CAUTION: Loose Women Ahead

This is a great story about a retrospective of 20th-century health posters from the permanent collection of the National Library of Medicine. Many of them were created by the Public Health Service during World War II to warn the troops about the dangers of casual sex. Titled “An Iconography of Contagion,” the exhibition features work from numerous countries on an array of diseases, among them syphilis, malaria, tuberculosis and AIDS. The posters are on display at the National Academy of Sciences in Washington through Dec. 19.