This appears to mean that 1) the government believes that boosters will be necessary at some point and is probably already planning for them and 2) nobody really knows which combination of vaccines higher or lower doses for initial shot and follow up boosters is really going to work, or whether using the old polysaccharide vaccine actually lowers your immunity, as it appears to in one study (J Infect Dis, 1999; 179: 1569-72).
The researchers say in the conclusion of their report that "total antibody levels required for protection against serogroup C disease are not known (italics ours).
In another study, also by the PHLS (J Infect Dis, 1996; 174; 1360-3) of a conjugate meningococcal combination A and C product, antibodies also fell rapidly 12 to 14 months later, even after three doses.
Because the antibody levels fell so rapidly, the PHLS addressed itself to what it says is the good news the presence of immunologic "memory". The Hib vaccination, they claim, offers long term protection despite the fact that antibody levels fall rapidly with that vaccine as well. As the Hib vaccine has only been around for a handful of years, time will tell whether that theory is correct.
According to Wyeth's David Hall, the old "polysaccharide" vaccine works at best 75 per cent of the time on older children and wears off after a few years. It does not work in babies and toddlers. The new "conjugated" variety, called Meningitec, has produced immunological "memory" cells in babies and toddlers by being piggybacked onto the diphtheria toxoid, which produces a sort of red alert immune system response (see box, p 1). The existence of these memory cells, he says, means that it's likely the vaccine will last longer, but nobody knows for sure. "We know that this is a sign of long lasting immunity," says Hall, "but until you embark on a mass vaccination programme, you're never going to prove it."
Lucky for Wyeth, then, to be located in Britain. Several years ago, the DoH and its government sidekick, Public Health Laboratory Service, which studies, monitors and formulates immunisation policy, approached Wyeth and other vaccine companies, asking them to step up research into a meningitis C vaccine and even offering to help research it.
When Wyeth got to the finish line first with a product, the PHLS basically took over its testing. Many of the larger trials were conducted by the PHLS.
"One way we were able to bring forward our launch date was because we worked together in collaboration with the DoH," says Hall. Rather than our company having to set up trials, the PHLS did much of the studies for us."
In other words, Wyeth was able to fasttrack this drug through the usual drug approval procedure, which ordinarily requires a drug company to set up its own trials. The government is then supposed to act as an independent judge, approving them on the basis of safety and effectiveness. In this instance, defendant, prosecution, judge and jury were all effectively on the same team.
A further wrinkle on might be labelled a conflict of interest has to do with the monitoring system of the Public Health Laboratory Service. In 1994, the PHLS devised a surveillance system for monitoring side effects of vaccines. This was first tested out with the all country measles booster scheme, leading the cynical to wonder whether the mass measles campaign was manufactured in order to test out the effectiveness of the new system.