Sepsis is one of the UK’s deadliest health threats, claiming some 48,000 lives annually – that’s more than breast, bowel and prostate cancer combined.
Yet despite decades of research and billions in funding, effective and targeted therapies remain elusive. Why? Because sepsis research is still dominated by cruel experiments on animals that fail to deliver results for human patients.
Mice and rats – whose biology differs significantly from ours – remain the primary subjects used in sepsis experiments. It’s a cruel and ineffective approach that sees promising sepsis treatments fail time and time again.
Heartbreaking
It’s now more than 10 years since renowned intensive care expert Dr Mitchell Fink warned that “most animal models of human sepsis are flawed”.
More than 20 peer-reviewed studies – including one groundbreaking 2013 study with authors from Stanford and Harvard – agree that mice are poor models for human sepsis.
Not only do rodents share little genetic similarity to humans in response to sepsis, burns, and trauma, but the conditions under which they’re deliberately infected to induce sepsis vary far too much to procure reliable outcomes.
This is compounded by the fundamental differences between animal and human experiences of sepsis. The result is a trail of tortured, dead animals, a continuing threat to human life, and a gigantic bill, footed by public funds.
Referring to the 150 drugs that had successfully treated sepsis in mice but failed in human clinical trials, former US National Institutes of Health (NIH) Director, Dr Francis Collins, lamented “a heartbreaking loss of decades of research and billions of dollars.”
Prolonged
So why are mice still the go-to for sepsis studies? Sadly, it’s because they’re cheap and convenient.
In 2023, nearly two million mice were exploited in British laboratories, with many of those used in sepsis research subjected to one of two common testing methods – both of which are excruciating.
One method, caecal ligation and puncture, sees experimenters cut open the animals’ abdomens and puncture their intestines to cause faecal matter and bacteria to leak out.
Animals may experience fever, chills, diarrhoea, difficulty breathing, lethargy, disorientation, septic shock and organ failure.
The other method – endotoxin models, where mice are injected with bacterial toxins – is also heavily criticised due to a lack of human relevance.
Mice require massive toxin doses to trigger a response, resulting in a fast, acute inflammation, unlike the slower, prolonged immune response seen in human sepsis patients.
Tormented
As with much of animal experimentation, after suffering immense pain, the sensitive and curious animals used in sepsis trials are killed.
It’s time for researchers to admit that cruel animal-led research fails to provide useful, human-relevant data to develop effective, and desperately needed, therapies.
The University of Kent has pledged not to conduct any sepsis experiments on animals after hearing from PETA, and now, others must follow.
You can help by urging the Home Office to embrace superior humane methods, like organs-on-chips and other in vitro methods, alongside artificial intelligence and machine learning for early diagnosis and prediction.
We must stop throwing good money after bad. As sepsis survivor Chrissy Matthies put it: “Human patients battling this life-threatening condition – and the animals who are tormented in worthless and wasteful experiments – deserve no less.”
This Author
Dr Julia Baines is head of science policy at People for the Ethical Treatment of Animals, PETA.