Invasive pneumococcal disease in children and adults in seven Italian regions after the introduction of the conjugate vaccine, 2008-2014.
OBJECTIVE
To describe the trend of invasive pneumococcal disease in the years 2008-2014; to verify the impact of the conjugate vaccine and monitor the occurrence of serotype replacement.


METHODS
Prospective observational study based on data from the national surveillance for invasive bacterial diseases coordinated by the Istituto superiore di sanità.


METHODS
Seven Italian regions (A.P. Bolzano, A.P. Trento, Emilia-Romagna, Friuli-Venezia Giulia, Lombardia, Piemonte, Veneto), accounting for 43% of the national population.


METHODS
Number of cases and incidence of invasive pneumococcal diseases: global, stratified by age groups and by serotypes included or not in the PCV13.


RESULTS
In 2008-2014, in the 0-4 age group IPD incidence for all serotypes decreased from 7.1 to 2.9/100,000; incidence for vaccine serotypes (VT) decreased from 5.5 to 1.1/100,000, while incidence for non-vaccine serotypes (NVT) increased from 1.6 to 2.0/100,000 (2.5 in 2013). In the >64 age group, IPD incidence increased from 5.3 to 7.5/100,000; VT incidence decreased from 3.9 to 3.2 (4.9 in 2010 and 4.3 in 2013), whereas NVT incidence increased from 1.4 to 4.4/100,000.


CONCLUSIONS
Use of the conjugate vaccine has reduced the number of cases of IPD by VT in children; the increase in IPD by NVT, above all in older age groups, suggests a serotype replacement.
CNESPS, Istituto superiore di sanità, Roma, Italy. dancona@iss.it.
Fortunato
F
D'Ancona
CNESPS, Istituto superiore di sanità, Roma, Italy.
Maria Grazia
MG
Caporali
CNESPS, Istituto superiore di sanità, Roma, Italy.
Martina
M
Del Manso
CNESPS, Istituto superiore di sanità, Roma, Italy.
Cristina
C
Giambi
Dip. Malattie infettive, parassitarie e immunomediate, Istituto superiore di sanità, Roma, Italy.
Romina
R
Camilli
Dip. Malattie infettive, parassitarie e immunomediate, Istituto superiore di sanità, Roma, Italy.
Fabio
F
D'Ambrosio
Dip. Malattie infettive, parassitarie e immunomediate, Istituto superiore di sanità, Roma, Italy.
Maria
M
Del Grosso
Direzione generale della prevenzione, Ministero della salute, Roma, Italy.
Stefania
S
Iannazzo
Direzione generale della prevenzione, Ministero della salute, Roma, Italy.
Elvira
E
Rizzuto
Dip. Malattie infettive, parassitarie e immunomediate, Istituto superiore di sanità, Roma, Italy.
Annalisa
A
Pantosti
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D011008:Pneumococcal Infections / Q000453:epidemiology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines; D011159:Population Surveillance; D011446:Prospective Studies; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000302:isolation & purification; D018074:Vaccines, Conjugate; D055815:Young Adult
C538862:13-valent pneumococcal vaccine; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate