The 49-year-old had been fighting a rare and incurable cancer – mantle cell lymphoma – for the past five years.
He had recently undergone stem cell treatment and chemotherapy to beat a recurrence of the disease, but tested positive for Covid-19 early last month.
Mr Slorance’s wife Louise broke the sad news on social media.
She tweeted: “It is with a broken heart that we say @slorance passed away with Covid-19 on Saturday morning.”
First Minister Nicola Sturgeon was among the first to pass on their respects.
She tweeted: “All of us in @scotgov are devastated by this news and send love to @LouiseSlorance and family.
“Andrew was a wonderful person and made a difference in all he did. He was a crucial part of our resilience team and central to our fight against Covid this year. We will miss him hugely.”
His former colleague at the Southern, John Ross Scott, said: “I was heartbroken and saddened to learn of Andrew’s death.
“He was a friend of over 30 years who for the past five years, has not only been fighting an incurable cancer, but writing a blog on his experiences.
“Drew started work with the short-lived Hawick Weekender and then the Rangers News, before working with us at the Southern Reporter then heading to the Scottish Parliament.
“A true friend and fighter for all that was right, he would return to Hawick at the Common Riding, and though he brushed shoulders with most of the top government ministers in his time he always remained humble and grounded.
“We kept in close touch on Facebook and once while I was chair of NHS Orkney I popped up to his department in St Andrews House for a chat.
“Five years ago when he was diagnosed with mantle cell lymphoma he took it all in his stride and was even fundraising for Maggie’s home of Cancer Care in September.
“When Covid-19 struck he was chief communications officer in the Government emergency response unit and would often Facebook me to keep me right with information I was putting on my Coronovirus Facebook Page, and also explaining what three metres meant when I was a bit too close to folk in photos.
“He really was a star in every sense of the word – a genuine guy with the ability to control.
“A month ago he received his long-awaited stem cell treatment alongside chemotherapy at the Queen Elizabeth University Hospital, but then he contracted Covid-19. Still, he wrote on in moving style of his experiences here on Facebook with his last words being ‘Literally I take every day as it comes. And keep hoping for the best.’
“His home town of Hawick has lost a true hero. I, and journalists from his time in the Borders, will never forget him.
Tributes were also paid by other Scottish ministers.
Health Secretary Jeane Freeman posted: “This is so very sad. Andrew was a lovely, kind man who fought so hard to live and many of us were proud to know and will miss him greatly.
“My heartfelt condolences to you, Louise, and all the family.”
Justice Secretary Humza Yousaf tweeted: “I am devastated. Andrew was one of the kindest people I ever came across.
“Despite his health challenges I can’t remember him with anything other than a smile on his face. The whole Scottish Government family will miss him tremendously.”