patients: a cohort at the Institut Curie hospitals in the Paris area (preprint)

BackgroundCancer patients have been reported to be at higher risk of COVID-19 complications and deaths. We report the characteristics and outcome of patients diagnosed with COVID-19 during breast cancer treatment at Institut Curie hospitals (ICH, Paris area, France). MethodsAn IRB-approved prospective registry was set up at ICH on March 13th, 2020 for all breast cancer patients with COVID-19 symptoms or radiologic signs. Registered data included patient history, tumor characteristics and treatments, COVID-19 symptoms, radiological features and outcome. Data extraction was done on April 25th, 2020. COVID-19 patients were defined as those with either a positive RNA test or typical, newly appeared lung CT-scan abnormalities. ResultsAmong 15,600 patients actively treated for early or metastatic breast cancer during the last 4 months at ICH, 76 patients with suspected COVID-19 infection were included in the registry and followed. Fifty-nine of these patients were diagnosed with COVID-19 based on viral RNA testing (N=41) or typical radiologic signs: 37/59 (63%) COVID-19 patients were treated for metastatic breast cancer, and 13/59 (22%) of them were taking corticosteroids daily. Common clinical features mostly consisted of fever and/or cough, while ground-glass opacities were the most common radiologic sign at diagnosis. We found no association between prior radiation therapy fields or extent of radiation therapy sequelae and extent of COVID-19 lung lesions. Twenty-eight of these 59 patients (47%) were hospitalized and 6 (10%) were transferred to an intensive care unit. At the time of analysis, 45/59 (76%) patients were recovering or had been cured, 10/59 (17%) were still followed and 4/59 (7%) had died from COVID-19. All 4 patients who died had significant non-cancer comorbidities. In univariate analysis, hypertension and age (>70) were the two factors associated with a higher risk of intensive care unit admission and/or death. ConclusionsThis prospective registry analysis suggests that the COVID-19 mortality rate in breast cancer patients depends more on comorbidities than prior radiation therapy or current anti-cancer treatment. Special attention must be paid to comorbidities when estimating the risk of severe COVID-19 in breast cancer patients.