Outbreaks of influenza A virus infection in neonatal intensive care units.
BACKGROUND
Outbreaks of nosocomial influenza virus infections have been described rarely during childhood and even less so in the neonatal period.


METHODS
We report 30 neonates admitted to 2 neonatal intensive care units with nosocomial influenza A virus infection, which occurred in 2 outbreaks during 1999. Risk factors for infection were evaluated, and control measures were adopted. Virus was detected by indirect immunofluorescence antibody screen. Any infant with nasopharyngeal aspirate positive for influenza A virus was considered infected.


RESULTS
Of 95 infants screened 30 were positive for influenza A virus (31.5%). Mean birth weight was 1622 g, and mean gestational age was 31 weeks in the infected group. In the noninfected group mean birth weight was 2594 g and mean gestational age was 36.4 weeks. Low birth weight, short gestational age, twin pregnancy and mechanical ventilation were identified as risk factors for infection. Clinical symptoms were seen in 22, and 8 were asymptomatic. Clinical features were predominantly respiratory and digestive. The outcome was favorable in all cases.


CONCLUSIONS
Infection by influenza virus has to be considered as a possible cause of nosocomial infection in the neonatal period. Control measures and prevention are important.
Sagrera
Xavier
X
Servei de Neonatologia-Pediatra, SCIAS Hospital de Barcelona, Spain.
Ginovart
Gemma
G
Raspall
Frederic
F
Rabella
Nuria
N
Sala
Pere
P
Sierra
Montserrat
M
Demestre
Xavier
X
Vila
Clara
C
D001724:Birth Weight; D003428:Cross Infection / Q000453:epidemiology / Q000503:physiopathology / Q000517:prevention & control / Q000821:virology; D004196:Disease Outbreaks; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000453:epidemiology* / Q000503:physiopathology / Q000517:prevention & control / Q000821:virology*; D009980:Influenza A virus / Q000302:isolation & purification*; D007251:Influenza, Human / Q000453:epidemiology* / Q000503:physiopathology / Q000517:prevention & control / Q000821:virology*; D007363:Intensive Care Units, Neonatal; D008297:Male; D011247:Pregnancy; D012121:Respiration, Artificial; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D014427:Twins