Toby Flood ran the show against his former club Newcastle as Leicester inflicted the Falcons' fifth straight Premiership defeat. The fly-half moved to Welford Road from Newcastle in the summer and contributed 10 points with the boot as well as setting up Geordan Murphy for the game's opening try.
Centre Aaron Mauger grabbed the Tigers second score after 65 minutes but Leicester were far from their rampaging best without rested England stars Tom Croft, Jordan Crane, Dan Hipkiss and the suspended Harry Ellis. Newcastle's only points came from replacement Steve Jones' second-half penalty but they battled gamely with a number of their players suffering from a virus.
Fly-half Rory Clegg and Adam Balding were ruled out by the bug but it was Tigers who started sluggishly with both teams engaged in a kicking game during the early stages. Newcastle wasted a golden opportunity to take a surprise lead when 18-year-old Rob Miller was wide of the posts with a penalty after 14 minutes.
It was not until midway through the first half that Tigers began to find their stride with Flood being smothered just short of the tryline by some desperate Newcastle defending. However, it was not long until they made their pressure count through Flood's well-struck penalty after 22 minutes.
Six minutes later, they were unlucky not to score the game's first try after a terrific phase of play. Lewis Moody was given space to run into after fine work by Flood and Mauger only to be denied by a full-back Tom May's try-saving challenge.
The Tigers continued to turn the screw and they did score the game's opening try in the 34th minute with Flood again at the heart of the action. In a sweeping move from right to left the 23-year-old's astute pass put Ireland star Murphy over in the corner.
Flood's conversion from a tight angle saw the Tigers head into break 10-0 up. Leicester boss Heyneke Meyer threw on Martin Corry and Tom Varndell as the home side looked to build on their advantage.
Flood added a second penalty in the 49th minute after John Rudd was penalised for holding on. Newcastle boss Steve Bate's injury woes then increased when scrum half Hall Charlton hobbled off with a back injury, although he did watch his team get themselves on the board in the 59th minute thanks to replacement fly-half Jones' penalty.
But any hopes of a comeback were swiftly dispelled when Leicester got their second try six minutes later. Replacement Ben Youngs made ground before fizzing a pass to Mauger who held off May's tackle to pile over for a converted try.
The Tigers never looked like grabbing two further tries for the bonus point although Flood did set off on a jinking run from inside his own half before miscuing his pass to Youngs on the Newcastle.
Leicester boss Heyneke Meyer was disappointed that his side could not wrap up a bonus-point against the struggling Falcons.
"I don't want to make excuses but a lot of the guys are sick," he said. "A lot of them have been coming off and coughing up sick so it has been a really difficult day for the guys. At the end of the day we got four points out of the game so it is job well done.
"Toby Flood is playing good rugby at the moment. He did well for England and he did really well today in what was a difficult game. There was definite frustration we did not score more tries today. We had enough chances to score and finish today and probably should have scored two more tries but we didn't."
Steve Bates' Newcastle side has also suffered with illness this week, with fly-half Rory Clegg and flanker Adam Balding added to their already lengthy injury list by the bug.
"Some of the guys have been suffering a bit today. We were really down to the bare bones - we have got a really long injury list," Bates said. "It was a good performance in many aspects but we just did not look after the ball well enough in the first half. We made a few more tackles than they did today but we are in and rebuilding process here at the moment.
"Coming here and defending like we did at Welford Road is a real credit to lads' commitment and determination. The way they fought was outstanding. We did really well in the opening 60 but their second try just came at the wrong time."
Leicester: G. Murphy, Hamilton, Smith, Mauger, J. Murphy, Flood, Dupuy, Stankovich, Chuter, White, Wentzel, Kay, Newby, Moody, B. Deacon
Replacements: Davies, Castrogiovanni, Corry, Herring, B. Youngs, Varndell, Rabeni.
Newcastle: May, Visser, Davey, Tu'ipulotu, Rudd, Miller, Charlton, Golding, Thompson, D. Wilson, Swinson, Sorenson, Williamson, B. Wilson, Dowson.
Replacements: Vickers, Ward, Perry, Parling, Dillon, Grindal, Jones.