The O's surrendered their 100 per cent record when they were held to a 1-1 draw by Walsall on Saturday.
"There were one or two struggling," said Slade.
"Shaun had a virus, he was very sick for 48 hours. Jayden Stockley had a fitness test in the morning and Scotty was 50-50 with a hip injury.
"But they are a good group, they put themselves up and they wanted to get out there."