Mike Brown suspects the septicaemia that forced him to miss the start of the season may have been the result of the punishment absorbed during England’s summer tour of Australia.

Brown sat out Harlequins’ first two matches of the new Aviva Premiership campaign after being confined to hospital by the potentially life-threatening blood infection, but has now been passed fit to make his comeback against Exeter on Saturday.

The 31-year-old full-back spent five days under medical supervision and lost 6kgs, forcing him to feast on as many calories as possible in an attempt to regain what he had shed. Although the cause of the infection is unknown, Brown said starting all three Tests in the 3-0 series whitewash left him battered and bruised.

“I woke up one morning with a pain in my shoulder. I thought it was just a bang in training then I started feeling quite ill and was sent for an MRI and blood tests,” Brown said. “I ended up in hospital for five days with septicaemia. I was cold, with shivers and bug symptoms, and my shoulder pain was getting worse and worse. My haemoglobin was down, white blood cells down, liver down.

“I had no lacerations or bites or anything. It could have been a trauma from the Australia tour – I was quite bruised. It’s been good because I’ve been able to eat what I want. To start with I was eating anything.

“Coming back, you have to take it step by step and see how you react because the body systems take a bit of a hammering. To start with I didn’t really know what was going on. It was frustrating because I’d done four weeks of really hard training.

“My weight was still down last week but I’m ready to go now. Playing rugby is what I’m about.”

It took a huge effort from England to complete an unexpected 3-0 series victory over the Wallabies with players who had looked out on their feet at the final whistle in Melbourne stirring themselves for one final assault.

Brown, who married his partner Eliza during the summer, believes the Sydney finale, won 44-40, is evidence of the character in the team but views the Grand Slam and success Down Under as merely staging posts.

“I was absolutely hanging before the last game. Ten minutes before the end I’d taken a couple of kick-offs straight down the middle and took a bit of a beating on the floor,” he said. “I was hanging on a bit at the end but, although it had been a 13-month season, it was the best game we played there.

“To do that in the last Test when we had already wrapped up the series when we could easily have gone ‘nah, we’ve won the series, we’re on holiday’ shows what this group is about.

“But it’s only a start with England. If you look at it, we haven’t really achieved much. Achieving things is when you start winning multiple grand slams, beating southern hemisphere teams all the time, being No1 side in the world and winning multiple World Cups.

“It’s a good start and we’ve got to use it as a stepping-stone. There’s more pressure on us now and more teams that want to knock us down.”