By Stan Deresinski, MD, FACP, FIDSA

Clinical Professor of Medicine, Stanford University

Dr. Deresinski reports no financial relationships relevant to this field of study.

SYNOPSIS: Since achieving historic lows, the rates of many sexually transmitted infections has been increasing in the United States. The problem is highlighted by the continued emergence of antibiotic resistance in Neisseria gonorrhoeae.

SOURCE: Centers for Disease Control and Prevention. Sexually Transmitted Disease Surveillance 2018. Available at: Accessed Oct. 9, 2019.

In 2018, the incidence of Chlamydia trachomatis infection, the most common notifiable condition in the United States, increased 2.9% over the previous year to 539.9 cases per 100,000 population. This increase was observed throughout the country, in both males and females, and among all ethnic groups. Adolescents and young adults were disproportionately affected, with two-thirds of cases occurring in individuals 15-24 years of age. In addition, infections were detected much more frequently in females (3,693 cases per 100,000 females) than in males, but this likely is related, at least in part, to the fact that females are targeted for screening. Nonetheless, the incidence of infections in males increased by 38% between 2014 and 2018.

In 2018, gonorrhea was the second most common notifiable condition in the United States with 583,405 cases. (Although Mycoplasma genitalium infections are more common than gonorrhea, it is not a reportable disease.) Since reaching an all-time low in 2009, the reported incidence increased by 82.6%, including a 5.0% increase between 2017 and 2018. The increase has affected both males and females. Antibiotic resistance among Neisseria gonorrhoeae isolates has been increasing, although almost uniform susceptibility to ceftriaxone remains — only 0.2% had an elevated minimal inhibitory concentration (MIC) in 2018.

There has been an almost yearly increase in reported cases of syphilis since the lows observed in 2000 and 2001. The total number of cases reached 115,045 in 2018, 30.4% of which involved primary or secondary syphilis and, therefore, were infectious. The rates of primary and secondary syphilis have increased in women and men. The increase among the latter largely has occurred in men who have sex with men (MSM), with approximately two-fifths of them known to be infected with HIV. At the same time, recent, dramatic increasing incidences in women have raised concern about “a rapidly growing heterosexual epidemic.”

Of additional concern is a rise in cases of congenital syphilis, which reached a rate of 33.1 cases per 100,000 live births in 2018. The number of resultant deaths of newborns increased by 22% to 94.


These results demonstrate that sexually transmitted disease (STD) public health in the United States is going backward, with the number of cases progressively increasing after previously reaching historic lows. Add to that the increasing number of antibiotics to which N. gonorrhoeae has become resistant, and it is obvious that we are facing a critical public health challenge. It is clear that additional resources must be provided to public health agencies to deal with the problem effectively.

In addition, there must be assurance that ready access to healthcare must be made available to all. The Healthy People 2020 Sexually Transmitted Diseases Objectives include reducing the proportion of adolescents and young adults with C. trachomatis infections and reducing gonorrhea rates, as well as reducing the transmission of primary and secondary syphilis and the number of congenital syphilis cases.

Also targeted are young adults with genital HSV-2 infection and the proportion of females (age 15-44 years) who ever have required treatment for pelvic inflammatory disease. In dealing with Chlamydia infection, public health officials aim to increase comprehensive screening for Chlamydia infections in sexually active women with Medicaid or commercial health insurance. This limitation to women with a third-party payer reflects the lack of healthcare accessibility for a significant portion of the U.S. population.