Man, 23, who died with Covid identified as James Kondilios

The family of 23-year-old scientist and power lifter James Kondilios are in mourning as he's revealed as the young Canberra man who died in a Sydney hospital after testing positive for Covid-19.

Mr Kondilios was a healthy athlete with no underlying health conditions and was double vaccinated, according to NSW Health authorities.

He passed away at St Vincent's Hospital on Tuesday and was included in NSW's count of six Covid-related deaths on Thursday.

In 2015 he represented Australia and won a bronze medal at the Power Lifting World Championships in Finland.

A science graduate from the Australian National University (ANU), Mr Kondilios was awarded a national science prize in 2019 for his work on forestry and climate change.

He won the honour for "his work on which genetic variants of Eucalyptus should be planted in preparation for 2030 & 2050 climate conditions", the agricultural department tweeted at the time.

On social media, shocked friends and family have reacted with devastation, saying it is a reminder of how the pandemic can tragically impact young and healthy people.

"The last message you sent to me was 'couldn't ask for a better friend'," fellow ANU alumni and friend Stephen Ma wrote.

• NT forces unvaccinated into snap lockout after record Covid cases

• Concerns raised over 'sudden shift' in Covid testing

• New mutant Covid variant discovered – but should we be concerned?

"Likewise bro, the years I spent with you will always be a great part of my life, you will always be on my mind to delight me, encourage me and guide me.

"I will try to be a better person just like you bro, kind, sweet, nice to everyone and love everyone."

Another friend said it was a heartbreaking reminder that "even the strongest and wisest can be taken from this world before their time".

Mr Kondilios will be farewelled at a funeral service in Sydney on Thursday.

Do you have a story tip? Email: newsroomau@yahoonews.com.

You can also follow us on Facebook, Instagram, TikTok and Twitter and download the Yahoo News app from the App Store or Google Play.