A salmonella outbreak has affected numerous fly-in, fly-out workers at Rio Tinto's iron ore operations in Western Australia's Pilbara region, prompting an investigation into the source of the infection.

The outbreak occurred across several accommodation villages servicing the Brockman 4 mine and the nearby Brockman Syncline 1 development, where workers began reporting gastroenteritis-like symptoms.

Rio Tinto activated an outbreak response after an increase in reported illnesses, with medical testing confirming salmonella infections among affected workers.

The Western Australian Department of Health was notified, although the source of the outbreak had not been established as of 6 October 2026.

Initial water testing returned clear results, while food samples had not provided conclusive evidence of contamination. Salmonella infections are commonly associated with contaminated food, including improperly cooked poultry and eggs.

Rio Tinto declined to confirm the number of workers affected. The Brockman operations employ almost 2,000 people across their mining and construction activities.

Additional cleaning, disinfection and hygiene measures were introduced at affected accommodation facilities, with sick workers receiving support and being placed in isolation where necessary.

The company reported that the number of workers remaining unwell or in isolation was declining.

The outbreak has also placed attention on Sodexo, the international catering and facilities management company responsible for food preparation and cleaning services across Rio Tinto's Pilbara operations.

Sodexo confirmed that it was working with Rio Tinto to investigate the infections and had introduced additional hygiene measures.

One of the affected accommodation facilities was West Pilbara Village, which had previously experienced problems with mould contamination earlier in 2026.

Sodexo has managed Rio Tinto's Pilbara catering and cleaning services since 2016, initially securing a ten-year contract valued at approximately $2.5 billion.

In May 2026, Rio Tinto renewed the arrangement for at least another seven years, covering services for approximately 20,000 workers across its Pilbara iron ore operations.

The outbreak comes amid continuing efforts by Rio Tinto to reduce operating costs across its iron ore business.

Investigations into the source of the salmonella infections remained ongoing, with no confirmed link established between the outbreak and a particular food item, water supply or service provider.