Liverpool are set to be without Dutch centre back Van Dijk for a lengthy period as he requires surgery after damaging his knee ligaments in the Merseyside derby last weekend.
However, ahead of United's league trip to Liverpool on Saturday, Wilder addressed his own injury issues.
Blades defender Jack O'Connell is likely to miss the rest of the season with a knee injury, while forward Lys Mousset (toe) and midfielder John Fleck (back) are weeks away from making a comeback.
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"We are hoping to get Lys back on the grass, that's about six to eight weeks away, while John Fleck will hopefully be back next month," Wilder told a news conference on Thursday. "Jack O'Connell probably out for the season too.
"Us losing these three players is, I'd say, a bigger loss than losing Van Dijk, relatively."
Liverpool's Fabinho moved from midfield to centre defence and delivered an assured display as they beat Ajax Amsterdam 1-0 win away in their Champions League group-stage opener on Wednesday.
"They still have world-class players and an academy that produces players all the time," Wilder said. "And those three at the top of the pitch (Mohamed Salah, Sadio Mane and Roberto Firmino) can hurt anyone.
"Their performance levels didn't dip last night and I'm not expecting it to on Saturday."
Wilder hinted at record signing Rhian Brewster making his first start for Sheffield United against his former club.
The 20-year-old striker, who arrived at Bramall Lane earlier this month, made his first appearance for Wilder's side as a second-half substitute in a 1-1 draw with Fulham last weekend.
United are winless and second-bottom in the league table after five matches, while Liverpool sit third with 10 points. (Reporting by Hardik Vyas in Bengaluru Editing by Toby Davis)
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