Increase in Incidence of Congenital Syphilis — United States, 2012–2014

Virginia Bowen, PhD; John Su, MD, PhD; Elizabeth Torrone, PhD; Sarah Kidd, MD; Hillard Weinstock, MD


Morbidity and Mortality Weekly Report. 2015;64(44):1241-1245. 

In This Article

Disease Trends

The number of CS cases declined in the United States during 2008–2012 from 446 to 334 cases (10.5 to 8.4 cases per 100,000 live births), reflecting trends in rates of P&S syphilis among women, which decreased from 1.5 to 0.9 cases per 100,000 women (Figure). During this period, all regions of the United States experienced a decrease in CS rates except the Midwest, where the rate increased 62% (from 4.2 to 6.8 cases per 100,000 live births) (Table 1). The increase in CS in the Midwest was attributed primarily to increases in CS rates in Illinois and Ohio, which occurred 1–2 years after observed increases in P&S syphilis among women in these states.[6] Substantial declines occurred in all other regions (51% in the Northeast, 46% in the West, and 16% in the South), leading to an overall national decline in CS rates to the lowest level since 2005.


Congenital syphilis (CS) rate* among infants aged <1 year and rate of primary and secondary (P&S) syphilis among women — United States, 2008–2014§
*CS rates during 2008–2013 were calculated by using annual live birth data as denominators. Available at
P&S syphilis rates during 2008–2013 were calculated by using bridged race U.S. Census population estimates as denominators. Available at
§The CS rate and P&S syphilis rate for 2014 were calculated by using 2014 case counts and 2013 denominators.

Racial disparities in CS rates between non-Hispanic blacks (blacks) and non-Hispanic whites (whites) increased during 2008–2012, because relative decreases in rates of CS were greater among whites (21%) than blacks (11%). As has been observed previously, the majority of CS cases (57%) in 2012 continued to be among infants whose mothers were black.[2]

During 2012–2014, the number of reported CS cases in the United States increased from 334 to 458, representing an increase in rate from 8.4 to 11.6 cases per 100,000 live births. As has been observed with earlier CS trends,[2] the increase in CS rates during 2012–2014 reflected an increase in the rate of P&S syphilis among women (22.2% increase, from 0.9 to 1.1 cases per 100,000 women) during the same period (Figure). Increases in CS rates occurred in all regions but were greatest in the West, where the rate more than doubled (from 5.5 to 12.8 cases per 100,000 live births) (Table 1). In total, 19 states reported an increase in number of CS cases and CS rates during 2012–2014, including California (from 35 to 99 cases; 6.9 to 20.0 cases per 100,000 live births), Florida (from 37 to 47 cases; 17.4 to 21.8 per 100,000 live births), Louisiana (from 33 to 46 cases; 52.7 to 72.8 per 100,000 live births), Michigan (from 7 to 15 cases; 6.2 to 13.2 per 100,000 live births), and New York (from 8 to 22 cases; 3.3 to 9.3 per 100,000 live births). Although there was an overall national increase, the number of CS cases and CS rates decreased in multiple large states, including Texas (from 78 to 74 cases; 20.4 to 19.1 per 100,000 live births) and Ohio (from 19 to 15 cases; 13.7 to 10.8 per 100,000 live births).

All racial/ethnic groups experienced an increase in case counts and rates of CS during 2012–2014 (Table 1). The CS rate among whites, blacks, and Hispanics increased 61%, 19%, and 39%, respectively. In 2014, the rate among blacks remained approximately 10 times the rate among whites and three times the rate among Hispanics.

Northeast: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont; Midwest: Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin; South: Alabama, Arkansas, Delaware, District of Columbia, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, and West Virginia; West: Alaska, Arizona, California, Colorado, Hawaii, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming.