Epidemiological Aspects of Neonatal Necrotizing Enterocolitis

Abstract

Detailed attempts to isolate pathogens were made during an apparent epidemic outbreak of neonatal necrotizing enterocolitis (NEC). In addition, all cases of infants with this disease since 1964 were reviewed for comparison with the present outbreak. Efforts were made to determine a transmissible cause. No bacteria, virus, or fungus common to the infants involved in the outbreak was isolated. Neither could any other

Seasonal variation in the incidence of necrotizing enterocolitis

“…While older data had found temporal and geographic clustering of NEC cases over a 5-year interval in the 1970s, this was coincident with acute gastrointestinal illness in NICU personnel and resolved with increased infection-control measures [15]. Similarly, one report documented a significantly lower incidence of NEC during a 2-month interval in which gowns were worn over street clothes by staff and visitors to the NICU [16]. Infection control measures are an unlikely explanation for what is seen in this contemporary data set given the strict infection control regulations enforced in most nurseries.…”

Epidemiology of Necrotizing Enterocolitis

“…10 The first outbreak in the United States was reported in 1974 and included five cases of NEC that occurred during a 3-week period in a nursery that had only 16 other cases in the previous eight years. 71 Many outbreaks of NEC have been identified, studied, and reported since these early epidemics. They have occurred throughout the United States and in all seasons of the year.…”

Focal Bacterial Infections

“…NEC with necrosis of the bowel wall is a severe, often fatal disease that has been occurring with increasing frequency in recent years. The average annual NEC mortality rate is 13.1 per 100,000 live births; black infants, particularly boys, are three times more likely to die of NEC than white infants, and mortality rates are highest in the southern United States [280,[282][283][284][285][286][287][288][289][290][291]. NEC occurs in about 5% of infants admitted to NICUs; however, the incidence varies widely among centers and from year to year at the same institution [292][293][294][295][296][297][298][299][300][301][302][303][304][305].…”

“…The likelihood of bacteremia accompanying NEC depends on the severity of bowel involvement; the reported incidence has ranged from 10% to 67% among symptomatic infants. Combined data from several large studies showed positive blood cultures in about one third of newborns with NEC [287,288,339,393] species, whereas enterococci and anaerobic bacteria were isolated occasionally. A spectrum of organisms similar to those causing sepsis have been isolated from the peritoneal fluid [287,295,316,340,393].…”