A hospital has reintroduced face mask rules in a number of departments amid a rise in flu cases.

Chesterfield Royal Hospital NHS Foundation Trust announced on Tuesday that staff, patients, and visitors were being asked to wear masks with “immediate effect”.

The mandatory rule has been applied to the hospital’s emergency department, wards and other areas where patients are admitted.

Krishna Kallianpur, chief nurse at Chesterfield Royal Hospital, said: “We have not taken this decision lightly, but the rise in flu cases has meant we needed to take action to promote safety for our patients and colleagues.”

The move comes after the UK Health Security Agency said the winter flu season had begun five weeks earlier than usual.

The organisation said cases were rising quickly among children and young people and warned the virus would soon start to spread across older age groups.

The same mask rule was introduced at Chesterfield Royal Hospital last December.

Ms Kallianpur added: “We are urging our patients and community to support us with this – and to take up the option of a vaccine.”