People who appear to be suffering from life-threatening sepsis must be treated within an hour, a watchdog has said.
The National Institute for Health and Care Excellence (Nice) said those at high risk of severe illness or death must be reviewed by a senior doctor in hospital within an hour and also start on antibiotics.
The move builds on previous guidance from Nice which says sepsis should be treated as an emergency in the same way as heart attacks.
The new draft standard says people with suspected sepsis and showing at least one sign of being at high risk - such as rapid breathing, high heart rate, confusion, rash or ashen appearance - need immediate treatment.
It advises health professionals in any setting, such as GPs, paramedics and A&E staff, to record vital signs like temperature and heart rate, as well as checking for rashes and skin discolouration.
High-risk patients in hospital settings must then receive intravenous fluids, antibiotics and review by a senior doctor within 60 minutes. If it will take more than an hour to get to hospital, antibiotics can be given in GP practices or by ambulance staff.
Health Secretary Jeremy Hunt said: "Every death from sepsis is a tragedy, yet too often the warning signs are missed.
"We need to get far better at spotting sepsis across the NHS and this advice shows how vital it is for clinicians to treat life-threatening symptoms as soon as possible."
Sepsis is a life-threatening condition that occurs when the body's immune system goes into overdrive as it tries to fight an infection. It must be treated quickly with antibiotics.
Early symptoms include fast breathing or a fast heartbeat, high or low temperature, chills and shivering. Sufferers may or may not have a fever.
Severe symptoms can develop soon afterwards and include blood pressure falling low, dizziness, disorientation, slurred speech, mottled skin, nausea and vomiting.
The condition hit the headlines following the death of 12-month-old William Mead in December 2014.
NHS doctors repeatedly failed to spot he had sepsis, while workers on the 111 helpline mishandled a call from his mother Melissa.
Another child, three-year-old Sam Morrish, from Devon, also died from sepsis in December 2010.
He was also the victim of a catalogue of NHS errors.
Call-handlers at NHS Direct failed to categorise Sam's mother's call as urgent, despite indications that his vomit contained blood.
Even when hospital staff finally realised he was critically ill, they waited three hours before administering the antibiotics that could have saved his life.
Mrs Mead said: "I am delighted that all clinical organisations are coming together to improve care for suspected and confirmed sepsis.
"With over 70% of sepsis cases coming from the community, the guideline for GPs and paramedics to deliver potentially lifesaving antibiotics en route to the hospital is key to treating sepsis early.
"The speed in which sepsis takes over the body - 36 hours in William's case - is frightening."
Nice deputy chief executive Professor Gillian Leng said: "We know from recent case reviews that there are inconsistencies in how people's symptoms are assessed in different settings. More can be done to provide rapid treatment."
The 2015 report by the National Confidential Enquiry Into Patient Outcome And Death highlighted that 40% of people admitted to A&E with sepsis did not have a timely review by a senior clinician.
It also reported avoidable delays in administering antibiotics in almost a third (29%) of cases.
A recent study from the York Health Economics Consortium suggests 260,000 people in the UK develop sepsis every year.
This is 110,000 higher than previous estimates.