Prevalence and Incidence of Williams Syndrome
Prevalance of Williams Syndrome:
estimated 1 per 7,500 - 20,000 people suffer from Williams syndrome, Genetics Home Reference website ... see also overview of Williams Syndrome.
approx 1 in 7,500 or 0.01% or 36,266 people in USA [Source statistic for calcuation: "estimated 1 per 7,500 - 20,000 people suffer from Williams syndrome, Genetics Home Reference website" -- see also general information about data sources]
Williams Syndrome: Rare Disease
Williams Syndrome is listed as a "rare disease" by the Office of
Rare Diseases (ORD) of the National Institutes of Health
(NIH). This means that Williams Syndrome, or a subtype of Williams Syndrome,
affects less than 200,000 people in the US population.
About prevalence and incidence statistics:
The term 'prevalence' of Williams Syndrome usually refers to the estimated population
of people who are managing Williams Syndrome at any given time.
The term 'incidence' of Williams Syndrome refers to the annual diagnosis rate,
or the number of new cases of Williams Syndrome diagnosed each year.
Hence, these two statistics types can differ:
a short-lived disease like flu can have high annual incidence but low prevalence,
but a life-long disease like diabetes has a low annual incidence but high prevalence.
For more information see about prevalence and incidence statistics.