4126.0: Tuesday, October 23, 2001 - 1:45 PM

Abstract #21497

Using DNA markers to model pathogen spread in child care centers

Louise Lawson, PhD1, Xi Jiang, PhD2, Janelle Mills, BS2, Amy McCraw, MSW1, and Larry K. Pickering, MD3. (1) Children's Hospital of The King's Daughters, Center for Pediatric Research, 855 West Brambleton Ave, Norfolk, VA 23510, 757-668-7340, lawsonml@chkd.com, (2) Eastern Virginia Medical School, Center for Pediatric Research, 855 W. Brambleton Ave., Norfolk, VA 23510, (3) Center for Pediatric Research, E.Virginia Medical School & Children's Hosp. of The King's Dghtrs, 855 W. Brambleton Ave, Norfolk, VA 23510

Background: We developed a group of PCR-detectable non-infectious DNA markers that can be used to model transmission of pathogens. The markers are removed by soap and water hand washing, inactivated by chlorine bleach, stable on surfaces for up to 30 days and spread in the environment in the same manner as infectious particles. A study was conducted in two child care centers (CCCs) to compare the rate of DNA marker spread in classrooms with different hygiene practices. Methods: The marker was placed on the handle of a toy given to toddlers. Environmental surfaces and hands were swabbed after 6 hours. An observer recorded hygiene-related activities and made a subjective rating of overall cleanliness. Results: Observed hygiene practices were strikingly different between the two centers. Center 1 practices were superior on all measures (e.g. hand washing practices, surface cleaning, shared washrags). However, spread of the marker following introduction on the toy was significantly lower in Center 2, with only 10% of swabs positive (vs. 66% in Center 1, p < .01). This discrepancy was apparently due to removal of the toy after ½ hour in Center 2 (vs. 2.75 hours in Center 1). Conclusions: Removal and cleaning of toys on a regular basis during the day may have a substantial impact on infection rates in CCCs. DNA markers can be used to identify which hygiene practices have the most impact without waiting for illness to occur. This will result in more manageable hygiene policies, increased compliance, and decreased illness.

Learning Objectives: At the conclusion of the session, the participant (learner) in this session will be able to: 1. Describe how DNA markers can be used to model pathogen transmission; 2. Discuss the utility of using DNA markers to study the impact of hygiene interventions in institutional settings; 3. List and prioritize the effectiveness of several hygiene activities in child care.

Keywords: Methodology, Child Care

Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.

The 129th Annual Meeting of APHA