Novichok victim Charlie Rowley has made a "small but significant" improvement, according to those treating him in Salisbury.
Charlie Rowley is now conscious, but is in a critical but stable condition, Salisbury District Hospital has said.
Lorna Wilkinson, director of nursing at the hospital, said on Tuesday: "We have seen a small but significant improvement in the condition of Charlie Rowley. He is in a critical but stable condition, and is now conscious.
"While this is welcome news, clearly we are not out of the woods yet. Charlie is still very unwell and will continue to require specialist, round-the-clock care here at Salisbury District Hospital."
The pair fell ill at Rowley's home in Amesbury, near Salisbury, on 30 June.
Ms Sturgess collapsed at about 10:15am and was taken to hospital in an ambulance and Mr Rowley was taken to hospital later that day.
Police have launched a murder inquiry following the death of Ms Sturgess at Salisbury District Hospital, after concerns the pair were exposed to novichok through a contaminated item left over from the attack on the Skripals.
Russian double agent Sergei Skripal and his daughter Yulia fell ill after being targeted with the nerve agent in Salisbury on 4 March.
Yulia Skripal was discharged from hospital in April and her father was discharged in May.
Detectives are still investigating the attempted murders of the Skripals and are considering whether the separate incidents may be linked.
The Kremlin said it was sorry to hear of Ms Sturgess's death but called the suggestion that Russia was involved "absurd".
Russia was accused of targeting the Skripals in March but has denied involvement.
It was confirmed on Wednesday by scientists at the UK's chemical laboratory Porton Down that Ms Sturgess and Mr Rowley had been exposed to novichok.
However officials have said there is no evidence the pair visited any of the sites in Salisbury which were decontaminated after the attack on the Skripals.
Six locations visited by the couple have been cordoned off, including Mr Rowley's home on Muggleton Road in Amesbury, a Boots shop and a baptist church.
CCTV footage showed the pair buying alcohol more than 24 hours before they became seriously unwell.
The couple spent the afternoon and evening of 29 June in Salisbury and visited a number of shops.
Dame Sally said it is "particularly important" for families to take care as the summer holidays begin for children.
On Tuesday morning, a white Audi was removed from Swindon, about 40 miles from Salisbury, as part of investigations into the novichok poisonings.
A red Ford Transit van which Mr Rowley had been a passenger in and a bus taken by the pair the night before they became ill have also been taken away for testing.