Wheldon is to join Manning Selvage & Lee in April as media relations director in its London health team.
News of her imminent switch comes hard on the heels of Daily Telegraph medical editor Celia Hall's unrelated impending move to health specialist Santé Communications (PRWeek, 2 February).
At MS&L, Wheldon will report to UK head of healthcare Peter Carr, who himself only joined late last year (PRWeek, 1 Nov 2006).
MS&L's two major health clients are Sanofi-Aventis and Eli Lilly. Wheldon's main responsibilities will be with the former, working on UK briefs for cancer drug Taxotere and high-profile anti-obesity product Acomplia. She is also likely to provide media advice to non-pharma MS&L staff and clients.
Wheldon joined the Daily Mail just over two years ago from the Daily Express, where she was health editor. Before that she was health correspondent at The Press Association.
At the Daily Mail she is part of a four-strong science and health team, working in tandem with medical correspondent Jenny Hope and reporting to news editor Keith Poole. She will leave on 29 March before starting at MS&L on 10 April.
Wheldon told PRWeek: ‘I wanted a new challenge and to use my skills in a new way. I think a lot of journalists have the wrong view of what PR involves.'
She said she had ‘put feelers out' and went to see a recruitment agency late last year ‘to ask what they would put me forward for'. She said she had subsequently met ‘quite a number' of agencies but immediately ‘clicked' with MS&L personnel.
Carr said MS&L had moved quickly to secure Wheldon's services. He added: ‘December was when most of the talking went on about this. I want high-quality people working for us - and not the competition.'
MS&L's UK health team is around 18-strong, with other senior figures being medical affairs director Guy Nasse and director Jennifer Garratt.
Wheldon, who is 33, started her journalistic career as a news reporter at the Western Morning News in Plymouth.
MS&L last month confirmed the appointment of Hill & Knowlton's Stuart Wilson as its new CEO (PRWeek, 16 Feb).