Outbreak Corner (1998 Weeks 13-34)

Outbreak Corner

During this reporting period, CAREC provided field assistance for the investigation of the following outbreak:

Gram Negative Nosocomial Infections: Dominica

An investigation into a nosocomial outbreak of gram-negative infections at the neonatal unit of the Princess Margaret Hospital in May 1998, revealed that 31 babies had been affected between January and May, 1998. Serratia and Klebsiella were the most frequently isolated bacterial pathogens and a review of the antibiograms on 30 of these cases indicated that 83.0 percent of them were resistant to ampicillin. Attack rates by month of birth as well as by month of admission to the neonatal unit were highest during the month of April. The distribution of cases by week of birth revealed that 70.0 percent of them had been born during the fourth week of one month and the first week of the next. Analysis of the data indicated that transmission of infection had occurred both in the delivery area as well as in the neonatal unit.

It was concluded that a combination of factors rather than any single exposure could have contributed to this increase in gram-negative infections. Some of these may have included:

	The non wearing of masks during delivery and other procedures;
	Loss of potency of the Cidex solution near the end of the month resulting in inadequate disinfection of instruments [Cidex solutions were being changed around the beginning of every month];
	Cross-contamination from gloves and instruments immersed in the Cidex solution to surfaces and instruments in the delivery and neonatal units;
	Warm ambient temperatures overnight [the central air-conditioning unit for the delivery unit is turned off at nights] would support the multiplication and growth of organisms in the solutions and on contaminated surfaces; and
	Improper cleaning and storage of the resuscitation equipment.

The importance of maintaining active surveillance for nosocomial infections cannot be overemphasised. The economic impact of these infections is quite substantial to the patient, the hospital and the society as a whole.