8746
Belief in the medicinal use of bed bugs persisted until at least the 18th century , when Guettard recommended their use in the treatment of hysteria .
 person: Guettard
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 person: Guettard