Transmission of cytomegalovirus in fresh and freeze–thawed mother’s own milk to very preterm infants: a cohort study

OBJECTIVES: The objectives of the study were to clarify: (i) the frequency of human cytomegalovirus (HCMV) transmission, (ii) the association between the viral load in mother’s own milk (MOM), the amount of fresh MOM and transmission, and (iii) the frequency of sepsis-like-symptoms (SLS) among infants born to seropositive mothers compared to infants born to seronegative mothers. STUDY DESIGN: This prospective cohort study enrolled very preterm infants (gestational age <32 weeks) from Denmark. Weekly samples of fresh MOM and urine were analyzed for HCMV-DNA. RESULTS: Twenty-six very preterm infants were enrolled. Four acquired an HCMV infection, of which two developed SLS. HCMV-infected infants received MOM with a significant higher viral load compared to the HCMV-uninfected infants. CONCLUSION: A combination of a high viral load and an increased amount of fresh MOM increased the risk of HCMV transmission. SLS was only slightly more common among infants exposed to HCMV positive MOM.