Influenza A viruses: Dominant this year

Last week the number of reported cases actually fell slightly - and experts say that numbers so far are not particularly unusual.

Children are hardest hit by one of the most common strains circulating this year, and cases among the young remain slightly on the increase.

However, the half-term break may have hindered the spread of the illness.

So far, a handful of children have died after contracting the Fujian-like strain - three in Scotland and two in England.

The same strain caused a substantial outbreak in Australia, where, at one stage, one in three school-age children were affected.

Over the past few weeks, there had been a swift rise in the number of people seeing their doctor complaining of flu-like illness, particularly in Scotland and the north of England.

Falling away

While, at just over 60 cases per 100,000 people, levels fell far short of being classed a serious flu outbreak, experts monitoring the rise had yet to detect any slowing of the increase, and the rate among younger children, particularly those aged under four, was far higher, at more than 100 cases per 100,000 people in parts of England and Scotland.

We can be encouraged by the check on the increase, but it isn't enough to say that the outbreak is on the turn Dr Douglas Fleming, RCGP

This week the figure dropped slightly to 55 consultations per 100,000 people.

An epidemic is officially classed as anything above 400 cases per 100,000 people in England, or 1,000 per 100,000 in Scotland.

The figure does not reveal exactly how many people have flu, as many do not consult their doctor about it, but simply gives a general guide to levels.

Dr Douglas Fleming, from the Royal College of General Practitioner's research unit in Birmingham, has been monitoring flu in Britain and Europe.

He said: "Flu levels can be highly variable from year to year.

"In the past few years, we have become accustomed to an increase in flu around Christmas, but that is not what always happens."

He said that it was impossible to predict either a large or a small outbreak based on what had happened so far - or the relatively early start to the "flu season".