There is an additional peak in incidence, reaching nearly 1% per year, during old age in both men and women, possibly reflective of newly occurring physical conditions or adverse life events. The development of phobias varies with subtypes, with animal and blood injection phobias typically beginning in childhood (ages 5–12), whereas development of situational specific phobias (i.e., fear of flying) usually occurs in late adolescence and early adulthood.In the US, the lifetime prevalence rate is 12.5% and a one-year prevalence rate of 9.1%. An estimated 12.5% of U.S. adults experience specific phobia at some time in their lives and the prevalence is approximately double in females compared to males. An estimated 19.3% of adolescents experience specific phobia, but the difference between males and females is not as pronounced. See also
List of phobias
Phobia

References
External links
Encyclopedia of Mental Disorders – Specific phobias
Cluttons joints is a term describing the finding of symmetrical joint swelling seen in patients with congenital syphilis. It most commonly affects the knees, presenting with synovitis and joint effusions (collections of fluid within the joint capsules) lasting up to a year. It has also been reported affecting the ankles, elbows, wrists and fingers. It is usually painless, although pain in the absence of trauma can occur in a few cases. There is usually no disability associated with the joint swelling, and recovery is usually complete. It occurs between 5 and 20 years of age in both sexes.The condition was described in 1886 by Henry Hugh Clutton in The Lancet. == References ==