The life-threatening condition is caused by an overwhelming immune reaction to infection that damages tissues and organs.
Each year sepsis costs the NHS more than £2 billion and kills around 37,000 patients - more than breast and bowel cancer combined.
Rapid diagnosis and treatment with antibiotics is essential, but it can take up to two days to analyse samples in a laboratory.
In the summer tax manager Craig Stobo launched a charity to raise awareness of the condition, which killed his wife and unborn child.
GP Fiona Agnew was 35 weeks pregnant when she developed symptoms and her daughter Isla was stillborn. Doctors could not save the 38-year-old mother and she died at Forth Valley Hospital in Larbert, Falkirk a few hours later.
Now scientists have discovered a biomarker in the blood that can identify sepsis at the bedside within two hours.
Certain microRNAs, short strands of the genetic molecule RNA, are more likely to be found in the blood of patients with sepsis. They are known to influence disease processes.
Professor Graham Lord, director of the National Institute for Health Research (NIHR) Biomedical Research Centre in London, said: "Sepsis is a hidden killer, causing nearly a third of all hospital deaths. Rapid antibiotic treatment for the condition is vital."