Transmission of cytomegalovirus from mothers to preterm infants by breast milk.
OBJECTIVE
To assess the risk of transmission of cytomegalovirus (CMV) by breast milk from CMV-seropositive mothers to their breast-fed preterm infants and to evaluate their outcome.


METHODS
The study population comprised breast-fed preterm infants with a birth weight of <1,500 g and gestational age of <35 weeks. Venous blood samples from the mothers and infants were tested for CMV IgG and IgM antibodies on the 5th and 30th day after birth. Breast milk was obtained for CMV DNA detection by polymerase chain reaction and viral culture on the 5th day and on the 3rd, 6th and 12th week. Urine samples of the babies were collected at the same time for CMV culture. Neurodevelopmental assessment was done at 6 months of age, corrected for preterm birth.


RESULTS
Thirty-eight mothers and 42 infants (including 4 sets of twins) were enrolled in the study. A mother-infant pair was excluded because of inadequate breast milk collection. Thirty-six mothers (97.3%) were CMV-seropositive. CMV DNA of breast milk was detected in 35 seropositive mothers. Six infants of 5 mothers were infected (infected group) at a mean of 77 days after birth, and 34 infants of 31 mothers were not (noninfected group). In all the mothers of the infected group, CMV virus could be cultured from the milk whey. The average maternal CMV IgG on day 5 after delivery was higher in the infected than in the noninfected group. Sepsis-like symptoms and hyperbilirubinemia were more frequently noted in the infected infants than in the noninfected, but the difference was not statistically significant. Neurodevelopmental outcome did not significantly differ between the 2 groups.


CONCLUSIONS
The risk of CMV infection in breast-fed premature infants was highest when the mothers shed viable virus in their breast milk. These mothers had high CMV IgG, which may help identify those mother-infant pairs at risk. Inactivation of the virus in milk by freezing may be a way of reducing the transmission of this virus via breast milk.
Jim
Wai-Tim
WT
Division of Neonatology, Mackay Memorial Hospital, Taipei, Taiwan. waitim@msl.mmh.org.tw
Shu
Chyong-Hsin
CH
Chiu
Nan-Chang
NC
Kao
Hsin-An
HA
Hung
Han-Yang
HY
Chang
Jui-Hsing
JH
Peng
Chun-Chih
CC
Hsieh
Wen-Shyang
WS
Liu
Kuei-Chen
KC
Huang
Fu-Yuan
FY
D001942:Breast Feeding; D003586:Cytomegalovirus Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000635:transmission*; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007234:Infant, Premature; D018445:Infectious Disease Transmission, Vertical; D008297:Male; D008895:Milk, Human / Q000821:virology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000821:virology*; D011336:Probability; D018570:Risk Assessment; D013624:Taiwan / Q000453:epidemiology
D004279:DNA, Viral