Primary and secondary syphilis--United States, 1997.

Syphilis is an acute and chronic sexually transmitted disease (STD) caused by infection with Treponema pallidum. The disease is characterized by skin and mucous membrane lesions in the acute phase (primary and secondary [P&S] syphilis) and lesions of the bone, viscera, and cardiovascular and neurologic systems in the chronic phase. Because syphilis enhances transmission of human immunodeficiency virus (HIV), prevention of syphilis is important for controlling HIV. During 1986-1990, an epidemic of syphilis occurred throughout the United States. Syphilis rates began to decline in 1991 and have declined each year since that time. To determine whether this decline is reflected in changes in the epidemiology of syphilis, CDC analyzed notifiable disease surveillance data for 1997. This report summarizes the findings of the analysis, which indicate that 8551 cases of primary and secondary (P&S) syphilis were reported in 1997, an 83% decline in cases from the peak of the epidemic in 1990, and that syphilis remains substantially more common in non-Hispanic blacks than in other racial/ethnic groups and continues to be concentrated in the Southern region of the United States [corrected].