Singh, previously a director, becomes MD. Fiona Rollo, who has been at H&K for more than three years, has become consumer health director. She was previously marcoms director.
Singh oversees around 35 staff with clients including AstraZeneca, Roche, Merck Sharp & Dohme, Pfizer and Genosis.
Ilett only joined H&K in a full-time capacity last April, effectively replacing Mike Kan, now UK healthcare MD at Edelman. She had spent the previous couple of months working for the agency part-time. Despite no longer being on the H&K payroll, Ilett is continuing to work for the agency in a minor capacity as a freelance 'senior consultant'.
UK chief executive Marie Louise Windeler said she was 'sad to see her go', and Ilett was unavailable to comment as PRWeek went to press.
H&K's consumer health team was formerly part-managed by joint marcoms MD Wendy Mair – the agency stalwart who left after 16 years last year (PRWeek, 28 October 2005).
Singh was promoted to the London board a year ago. She joined the agency in 2001 and has formerly worked for Ketchum London and Stratis KPR in New York.
Before joining H&K, Rollo was marcoms director at GCI.
Other staff under Singh's aegis include Corinne Pluchino, the senior associate director who joined last year and specialises in PA work, plus senior associate directors Louise Strong and Carrie Monaghan. Charlotte Vereker remains an associate director.
Nick May remains UK health practice chair and head of healthcare across EMEA.