6 months or more (Criterion E), which helps distinguish the disorder from transient fears
that are common in the popu lation, particularly among children. However, the duration
criterion should be used as a general guide,  with allowance for so me degree of flexibility.
The specific phobia must cause clinically sign ificant distress or impairment in social, oc-
cupational, or other important areas of functioning in order for the disorder to be diag-
nosed (Criterion F).
Associated Features Supporting Diagnosis
Individuals with specific phobia typically experience an increase in physiological arousal
in anticipation of or during exposure to a phobic object or situation. However, the physi-
ological response to the feared situation or object varies. Whereas individuals with situa-
tional, natural environment, an d animal specific phobias are likely to show sympathetic
nervous system arousal, individuals with bloo d-injection-injury specific phobia often
demonstrate a vasovagal fainting or near-faint ing response that is marked by initial brief
acceleration of heart rate an d elevation of blood pressure followed by a deceleration of
heart rate and a drop in blood pressure. Curr ent neural systems models for specific phobia
emphasize the amygdala and related structures, much as in other anxiety disorders.
Prevalence
In the United States, the 12-month community prevalence estimate for specific phobia is
approximately 7%–9%. Prevalence  rates in European countrie s are largely similar to those
in the United States (e.g., about 6%), but rate s are generally lower in  Asian, African, and
Latin American countries (2%–4%). Prevalence  rates are approximately 5% in children and
are approximately 16% in 13- to 17-year-olds. Prevalence rates are lower in older individ-