Bournemouth scored a 2-0 win over Southampton at the Vitality Stadium on Tuesday night.
The opener came in the 31st minute when Matt Ritchie sent in a free-kick from the right which fell for defender Cook to acrobatically send a volley bouncing past Fraser Forster for his second goal in the Premier League.
Bournemouth added a second just over 10 minutes from time when Ritchie's floated set-piece invited Afobe to work his way to the front and head home for his fourth in eight league appearances since arriving from Wolves in January.
The win has the Cherries sitting 15th on the table, eight points clear of the drop zone, while Ronald Koeman's Saints drop to seventh having lost their past two after going six matches without conceding.
Vitality Stadium, Bournemouth - 11,033
- Will Bournemouth start to move away from the relegation mire now? If they do stay up, how big an achievement is that for the club?
- Southampton seem to have a big gap between their best and their worst but is their best good enough to really worry the top five or six?
Bournemouth head to relegation-threatened Newcastle on Saturday as the Saints prepare to host Sunderland who are also involved in a relegation battle.
Huge win tonight! Lads were outstanding!
— Steve Cook (@SteveCook28) March 1, 2016
Great win last night. Fans were brilliant! Looking forward to another important game this weekend
— charlie daniels (@chazdaniels13) March 2, 2016
Bournemouth boss Howe on the significance of the win:
"It feels like a really big night for the club, beating our local rivals," Howe said. "For our survival hopes it's a massive result as well.
"Our destiny even before the game was in our hands. We certainly have that attitude: we can't rely on other teams to slip up.
"We need to attack things and try to get there ourselves."
Southampton's Koeman on the disappointing performance:
"We had more ball possession in the second half but we didn't create really big chances.
"It's not good enough. It's always disappointing if the opponent is hungrier than your team."