Table 1.

Potential vaccination strategies to reduce the disease burden of cCMV

Target Population	Advantages	Disadvantages
12–18 months (boys and girls)	Age at which universal immunization is most readily achieved. Rapid reduction of cCMV rates, if vaccination prevented infection or shedding in this age group (an important source of maternal infection). Potential for “herd immunity” that could prevent additional exposures, if vaccine reduced transmission to other children.	Potential resistance to adding additional doses to childhood vaccine schedule. Potential ethical issue of immunizing infants/toddlers with vaccine in absence of direct serious disease risk. Would require a vaccine that either prevents infection or eliminates CMV shedding if infection occurs. Would not have an effect on sexual transmission unless protection persists for 15 or more years. Vaccine effect in seropositives vs. seronegatives may be different; If required, serological screening may complicate vaccine delivery. Would not address CMV infections and transmissions from children who acquire CMV infection during birth or through breast milk.
Adolescent girls	Immunization of target population prior to pregnancy.	Might require longer vaccine duration of effect than toddler vaccine to lead to benefit, or may require a booster dose later in life Challenges in achieving high vaccination coverage for adolescent vaccines. Vaccine effect in seropositives vs. seronegatives may be different. If required, serological screening may complicate vaccine delivery.
Women before pregnancy	Population with most direct likely impact on cCMV.	Same as adolescent girls, May be difficult to identify at-risk women and vaccinate before pregnancy (though catch-up immunizations could be offered to women after delivery).