الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Acute otitis media (AOM) is common in infants and
children,many studies have shown that almost all children
experience at least one episode of the disease in the first years
of life, and that up to 50% suffer from recurrent
episodes(Armengol et al.,2011).
In most cases, AOM spontaneously disappears or evolves
favorably when treated with antibiotics, but it can occasionally
give rise to troublesome problems, such as tympanic
membrane perforation, or serious complications, such as
mastoiditis, meningitis or brain abscesses(Vergison A et
al.,2010). Because of its very high absolute frequency and risk
of complications, AOM has substantial medical, social and
economic consequences(Wolleswinkel-van den Bosch et
al.,2010).
Moreover, as most cases are treated with antibiotics(Halasa et
al.,2004), AOM is considered one of the most important
causes of the emergence of microbial resistance. For all of
these reasons, the prevention of AOM is widely
advocated(Morris and Leach ,2009).
Together with other preventive measures, the use of vaccines
could lead to a significant reduction in the incidence of the
disease (Morris and Leach ,2009). This assumption is based on an evaluation of the etiology of AOM, which includes some
infectious agents for which effective and safe vaccines are
available. Although approximately two-thirds of the cases of
AOM are caused by bacteria, almost all of the episodes are
preceded by an upper respiratory viral infection that plays a
fundamental role in the pathogenesis of the disease
(Chonmaitree et al.,2008).
Moreover, respiratory viruses can be cultured from the middle
ear fluid of up to 30% of children with AOM( Yano et
al.,2009). Although several respiratory viruses, including
respiratory syncytial virus, are more frequently associated with
AOM, a relevant number of influenza cases every year are
complicated by the development of this disease (Esposito et
al.,2005), and in most of them, influenza viruses are identified
in the middle ear fluid( Wiertsema et al.,2011). It has
therefore been suggested that the vaccine prevention of
influenza may have a favorable effect on the incidence and
course of AOM, and various experts have supported its use as
a means of reducing the risk of AOM, particularly in otitisprone
children( Marchisio et al.,2010). Moreover, as
Streptococcus pneumoniae is one of the leading AOM
bacterial pathogens( Vergison, 2008), and it has been
repeatedly demonstrated that the influenza virus alters the
respiratory mucosa in a way that predisposes to adherence,
invasion and induction of disease by pneumococcus
(McCullers, 2006), this has been considered a further reason for the administration of influenza vaccine to prevent AOM.
Finally, independently from a previous influenza infection,
because the administration of pneumococcal conjugate vaccine
(PCV) is capable of inducing a significant immune response
even in younger children (i.e., those with the highest incidence
of AOM), it has been supposed that its use could be per se a
possible means of reducing the incidence of AOM and its
related problems( Rodgers et al.,2009).
However, although a number of studies have measured the
impact of both vaccines on AOM, it is still not known whether
(and to what extent) they are really effective, nor what impact
the more recently licensed vaccines may have. The aim of this
review is to examine the clinical impact of vaccinations on
AOM.