Minnesota's First Year Screening Every Newborn for Congenital CMV

Congenital cytomegalovirus (cCMV) is the most common infectious cause of birth defects in the United States and the most common non-genetic cause of permanent hearing loss in children. It affects about 0.5% of U.S. births, but only about 10% of infected babies show signs at birth — so most are never identified. In February 2023, Minnesota became the first state to screen every newborn for it.

How the screening works

Unless parents opt out, every baby born in Minnesota is tested for CMV with a PCR test on the dried blood spot collected for newborn screening, run at the Minnesota Department of Health. (An earlier Minnesota study found dried blood spots detect about 75% of infections on average.)

1. Screen positive: the baby should have a diagnostic PCR test on urine within the first 21 days of life.
2. Diagnosed: recommended follow-up includes a complete blood count, liver tests, brain imaging, and hearing and eye exams.
3. Followed: the health department tracks every baby with cCMV to make sure they get care and to learn about long-term outcomes. Clinicians and labs also report CMV infections found in the first 90 days of life, which helps catch cases screening missed.

Early identification lets doctors use antiviral treatment when appropriate and monitor hearing and development.

The first year

From February 6, 2023, to February 5, 2024:

Of the 176 confirmed cases, 160 had brain imaging, 157 hearing tests and 141 eye exams; 132 (75%) had all three. Fifty-nine (34%) had at least one clinical finding, most often nonspecific imaging abnormalities, though not every finding led to disease. Screening uncovered cCMV-related findings in seven infants that would not otherwise have been apparent.

What it shows

Screening worked: nearly all positive screens were confirmed, and most babies got full evaluations and care. It found infants with brain abnormalities and those with, or at risk of, cCMV-related hearing loss who might have been missed by routine care or targeted testing. Observed prevalence, 0.3% of live births, was lower than the 0.45% estimated in a 2016–2019 Minnesota study. The three missed cases show the need to keep evaluating the screening test's sensitivity; a rule making cCMV a reportable disease was under way. Surveillance alongside screening, plus long-term follow-up, will guide cCMV screening policy elsewhere.

Sources

Based on Tory Kaye, Elizabeth M. Dufort, Sondra D. Rosendahl, et al., "Notes from the Field: Universal Newborn Screening and Surveillance for Congenital Cytomegalovirus — Minnesota, 2023–2024," Morbidity and Mortality Weekly Report, volume 73, Centers for Disease Control and Prevention; a work of the United States government in the public domain.