A major leadership shake-up is rocking the WHO, with two assistant directors-general, Dr Jeremy Farrar and Dr  Yukiko Nakatani, leaving the organisation in quick succession.

For now, Dr Bruce Aylward will take over Farrar’s role while Dr Sylvie Briand will step in for Nakatani. Moreover, following allegations of corruption against Saima Wazed, the regional director for South-East Asia, Dr Nilesh Buddha has taken over as Officer-in-Charge, replacing Dr Caterina Boehme, another former WHO ADG who is leaving the Organization for the UN Population Fund (UNFPA).

The highly respected British scientist Dr Jeremy Farrar unexpectedly stepped down from his post as Assistant Director-General (ADG) for Health Promotion, Disease Prevention and Care at the World Health Organization (WHO).

He is leaving the organisation effective 30 September, according to an internal note by Dr Tedros Adhanom Ghebreyesus seen by Health Policy Watch.

“On behalf of the entire Organization, I extend my sincere thanks to Dr Farrar for his service to WHO and to global public health,” Tedros wrote in the communication.

Farrar’s influential unit was established as part of a major structural overhaul that consolidated 10 previously independent headquarters divisions into four central pillars.

Prior to this, the British scientist headed the renowned Wellcome Trust for almost 10 years before joining the WHO as Chief Scientist in 2023.

Most recently, Farrar was also discussed as a possible successor to Tedros in the upcoming WHO leadership race for the next Director-General. However, he dismissed these speculations.

WHO emphasises usual proceeding

While the internal email from Tedros announced Farrar’s departure as a retirement, insiders and media reports characterised the sudden exit as a resignation.

When asked by Health Policy Watch about the circumstances of Farrar’s departure at a press briefing on Tuesday, the WHO described it as a usual proceeding.

“Dr Farrar is reaching WHO retirement age at the end of next month. So that’s why he is retiring at the end of September,” a WHO spokesperson said.

However, experts maintain that there has been flexibility regarding the retirement of ADGs in the past. “Retirement age as the reason makes no sense,” said one source on the condition of anonymity. “The reasons could also be political.”

‘Highly controversial’ appointee returns to WHO leadership

Tedros announced that Dr Bruce Aylward will act as successor to Farrar. The Canadian physician and epidemiologist has served the organisation for over 30 years, having previously led the Global Polio Eradication Initiative and directed the WHO’s response to the West African Ebola epidemic.

Several sources described Aylward as “a close confidant” of the current Director-General and claimed the appointment was “highly controversial”. Others pointed to recent conflicts between the two.

Aylward lost his previous post as ADG for Universal Health Coverage in May 2025. He had been criticised for being too deferential to China’s handling of the COVID-19 pandemic.

Health Policy Watch reached out to Aylward for comment on Tuesday, but did not receive a response before publication.

Another ADG leaves WHO leadership

In addition to Farrar, the ADG for Health Systems, Access and Data, Dr Yukiko Nakatani, left the WHO on 13 August to return to Japan, according to a spokesperson responding to an enquiry from Health Policy Watch.

Nakatani will take charge of health policy at the Japanese Ministry of Health, Labour and Welfare.

Dr Sylvie Briand, Chief Scientist, will serve as acting ADG, replacing Nakatani until further notice. The French physician has been working for the WHO since 2001 and has over two decades of experience in pandemic and epidemic preparedness.

Insiders attribute the departures of Farrar and Nakatani to deep frustration over Tedros’s leadership. According to these sources, both had recently voiced sharp internal criticism of the WHO’s technical work and data policy.

Neither Farrar nor Nakatani responded to enquiries from Health Policy Watch on Tuesday.

New South-East Asia WHO leadership following corruption allegations

Dr Nilesh Buddha took over as Officer-in-Charge of the Regional Office for South-East Asia (SEARO) on Monday, the WHO announced. He succeeds Boehme, who was WHO’s ADG for External Relations until last year’s budget crisis leading to sharp cuts in WHO’s senior management ranks. Boehme then served a year in South-East Asia, replacing SEARO Regional Director Saima Wazed in July 2025, after Wazed was placed on administrative leave following allegations of corruption and fraud. The charges were brought by the Bangladeshi government against Wazed, daughter of Bangladesh’s former Prime Minister Sheikh Hasina after Sheikh Hasina fled the country in August 2024 following mass protests; some of the charges reportedly stem from Wazed’s initial bid to be appointed WHO regional director.

In late June, it was announced that Boehme is leaving WHO altogether to take a job as Deputy Executive Director with the United Nations Population Fund (UNFPA).

The latest WHO leadership shake-up comes against the background of a deep crisis for the organisation. Following the US withdrawal and massive cuts to official development assistance (ODA), the WHO cut around 25 % of its staff, and pared down its planned 2026-2027 base budget from $5.3 to $4.2 billion – $300 million of which still remains to be funded.

With the WHO DG election race ahead and Tedros’s term of office ending in mid-2027, it remains to be seen what political implications the new leaders bring.

See related story:

First WHO Regional Director Takes Leave To Run for Director-General

Editorial Correction: The original article stated that WHO faces a $1.05 billion budget gap for 2026-2027 – while that gap has now been narrowed to $300 million. The editors regret the error. The article was also updated on 19 August to include additional comments on the leadership transitions.

Image Credits: U.S. Mission Geneva/ Eric Bridiers, Flickr – US Mission Geneva, John Sears, WHO.