The media is reporting that Sergei Skripal, the Russian ex-spy who was poisoned – alongside his daughter – by the nerve agent, Novichok, is no longer in a critical condition.
Dr Chris Morris, Medical Toxicology Centre, Newcastle University, said:
“It’s definitely good news that Mr Skripal is no longer in a critical condition. It certainly indicates that the rapid response and treatment provided by the emergency care paramedics and clinicians and the continued care teams down in Salisbury have worked. Not only were the signs and symptoms of nerve agent poisoning recognised early so that the correct treatment was given, but also that the right level of care and continued support has been provided. This has seen a positive outcome for Yulia Skripal and also Mr Bailey, but now appears to be having benefits for Mr Skripal. Given the progress of Ms Skripal who despite receiving a potentially fatal dose of nerve agent is now able to talk and provide information indicating very high levels of brain function, there is no reason to think that Mr Skripal won’t have a similar successful recovery with further continued support.
“We know that nerve agents cause a temporary but potentially lengthy effect on the brain and nervous system. What we also know however, is that with time the body clears the nerve agent away and produces new acetylcholinesterase enzyme, the main target of nerve agents. This takes a while and new research suggests something like this may take up to two weeks to restore sufficient levels of enzyme to restore reasonable nerve function. With high dose exposures this may take longer and is possibly why in this case recovery has taken up to now. What we do know from poisoning cases like this which have involved nerve agent type compounds, is that if the correct treatment is given quickly and the right support provided, then recovery is typically very good.”
Prof Alastair Hay, Professor Emeritus of Environmental Toxicology, University of Leeds, said:
“I’m absolutely delighted to hear he is no longer in a critical condition. It is possible he was being kept sedated for some time after the incident to ensure no overactivity in the brain was caused by the nerve agent, and to wait until the nerve agent was cleared from the body – though we don’t know if this is why he was unconscious.
“Nerve agents inhibit the enzyme acetylcholinesterase – this disrupts the messages across nerves and between nerves and muscle. This disruption causes the signs and symptoms of nerve agent poisoning in individuals.
“If the enzyme is totally blocked by circulating nerve agent, you have to wait for new enzyme to be synthesised – this is happening all the time in the body. Eventually the body will restore the enzyme to full capacity, and nerve function will be restored. This is how it’s possible for people to improve day by day.”
Dr Michelle Carlin, Senior lecturer in forensic & analytical chemistry, Northumbria University, said:
How can someone be improving when they’ve been exposed to a nerve agent?
“Nerve agents generally prevent the body’s natural breakdown of a chemical transmitter, called acetylcholine. This compound is released onto muscles during voluntary and involuntary movements, such as breathing. When a nerve agent is administered, the body has an overabundance of the acetylcholine compound, but treatment with atropine blocks the receptors in the body that normally accept acetylcholine. This allows the body time to recover and try to restore normal functioning.
“There is limited knowledge on the long term effects after recovery from a Novichok nerve agent, however neurological damage has been reported in other historic cases. This may include things like slowing of thought processes, a reduction of physical movement and respiratory problems – but we don’t know yet whether those will happen in this case.”
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