Leicester (10) 20
Tries: Murphy, Mauger Cons: Flood (2) Pens: Flood (2)
Newcastle (0) 3
Mauger scored Leicester's second try after 65 minutes
Leicester did enough to see off a depleted Newcastle side thanks to tries from Geordan Murphy and Aaron Mauger.
Toby Flood kicked a penalty before setting up Murphy's try as the Tigers edged into a 10-0 lead at half-time.
Newcastle, who lost several players to a virus, managed to get on the scoreboard with a Steve Jones penalty.
But any hopes of a comeback were quickly ended when All Blacks centre Mauger piled over for a converted try and Flood duly kicked the extras.
Leicester had started the game sluggishly and Newcastle wasted a chance to take advantage when Rob Miller was wide of the posts with his penalty kick.
The home side finally broke down the Falcons' defence only for Lewis Moody to be denied a try by Tom May's late tackle.
Flood finally found a way through for Leicester as he passed the ball to Murphy, who touched down in the corner on 34 minutes.
Things got worse for Newcastle when scrum-half Hall Charlton went off with a back injury just after half-time.
Mauger soon wiped out Jones' penalty as he held off May to score a second try for Leicester, who never looked like grabbing the two more they needed for the bonus point.
Leicester boss Heyneke Meyer:
"I don't want to make excuses but a lot of the guys are sick.
"There was definite frustration we did not score more tries today.
"At the end of the day we got four points out of the game so it is job well done."
Newcastle boss Steve Bates:
"We were really down to the bare bones - we have got a really long injury list.
"It was a good performance in many aspects but we just did not look after the ball well enough in the first half.
"Coming here and defending like we did at Welford Road is a real credit to lads' commitment and determination."
Leicester: G. Murphy, Hamilton, Smith, Mauger, J. Murphy, Flood, Dupuy, Stankovich, Chuter, White, Wentzel, Kay, Newby, Moody, B. Deacon.
Replacements: Rabeni for Smith (70), B. Youngs for Dupuy (62), Davies for Chuter (53), Castrogiovanni for White (59), Varndell for Wentzel (41), Herring for Moody (64).
Not Used: Corry.
Newcastle: May, Visser, Davey, Tu'ipulotu, Rudd, Miller, Charlton, Golding, Thompson, D. Wilson, Swinson, Sorenson, Williamson, B. Wilson, Dowson.
Replacements: Dillon for Davey (70), Jones for Miller (55), Grindal for Charlton (45), Ward for Golding (48), Vickers for Thompson (70), Perry for Sorenson (72), Parling for Williamson (57).
Ref: Tim Wigglesworth (RFU).