A lethal form of meningitis is growing rapidly in Britain and is poised to strike scores more victims as the flu outbreak peaks, doctors warned yesterday.

A lethal form of meningitis is growing rapidly in Britain and is poised to strike scores more victims as the flu outbreak peaks, doctors warned yesterday.

Meningococcal septicaemia, a form of blood poisoning caused by the same bacterium as meningitis, is up 21 per cent on a year ago according to figures obtained by The Independent, and is claiming over 150 new victims each month.

Septicaemia is the most lethal complication of meningitis and spreads through the bloodstream. Cases have risen threefold in five years and in the worst cases the infection causes rapid organ failure and death, sometimes in hours.

Experts say some of the increase is due to improved testing but consultant paediatricians are reporting a sharp rise in cases of children with septicaemia.

Meningitis tends to surge in the weeks after a flu outbreak because more people have inflamed throats as a result of their illness, providing a ready route for entry of the bacterium.

Latest flu figures published yesterday show the rate has risen to 203 cases per 100,000 population, above the normal winter level of 50 to 200 cases per 100,000.

Cases of meningitis and septicaemia, collectively known as meningococcal disease, reached their highest levels since the Second World War in 1998 but are continuing to soar. Provisional figures for 1999 from the Government's Public Health Laboratory Service show there were 2,973 notifications of the disease, up 12 per cent on 1998. Cases of septicaemia rose to 1,828, up by 319 cases (21 per cent) on 1998. In 1994 there were 430 cases of septicaemia.

Specialists in infectious disease say meningitis, which strikes the young and fit with unnerving speed and ferocity, has changed and become more virulent. The group c strain of the disease which is more common in older children and teenagers has been growing since the mid 1990s and has a higher death rate. Figures for deaths in 1999 are not available but in 1998 the group c strain claimed 210 lives.

A new vaccine against meningitis c was introduced on 1 November and it is planned to cover all 14 million of the population aged up to 18 by the end of 2000. Cases for this winter are already lower than last although experts are uncertain whether that is the effect of the vaccine or the natural cycle of the disease.

The Meningitis Research Foundation said the rise in cases of septicaemia was the most worrying development. A spokeswoman said: "If you ask any consultant who treats children in hospital the number of cases referred to them is hugely increased with a much greater frequency of septicaemia. There is better reporting but there is also a change in the disease."

Dr Mary Ramsay, consultant at the Public Health laboratory Service said: "There has been a nastier bug around for the last few years and there is no doubt there is more meningococcal disease. We keep waiting for it to peak and go away but it hasn't yet."

Professor Robert Booy, professor of child health at the Royal London Hospital, said: "We have had more patients with meningitis and septicaemia referred in the last two weeks than in the previous two months. It is part of the seasonal surge but flu will have contributed to that."

The UK has the second highest rate of meningococcal disease in the western world after the Republic of Ireland, but the reasons are not understood. The total cases in the UK are approximately equal to those in the US, a country with ten times the population.

The Meningitis Research Foundation, in Thornbury, Bristol, has received a donation of £250,000 from Dyson makers of the vacuum cleaner, to fund research but is lacking worthwhile proposals from scientists to spend it on. A spokeswoman said: "We have never received a donation as large as this. There must be scientists desperate for funding whom we could help." Meningitis Research Foundation 0808 800 3344 (24 hour helpline)