Detective Sergeant Nick Bailey, 38, is now stable and conscious after being in intensive care following the attack.
Ex-Russian spy Sergei Skripal and his daughter Yulia are still critically ill after they were found collapsed on a bench in Salisbury.
DS Bailey was one of the first at the scene when the pair were found slumped in The Maltings on Sunday.
The officer was recognised for outstanding police work in December 2016 when he put a Salisbury rapist behind bars for more than 14 years.
He spent two years building a case against Arthur Bonner, who sexually assaulted numerous victims over four decades between the early 1970s and 2014.
His work was praised by the then chief constable Mike Veale for his dedication and outstanding professionalism and for the sensitive way he dealt with the victims and their families.
Acting Chief Constable of Wiltshire Police, Kier Pritchard, said he had been to visit DS Bailey.
He said: “I’ve known Nick for many years, he’s a great character. He’s a huge presence in Wiltshire Police – well-liked, well-loved, a massively dedicated officer.
“He’s clearly receiving high specialist treatment. He’s well, he’s sat up. He’s clearly not the Nick that I know, but he’s in the safe hands of the medical professionals working in Salisbury District Hospital.
“But he’s very anxious, very concerned. He did his best on that night. I’m proud of all our staff who attended this incident at the Maltings on that night. They responded to try to protect people who were ill, with limited information.”
Messages of support have poured in for DS Bailey from the public and police forces across the country.
More from Salisbury spy
Russian spy poisoning: 21 people have been treated
Salisbury spy: How will UK respond if Russia was behind nerve agent attack?
Sergei Skripal: Who, and what, could be behind ‘poison’ attack?
Russian spy poisoning was a ‘professional hit’, experts say
Former spy and daughter in coma after assassination attempt in Salisbury
Home Secretary to make statement on Salisbury spy poisoning
Sarah Bailey, from Waters Road, Salisbury, said DS Bailey was involved in a case with her a few years ago.
She told the Salisbury Journal: “He was fantastic, so helpful and supportive. I really do hope he has a full and speedy recovery.”