The ex-Watford forward has been unable to train since Swansea's 2-1 win over Newcastle, and was not in the matchday squad for Sunday's draw with Liverpool. Swans manager Michael Laudrup has confirmed the 27-year-old will also miss out against the Baggies after failing to recover from an illness that also affected some of his team-mates.
The forward's inability to train means he is also unlikely to be involved in Saturday's trip to face Arsenal, and Laudrup said: "He is not available. We really don't know (what it is). He has been sick for nearly a week now, he doesn't feel well and he has been feeling dizzy."
He added: "We have had three or four players with that, but they are all back in training, but Danny is still ill so he is ruled out for the game tomorrow."
Luke Moore, one of those to suffer with the illness, is back in contention against one of his former clubs, but Jonathan de Guzman is a doubt. The Swans' goalless draw with Liverpool moved them up to ninth in the table, but Wednesday's opponents continued their superb start to the season with a 4-2 win at Sunderland.
Steve Clarke's side have been the surprise package of the season to date and have claimed the scalps of Chelsea and Liverpool along the way.
But Swansea have lost just once at home so far this season, and Laudrup hopes they can keep that run going and move themselves onto a tally of 20 points, and halfway to reaching the oft-stated survival total of 40, before the end of November.
He said: "We know it is going to be difficult but we will go out and play like we always do. We are confident as well, we have only lost one game at home and we don't want to lose any more. We know we have to be strong at home and get most of our points here.
"In the last two home games we have played two big sides in Liverpool and Chelsea and now we play West Brom, the surprise of the season. We want the three points to extend this good moment in terms of points and performances and to get on.
"Every time you get three points you tot them up and it would be so important to reach 20 points as it is halfway to the magic number of 40, and then you can look how many games are left. If we could reach halfway already after 14 games I would be very happy."
Source: PA
Source: PA