Cases of primary and secondary syphilis (P&S) in the United States increased, in terms of number of cases, by 10.9 percent from 2012 to 2013, according to the Center for Disease Control and Prevention;s (CDC) annual report, Sexually Transmitted Disease Surveillance, 2013, which was published today.


The updated data shows the number of P&S syphilis cases reported to CDC increased from 15,667 in 2012 to 17,535 in 2013. In addition, the rate of syphilis increased from 5.0 to 5.5 cases per 100,000 population (a 10.0% increase) during 2012–2013. This is the highest recorded case count and rate for P&S syphilis since 1995.

Syphilis remains a major health problem, with increased cases occurring among gay, bisexual and other men who have sex with men (MSM). Cases among MSM have been characterized by high rates of HIV co-infection and high-risk sexual behaviors. According to information reported from 49 states and the District of Columbia, 75% of P&S syphilis cases are among MSM.

Concerning geography, the South continued to comprise the largest proportion of cases of P&S syphilis in 2013 (40 percent). In 2013, the 15 states and areas (including the District of Columbia) with the highest rates of P&S syphilis accounted for 70% of all U.S. cases of P&S syphilis.

The state with the highest rate per 100,000 population was Georgia with 10.3 cases per 100,000. The state with the most P&S syphilis cases was California with 3,532, accounting for 20 percent of cases recorded nationally (California was second in rate of syphilis with 9.3 cases per 100,000 population).

Looking at data on race and ethnicity, rates of P&S syphilis remained highest among blacks (16.8 cases per 100,000 population). The rate among blacks was 5.6 times the rate among whites (3.0 cases per 100,000 population).

Primary and secondary syphilis are the earliest stages of infection, reflect symptomatic disease, and are indicators of incident infection.

After decreasing significantly during the 1990s, syphilis in the United States saw it’s lowest rate in 2000 since reporting began in 1941. Since then, the rate increased annually during 2001–2009 before decreasing in 2010 and remaining unchanged during 2011. The rate again increased during 2012 and 2013.

Syphilis is a sexually transmitted disease (STD) that can cause long-term complications if not treated correctly. Symptoms in adults are divided into stages. These stages are primary, secondary, latent, and late syphilis. Syphilis is transmitted via direct contact with a syphilis sore during vaginal, anal, or oral sex. Sores can be found on the penis, vagina, anus, in the rectum, or on the lips and in the mouth. Syphilis can also be spread from an infected mother to her unborn baby.

Other STDs featured in the report included chlamydia and gonorrhea. There were 1,401,906 cases of chlamydia reported in the U.S. in 2013. The rate of chlamydia in the country with 446.6 cases per 100,000 population, a decrease of 1.5 percent.

333,004 cases of gonorrhea were reported last year.Gonorrhea also saw a slight decrease in rate at 0.6 percent.