Missed Chances to Prevent Congenital Syphilis in Clark County, Nevada, 2017–2022

At a glance

• Known before: U.S. syphilis cases roughly tripled in 2018–2022. Congenital syphilis — passed from mother to baby — can cause severe illness and death in infants, but it is preventable by screening and treating pregnant females.
• Found here: in Clark County, Nevada, in 2017–2022, only about half of the mothers whose infants had congenital syphilis got prenatal care. About half had visited an emergency department (ED) while pregnant, a possible chance for timely testing, and testing was done at 68% of those visits.
• What follows: lack of prenatal care blocked timely testing and treatment. Visits in settings such as EDs could offer timely testing and, linked to prompt treatment, might help prevent congenital syphilis.

The problem

Congenital syphilis can cause stillbirth, miscarriage or newborn death, and blindness, deafness, developmental delay and bone abnormalities in babies who survive. Screening and treating at the right times in pregnancy prevents it. Nationally in 2022, a lack of timely testing and inadequate treatment in pregnancy contributed to 88% of reported cases. That year Nevada ranked eighth in the country for primary and secondary syphilis and for congenital syphilis. Clark County is the state's most populous county.

How it was studied

The Southern Nevada Health District (SNHD) linked its syphilis surveillance data for females aged 15–44 with records of their infants with congenital syphilis, live-born or stillborn, and with ED discharge data from every hospital in the county.

Each mother's case was placed in a cascade of missed chances:

1. no prenatal care;
2. prenatal care begun less than 45 days before delivery;
3. care begun earlier, but syphilis testing less than 45 days before delivery;
4. care and testing in time, but treatment begun less than 30 days before delivery.

Forty-five days allows time to seek care, be tested, get results and start treatment. An ED visit counted as a testing opportunity if the woman was pregnant, it came at least 30 days before delivery, she could have had syphilis then, and she hadn't already been tested.

What was found

Syphilis diagnoses among females of reproductive age, Clark County, 2017–2022. CDC, MMWR.

• Rising cases: syphilis (all stages) among females of reproductive age rose from 43.1 to 143.9 per 100,000.
• Pregnancies: 530 pregnant females were diagnosed, and 195 (36.8%) delivered an infant with congenital syphilis. Of the 335 whose pregnancies did not end in a known case, 85.4% had prenatal care.
• Prenatal care: of the 195 mothers, only 84 (43.1%) had prenatal care — 21 starting in the first trimester, 24 in the second and 28 in the third, with 11 unknown.
• Down the cascade: 49 of the 84 began care at least 45 days before delivery; 35 of them were tested in time; and only 14 of those were treated with a recommended regimen at least 30 days before delivery. Seven of those had test results to judge the response, and all seven looked like reinfection or treatment failure — five had been treated in the first trimester and not retested until delivery.
• No prenatal care: of the 111 mothers without it, 36 (32.4%) were tested before the delivery visit, but most (72.2%) less than 45 days before delivery; none of the 10 tested earlier were treated in time.

The cascade of missed opportunities for prevention. CDC, MMWR.

Emergency departments: 112 of the 195 mothers (57.4%) had at least one ED visit that was a chance to test, and 53 of them had no prenatal care. Across 250 such visits, the medical record noted pregnancy at only 54 (21.6%), and syphilis testing was done at 171 (68.4%); 59 of the 112 women were tested in an ED.

What it means

Since 2021, Nevada law has required syphilis screening at the first prenatal visit, early in the third trimester (28–32 weeks) and at delivery — but not everyone gets prenatal care. Testing in other settings improves timely diagnosis and treatment in pregnancy, and pilot programs have offered routine opt-out screening to patients in EDs who meet set criteria. In Clark County, about one third of the ED chances were missed, and mothers without prenatal care who were tested were mostly tested too late. Offering testing at health care visits, EDs included, and making sure positive results lead to treatment could help.

Limitations

• One county only — though Clark County's data cover all its residents' lab tests, and it had about 78% of the state's primary and secondary syphilis cases in 2021.
• Little data on factors such as transportation or insurance.
• No data on ED test results or on treatment after a positive test.
• Reasons for ED visits weren't known; a clinician may have judged a patient not suited to testing at that visit.

For public health

Improve access to prenatal care. In high-prevalence places like Clark County, opt-out syphilis testing of females of reproductive age at any suitable health visit, including in EDs, may catch pregnant women who can't or won't get prenatal care — and, with systems to ensure prompt treatment after a positive result, prevent congenital syphilis.

Sources

Based on "Missed Opportunities for Congenital Syphilis Prevention — Clark County, Nevada, 2017–2022," by Jessica A. Penney and colleagues of CDC and the Southern Nevada Health District, Morbidity and Mortality Weekly Report, CDC; a work of the United States government in the public domain.