Several of those who tested positive for the virus have since recovered and Flamengo were able to begin Wednesday's match with seven of their usual starters.
There was a hint that the ball could have brushed Jota's arm, but the goal was allowed to stand and Liverpool now have three wins from their first three games of the season.
However, Inter ran riot in the dying minutes as Lukaku found the net from substitute Hakimi's pass, two minutes before Danilo D'Ambrosio scored the winner with a header.
The recent setback is reviving discussions about Favre's ability to create stability while the squad is accused of lacking robustness when facing determined opponents of lower class.
"We have passed a difficult situation to reach the stage and don't want to lose our chance easily. Our players are highly-motivated for this match and are ready for this tough challenge mentally," he said. Enditem
"I'm really pleased with the victory. It's always tough to start the tournament. I was a bit nervous. She played really well in the first set, she didn't miss. Then I just found the rhythm," said the 2018 champion.
However, that goal only served to pique Liverpool and Sadio Mane drew them level with a simple volleyed finish after Leno did well to parry a shot from Mohamed Salah on the break.
Elsewhere, Guangzhou Evergrande sealed the 1-0 win by an own goal from Dalian Pro defender Shan Pengfei.
Real Madrid confirmed with a communique on their official website on Wednesday that the Belgian international has suffered "a muscle injury in his right leg."
The game was over by halftime as the 18-year-old produced a magnificent display that will only give strength to those who see him as the natural successor to Leo Messi.
Messi was the center of attention at the start of the game after his attempt to leave the club over the summer and Friday's criticism of the decision to sell Luis Suarez to Atletico Madrid, but Fati was the hero of the game, scoring in the 15th and 19th minute and then winning a penalty to allow Messi to add a third in a thrilling first half performance.