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The Blues lead the top flight with 59 points with 14 games remaining.
Second-placed Tottenham lead the chasing pack with 50 points, and just five points separate them in second and Manchester United in sixth.
"I think there are six teams who are very strong and can fight to win the title," said Conte.
Third-placed Manchester City, Arsenal, in fourth, and fifth-placed Liverpool make up the top six.
"Manchester United? Yes. They have a great squad," added Conte.
"There are 14 games to play and five teams as well as us who can fight to win it. It's important we don't make mistakes in the race."
Chelsea face a trip to Burnley on Sunday for a 13:30 GMT kick-off. The Clarets have won their last seven games at home in all competitions with 28 of their 29 league points so far this season coming at Turf Moor.
"There are teams at the bottom who win and draw so you must have the right concentration," said Conte.
"If your ambition is to stay in the top four or top six, you can have highs and lows.
"If you want to win [the title] you must have concentration and focus and know that in every game you can lose points."
Chelsea manager Antonio Conte says it would be a "very big mistake" for his side to think they are close to winning the Premier League title.