Incidence, Risk Factors, and Morbidity of Acquired Postnatal Cytomegalovirus Infection Among Preterm Infants Fed Maternal Milk in a Highly Seropositive Population.

BACKGROUND: In preterm infants cytomegalovirus (CMV) infection acquired through maternal milk has been related to morbidity. However, infants who may receive higher titers of protective antibodies from highly seropositive mothers have not been studied in detail. METHODS: A cohort of 188 ≤30-week-old infants was monitored from admission to discharge. CMV-DNA, hematology, liver enzymes, neutralizing antibodies, and CMV-DNA-lactia were tested periodically. RESULTS: Mothers of 157 infants (83.5%) were CMV-seropositive. A total of 24/157 (15.3%) infants became infected (95% confidence interval [CI], 9.8-22.6), particularly those of lower gestational age (GA; relative risk [RR], 2.32; 95% CI, 1.01-5.34 for 23-26 weeks). Low (<1:64) neutralizing antibody titers were similarly detected in CMV-infected and uninfected infants. Mean DNA-lactia in mothers was higher in CMV-infected than in uninfected infants (5.34 log vs 4.60 log). Clinical findings suggestive of CMV disease were similar in CMV-infected (50.0%) and CMV-uninfected (51.1%) infants. Although transitory, >2 laboratory test abnormalities occurred more frequently among CMV-infected (39.1%) than CMV-uninfected (2.1%) infants. More severe stages of retinopathy of prematurity (ROP) were found among CMV-infected infants (adjusted RR, 2.51; 95% CI, 1.07-5.91). Although deaths were more frequent among infected infants, none of the deaths could be directly attributed to CMV. CONCLUSIONS: Postnatal CMV infection acquired by exposure to raw maternal milk is very frequent among extremely premature newborns, being facilitated by high DNA-lactia and lower GA, regardless of maternally acquired neutralizing antibody levels. The association with advanced stages of ROP is a concern and needs to be further explored in larger studies.

Diphtheria, tetanus, and varicella immunity in health care workers in neonatal units.

BACKGROUND: Susceptible health care workers are at risk of acquiring and transmitting vaccine-preventable diseases to or from patients. The objective of this study was to assess antibody levels against diphtheria, tetanus, and varicella in healthcare workers. METHODS: Antibody levels against diphtheria, tetanus, and varicella were measured in health care professionals in 2 neonatal units at the Federal University of São Paulo, Brazil. RESULTS: Between September and November 2002, 215 of 222 (96.8%) health care workers were studied. Of those, 122 (56.7%) gave oral information regarding their vaccination status against diphtheria and tetanus and only 9 (4.2%) had their vaccination cards. Geometric mean antibody levels against diphtheria, tetanus, and varicella were 0.89 IU/mL (95%CI, 0.73 to 1.08), 0.86 IU/mL (95%CI, 0.68 to 1.07) and 1.10 IU/mL (95%CI, 0.98 to 1.24), respectively. Using internationally accepted definitions, 200 (93.0%) and 182 (84.7%) individuals had full protection against diphtheria and tetanus, respectively. Regarding varicella, 213 (99.1%) individuals were immune and 2 (0.9%) had equivocal immunity against varicella. Of 65 (30.2%) individuals without previous history of the illness, 63 (96.9%) were immune against varicella zoster virus. CONCLUSIONS: Based on serologic screening, most professionals were immune to diphtheria, tetanus, and varicella. Absence of previous history of varicella was an unreliable identifier of susceptibility to varicella zoster virus in the health care workers studied.