Swiatek's victory stretches the 22-year-old's Roland-Garros winning streak to 11, and improves her lifetime record on the Parisian clay to 25-2.
Remarkably, Swiatek has reached the quarter-finals while dropping just nine games and spending 4:04 on the court. The rested and ready Pole will take on last year's runner-up Coco Gauff in quarter-final action next.
Brutal decision for Tsurenko
It was a tough outing for Tsurenko, who saw the trainer after the fifth game against Swiatek, and was forced to retire a game later.
The Ukrainian later told reporters that she started to feel symptoms of her illness before her third-round win over Bianca Andreescu on Saturday. Unable to shake free of her illness, she felt considerably worse on Monday.
"It was tough for me," Tsurenko said. "I could not practise yesterday, and today it was tough for me to warm up - I had to stop because it was not the way I wanted to be on court and to play tennis for sure."
For her part, Swiatek struck the ball with authority while the contest lasted. Every stroke an explosion, she attacked the lines, cracking five winners and forcing eight errors off the racquet of Tsurenko.
"I felt pretty confident," the top seed told reporters. "So overall, I'm happy with the performance, but of course it's not nice to finish a match like that. So I hope Lesia is going to be okay and she'll recover quickly."