Impact of the meningococcal C conjugate vaccine in Spain: an epidemiological and microbiological decision.
The new meningococcal C conjugate vaccine became available in Spain and was included in the infant vaccination schedule in 2000. A catch-up campaign was carried out in children under six years of age. As a consequence, the incidence of meningococcal disease caused by serogroup C has fallen sharply during the last three epidemiological years in Spain. The risk of contracting serogroup C disease in 2002/2003 fell by 58% when compared with the season before the conjugate vaccine was introduced. There was also an important decrease in mortality. Three deaths due to serogroup C occurred in the age groups targeted for vaccination in 2002/2003, compared with 30 deaths in the same age groups in the season before the launch of the vaccine campaign. In the catch-up campaign the vaccine coverage reached values above 92%. For the 2001, 2002 and 2003 routine childhood immunisation programme coverage values ranged from 90% to 95%. During the past three years a total of 111 cases of serogroup C disease have been reported in patients in the vaccine target group. Most of the vaccination failures occurred during the epidemiological year 2002/2003. Eight (53%) vaccine failures occurred in children who had been routinely immunised in infancy, and could be related to a lost of protection with time since vaccination. The isolation of several B:2a:P1.5 strains (ST-11 lineage) is noteworthy. These may have their origin in C:2a:P1.5 strains which, after undergoing genetic recombination at the capsular operon level, express serogroup B. These strains could have relevant epidemic potential.
Cano
R
R
Centro Nacional de Epidemiología, Instituto de Salud Carlos III, Madrid, Spain.
Larrauri
A
A
Mateo
S
S
Alcalá
B
B
Salcedo
C
C
Vázquez
J A
JA
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D032541:Mass Vaccination; D008585:Meningitis, Meningococcal / Q000453:epidemiology* / Q000517:prevention & control*; D022401:Meningococcal Vaccines / Q000627:therapeutic use*; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011159:Population Surveillance; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012621:Seasons; D013030:Spain / Q000453:epidemiology; D016896:Treatment Outcome; D014611:Vaccination / Q000706:statistics & numerical data*
D022401:Meningococcal Vaccines; C410218:serogroup C meningococcal conjugate vaccine