Cytomegalovirus Saliva Shedding Kinetics in Children with Congenital CMV Infection

Congenital CMV (cCMV) is a common congenital viral infection worldwide and the most common cause of childhood non-genetic sensorineural hearing loss (SNHL). The kinetics of CMV detection (shedding) from mucosal surfaces have not been extensively described in children with cCMV due to a lack of systematic newborn CMV screening and follow-up protocols. The aim of this study is to describe the natural history of saliva CMV shedding in a cCMV cohort, which was identified through universal newborn screening.

As part of the CMV and Hearing Multicenter Screening study (CHIMES), 100 332 newborns were screened, and those confirmed to have cCMV were followed prospectively every six months for four years to determine hearing outcomes. Saliva CMV DNA shedding kinetics, including duration, viral load (VL), and intermittent shedding are described and compared between groups with and without newborn symptoms and hearing loss in children with ≥5 visits.

The 197 children with confirmed cCMV shed CMV DNA in saliva for a median of 20 months with CMV shedding frequency decreasing from 100% at cCMV confirmation to 9.5% four years after enrollment. Similarly, median CMV DNA VL levels decreased from 8.89 × 106 IU/mL at the confirmation visit to 1.64 × 103 IU/mL at the 4-year follow-up visit. Saliva CMV shedding duration was similar between children with or without newborn symptoms (median 20 months for both groups; P = .57) or between those with SNHL vs normal hearing (P = .8). A third of the cohort intermittently shed CMV DNA in saliva (64/197, 32.5%).

In this large cohort of children with cCMV identified by universal CMV newborn screening, CMV DNA was detectable in saliva for a median of 20 months, irrespective of newborn symptoms or hearing outcomes. Intermittent shedding was noted in a third of the cohort.