Yuri was just a boy before his father began to show him how the world really worked, putting him through gruelling tasks that his father had to do growing up, it was tradition in the household and if Yuri had the nerve to disagree, he'd sure suffer the consequences. Before too long, Yuri was getting a hang on real world problems, at such a young age, he was acting like an adult - Dealing with problems that had arisen, working long hours and becoming the breadmaker of the house, replacing his father who soon after became to sick to work himself.
Work became too much of a chore, he'd miss shifts, turn up late and eventually was fired. Explaining to his parents was going to be tough, he prepared himself mentally and bought up the news to them - They weren't pleased. He explained that he wished to pursue a medical career and help others in anyway he could, dealing with gunshot wounds and the like. With a smile, his father would go on to tell him why that couldn't be.
In order to prove his father wrong, he continuted to go after his dream of being within the medical field, being born in Chernarus was perfect when the Civil War came around, wounded left and right - It sounds awful but it put a smile on Yuri's face. He'd assist where he could but with the constant gunfire, he found it difficult to work but grinded through it under military instruction or he'd find himself 6 feet under.
When the infection hit, Yuri didn't know what to do, he'd border up his house and dig into his emergency supplies cupboard, he'd sit silently most nights, eating when he needed to and ensuring he didn't become dehydrated - He was alone.