Covid-associated sepsis was more common, deadlier than thought: Study

SARS-CoV-2, the virus responsible for Covid-19 was a more common and deadly cause of sepsis during the initial period of the pandemic than previously assumed, according to a study.

The study, led by investigators from Brigham and Women's Hospital, based on electronic health record (EHR) data showed that SARS-CoV-2 accounted for approximately one in six cases of sepsis during the first two and a half years of the Covid-19 pandemic.The results, published in JAMA Network Open, suggest clinicians should rethink how they treat sepsis while also providing a framework for future surveillance for viral sepsis.

"Most people, including medical professionals, equate sepsis with bacterial infections," said lead author Claire Shappell, of the Division of Pulmonary and Critical Care Medicine in the Department of Medicine at Brigham and Women's Hospital.

"This is reflected in treatment guidelines and quality measures that require immediate antibiotics for patients with suspected sepsis. However, viral infections, including the SARS-CoV-2 virus that causes Covid-19, can trigger the same dysregulated immune response that leads to organ dysfunction as in bacterial sepsis.

"Previous research on viral sepsis has been limited. To capture a full and more accurate picture of sepsis cases, the team utilised electronic health records from five hospitals during the study period.

"Previous efforts to quantify the burden of SARS-CoV-2-associated sepsis have been limited by inconsistent definitions and under-recognition of viral sepsis," said senior author Chanu Rhee of the Division of Infectious Diseases in the Department of Medicine at Brigham and Women's Hospital.

Using EHR data between March 2020 and November 2022, the team identified 431,017 hospitalisations from 261,595 individuals. During that time, 5.4 per cent of hospitalisations were due to SARS-CoV-2 infections and 28.2 per cent of those hospitalisations had SARS-CoV-2-associated sepsis.

The mortality rate for patients with SARS-CoV-2-associated sepsis was initially high -- 33 per cent over the first three months of the pandemic. 

However, it declined over time and eventually became similar to the mortality rate for presumed bacterial sepsis, a rate of about 14.5 per cent that remained stable throughout the study period.

"Our study draws attention to the high burden and poor outcomes associated with viral sepsis, while demonstrating the utility of using EHR-based algorithms to conduct surveillance for both viral and bacterial sepsis," said Shappell.

"We also hope our findings highlight that sepsis is not a 'one-size-fits-all' entity, but one that requires clinicians to tailor their diagnosis and treatment strategy to each patient's syndrome and probable pathogen."