1 Although any individual may develop a case of pinworms, the infection occurs most frequently in school children between 5 to 10 years of age.  Pinworm infections occur in all socioeconomic groups; however, human-to-human spread is favored by close, crowded living conditions. Spread among family members is common.
Before they start collecting, stamp collectors try to identify the types of stamps. These will help them segregate and sort stamps according to their classification. On its basic concept, there are three main classifications of stamps â special, commemorative, and definitive.
What is a Forever Stamp? Forever Stamps are a special type of stamp created by the United States Post Office that will always be worth one First Class stamp. When they were initially created in 2007 a Forever Stamp cost only $0.41. Their value has increased since then and they are now worth significantly more.