Health experts have warned the UK could be facing its worst outbreak of flu for nine years.
The Royal College of General Practitioners (RCGP) said there has been a 73% increase in the number of people seeing a GP with flu-like symptoms in the past week.
Figures show that for every 100,000 people, doctors are seeing 69 people with flu symptoms, 29 more people than last week.
It also appears the biggest increase is among elderly patients. A 151% has been seen in people aged 65 or over, from 18 people per 100,000 population to 45.
However, the number of people seeing their doctor with flu-like symptoms was greatest in the 15 to 44 age group (80 per 100,000 population), which has risen 47% in the past week.
Douglas Fleming, a director at the RCGP's Birmingham Research Unit, said: "The recent increase is suggestive of an influenza outbreak greater than any seen in the last eight years."
Professor David Salisbury, the Department of Health's director of immunisation, said: "Flu has started earlier this year than last year and the figures show an increase in the number of people consulting their GPs with flu-like illnesses."