A deadlier form of meningitis

The British government has touted Neisseria meningitidis group C as the most deadly bacterium causing meningococcal disease, which affected 1,530 people in Britain last year and claims the lives of one tenth of those who contract it.

But not according to the DoH's own "factsheet". Group C meningococcal disease, which began appearing only a decade ago, accounts for only 40 per cent of cases of meningitis contracted in Britain and elsewhere. Between 1994-9, meningitis B killed nearly 70 infants under one. This incidence represents more than three times the number of deaths of meningitis C among this age group during the same period. Strain B also killed twice as many one year olds as did strain C. In all, meningitis B killed approximately 170 children under six which represents the same number of deaths from meningitis C among all age groups combined. Although meningitis C is the major cause of meningococcal death among teenagers, accounting for 80 per cent of deaths (meningitis B only claimed the lives of about 24 teenagers and young adults), the B version is far more deadly to babies and small children, representing at least two thirds of all meningococcal deaths in this age group.

David Hall, corporate affairs manager for Wyeth, who developed the new vaccine, says that so far, producing a vaccine for the B strain has proved elusive. "B has structural differences, having to do with one of antigens on the polysaccharide protein code," he says. "For some reason, that makes it difficult to come up with a workable vaccine."

Dr Richard Nicholson, editor of the Bulletin of Medical Ethics, is concerned that even if this vaccine proves 100 per cent effective, it will protect against only a minority of meningococcal cases. Nevertheless, its existence could cause the public to become complacent about watching for warning signs of the disease caused by the other strains.

Immunity for life?

This vaccine will offer teenagers "almost 100 per cent immunity for life", wrote the Times, and the DoH confirms that besides babies, who will get three doses, a single dose is sufficient in all other children. In the very first edition of What Doctors Don't Tell You, we quoted then health minister Edwina Currie claiming that the new triple measles, mumps, rubella (MMR) vaccine would offer "life long protection with a single jab". Five years later, the British government launched the countrywide booster campaign, after massive epidemics of measles among previously vaccinated youngsters in America proved that the MMR does not, after all, give you protection for life.

If the meningitis vaccine works similarly and most vaccines appear to wane over a decade then teenagers and young adults vaccinated as babies and toddlers will experience waning immunity just at a point where they are most vulnerable to the disease.

Besides not knowing how long this vaccine will last, no one is sure how many shots and of which variety will confer long term protection.

In one study of 114 infants from West Gloucestershire, babies were randomly divided into groups receiving either a 2 mcg or 10 mcg dose of meningococcal C vaccine. Then, half the infants received the old A and C polysaccharide vaccine at 15-20 months. (The others were to receive this booster at age 4.)

Among those getting the lower initial dose, bactericidal antibody titres rose at five months but fell by 14 months to not much higher than they were originally (1: 4 to 1:1057 to 1: 19). With those receiving the 10 mcg dose, antibody responses were significantly higher at five months than in the 2 mcg group, but were lower after boosting with the plain polysaccharide vaccine than with the lower dose group.