Attachment 9
PREVENTING MENINGOCOCCAL DISEASE WITH A NEW
VACCINE
PUBLIC HEALTH
IMPORTANCE
Until this year around 250 people died from
meningococcal disease in England and Wales each year, the majority
(over 60 per cent) of these deaths are in young people under the
age of 20. The disease peaks each year in the winter months, with
the rise starting around November and reaching a peak in early
January. As well as the tragic loss of young lives these cases
raise considerable fear and anxiety in the public, especially
when they involve outbreaks.
OPPORTUNITY FOR
HEALTH GAIN
In the UK there are two main types of meningococcus,
serogroups B and C. In recent years a third of all meningococcal
cases have been due to group C, and in those aged 10 years and
over, more than half the cases are due to C. Because C disease
is more severe than B, more than half the deaths, around 150 each
year, are due to C. The first "conjugate" vaccines against
group C went into clinical trial in the US in 1992, and in 1994,
with funding from the Department of Health, the PHLS embarked
on a programme to accelerate their introduction in the UK. In
a co-ordinated series of trials involving infants, pre-schoolers,
school children and university students, the new conjugate vaccines
were found to be safe, to produce protective antibody levels in
almost all recipients and, unlike the existing "plain"
C vaccines, to induce immunological memory—the basis of
long lasting protection. Potentially therefore they could prevent
many deaths over successive years, particularly if introduced
with a catch up programme for all pre-school and school aged children.
ORGANISATIONAL ARRANGEMENTS
In view of the winter peak in cases and deaths,
and with the prospect of licensure of the first conjugate vaccines
in autumn 1999, a decision was taken to introduce them into the
national immunisation programme in a phased manner. The programme
began in November 1999 with immunisation of the highest risk groups,
infants and adolescents, with extension to other age groups as
more supplies became available during 2000. The implementation
strategy was led by the Department of Health with reliance on
PHLS to monitor both the process (ie vaccine coverage by age)
and outcome. The latter required PHLS to establish enhanced surveillance
to monitor the impact on meningococcal disease and to establish
the efficacy and safety of the vaccine under conditions of routine
use. High quality post licensure surveillance data is particularly
important for this vaccine as the UK is the first country to use
it. At considerable speed, the PHLS and collaborators, notably
those of the Institute of Child Health (London), developed a detailed
surveillance plan and protocol for the investigation of vaccine
failures. Such a surveillance programme requires considerable
co-ordination as the contributors include paediatricians who may
see children with meningococcal disease, NHS and PHLS microbiologists
who receive specimens from suspected cases, consultants in communicable
disease control as well as the national reference and surveillance
centres of the PHLS
CONCLUSION
Preliminary findings indicate that the vaccine
has been highly successful. Cases in the two targeted age groups
have dramatically fallen compared with previous years, with so
far only one vaccine failure identified. In the first three months
of 2000 there were only 10 cases of meningococcal disease in one
and two-year-olds compared to an expected 37 based on previous
years' figures. For 15 to 17-year-olds the number observed was
16 compared to the 70 that were expected.
REFERENCE
Communicable Disease Surveillance Centre. Meningococcal
disease falls in vaccine recipients. CDR Weekly 2000; 10: 133,6.
Prepared by Drs Liz Miller CDSC and Ed Kaczmarski
(PHLS Meningococcal Reference Laboratory).
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