Early report on the severity of COVID-19 in hematologic patients infected with the SARS-CoV2 omicron variant

Introduction: Patients with hematologic disease are at high risk of morbidity and mortality from COVID-19 due to disease-inherent and therapy-related immunodeficiency. Whether infection with the SARS-CoV2 omicron variant leads to attenuated disease severity in these patients is currently unknown.

Methods: We assessed clinical and laboratory parameters in 61 patients with underlying hematologic conditions with a SARS-CoV2 omicron variant infection confirmed by nucleic acid amplification testing.

Results: Fifty patients reported symptoms of COVID-19, most commonly fatigue (37 patients, 60.66%) and cough (32 patients, 52.46%). 39.34% of patients reported fever. Dyspnea was reported by 10 patients and 7 patients (11.48%) required oxygen therapy. Anosmia and ageusia were relatively rare, occurring in less than 10% of patients. Severity of SARS-CoV2 infection could be assessed in 60 patients. Five cases of critical illness leading to ICU admission occurred during the observation period. Overall mortality was 9.84% in this patient cohort, with heterogeneous causes of death. The majority of omicron-infected hematologic patients experienced mild symptoms or remained asymptomatic.

Discussion: In this study, symptoms of COVID-19 tended to be milder than described for previous SARS-CoV2 variants. However, the extent to which attenuated severity of omicron-variant SARS-CoV2 infection is caused by altered viral pathogenicity or pre-existing host immunity cannot be inferred from our data and should be investigated in larger prospective studies.