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.
Centro Nacional de Epidemiología, Instituto de Salud Carlos III, Madrid, Spain.
R
R
Cano
A
A
Larrauri
S
S
Mateo
B
B
Alcalá
C
C
Salcedo
J A
JA
Vázquez
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