Leading British scientist Jeremy Farrar is set to leave his leadership role at the UN health agency at the end of September.
Jeremy Farrar, WHO assistant director general for health promotion, disease prevention and care, is set to step down at the end of September as he reaches retirement age, a spokesperson of the UN health agency told Geneva journalists on Tuesday. The statement rectifies reports by the UK newspaper The Telegraph that Farrar had resigned after becoming “increasingly frustrated with the organisation’s internal politics and bureaucracy”.
Without commenting on Farrar’s relationship with the organisation, the spokesperson said the renowned British scientist, 64, was reaching retirement age at the end of next month and that was the reason for his departure.
After a decade leading the health charity Wellcome Trust and advising the UK government during the Covid-19 pandemic, Farrar joined the WHO as chief scientist in 2023. In May 2025, he was promoted to assistant director general as part of a major overhaul that cut the number of programme divisions from 10 to four and shrank the senior leadership team.
Dr Bruce Aylward, a Canadian physician and epidemiologist who previously served as WHO assistant director general for universal health coverage, will take over the role, the spokesperson said. Aylward, who helped steer the WHO through the Covid-19 pandemic, was among those asked to step aside from the leadership team during last year’s shake-up.
Farrar’s departure comes at a fragile time for the WHO. Following the United States’ withdrawal and abrupt funding halt in 2025, the agency has undertaken its biggest downsizing yet, cutting 2,400 jobs, including 900 in Geneva. The announcement also comes as the Democratic Republic of the Congo struggles to contain its deadliest Ebola outbreak on record, and as the race heats up to find a successor for WHO director general Tedros Adhanom Ghebreyesus, whose term ends in 2027.
Farrar told Politico in June he had “no intentions” to run for the top UN health role amid speculation that he was among the profiles being considered.