LATE-ONSET INFECTIONS OF INFANTS IN NEONATAL UNITS

Objective: To examine regional variations in the incidence of late-ons et neonatal infections in Australian and New Zealand neonatal units. M ethodology: A longitudinal, prospective surveillance study of systemic sepsis (septicaemia or meningitis) in 11 neonatal units: 10 in the Au stralian States of the Northern Territory, New South Wales, Queensland , Victoria and Western Australia, and 1 in Christchurch, New Zealand. The results are reported of late-onset neonatal infection (defined as sepsis after 48 h) for the second year of prospective surveillance, da ta being collected from 1 October 1992 to 30 September 1993. Results: Data were available on 24535 live births in Australia, representing ap proximately 10% of all live births in the country. There were 320 epis odes of sepsis in Australian units affecting 294 babies. One hundred o f these episodes (31%) were early-onset; 3.0% of babies admitted to si x tertiary care neonatal units attached to maternity hospitals develop ed late sepsis, and this rate did not differ between units. The propor tion of babies infected was inversely related to birthweight: 22.6% of babies under 1000 g, but 0.6% over 2000 g. Coagulase negative staphyl ococci were the commonest cause of late-onset sepsis. There were 26 ep isodes of S. aureus septicaemia, of which only one was due to MRSA. Me ningitis occurred in 13 babies (5.9%) with late-onset sepsis. The mort ality from late-onset sepsis was 7.7%. Conclusions: Coagulase-negative staphylococci are the commonest cause of late-onset sepsis of babies in neonatal units. There were no major regional differences in the inc idence of, or the organisms causing, late sepsis.