Ms Webster, the former Sky Sports News presenter who this year hosted ITV’s Tour Series cycling race, became unwell on 6 August after watching the Olympic opening ceremony, reported the Independent.
The 33-year-old from Sheffield was admitted to hospital where doctors thought she was dehydrated following her gruelling six-week ‘Ride to Rio’ challenge.
However her condition deteriorated after developing a “severe complication from a bacterial infection,” according to a message posted on her Twitter account.
She may have contracted a rare strain of Malaria and has been put on life support, reported the Sun.
Ms Webster had cycled 1,600 miles from Recife in the north east of the country to Rio de Janeiro in 39 days with the widower of breast cancer fundraiser and athlete Jane Tomlinson, who died in 2007.
— Charlie Webster (@CharlieCW) August 9, 2016
However Ms Webster made no more posts and a statement on her Facebook and Twitter profiles on 11 August revealed how her condition had worsened.