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More than 50% of American adults have oral herpes, which is commonly known as "cold sores" or "fever blisters." The herpes virus can be active on the skin surface without showing any signs or causing any symptoms.
Vampire bats have a natural anticoagulant in their saliva that permits continuous bleeding after they painlessly open a wound with their incisors. This capillary blood does not cause any significant blood loss to their victims.
Though Candida and Aspergillus species are the most common fungal pathogens causing invasive fungal disease in the immunocompromised, infections due to previously uncommon hyaline and dematiaceous filamentous fungi are occurring more often today. Rare fungal infections, once accurately diagnosed, may require surgical debridement, immunotherapy, and newer antifungals used singly or in combination with older antifungals, on a case-by-case basis.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.
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