Total Bacterial Colony-forming Units Research Articles

Impact of a Novel Antimicrobial Surface Coating on Health Care–Associated Infections and Environmental Bioburden at 2 Urban Hospitals

Approximately 1 in 25 people admitted to a hospital in the United States will suffer a health care-associated infection (HAI). Environmental contamination of hospital surfaces contributes to HAI transmission. We investigated the impact of an antimicrobial surface coating on HAIs and environmental bioburdens at 2 urban hospitals. A transparent antimicrobial surface coating was applied to patient rooms and common areas in 3 units at each hospital. Longitudinal regression models were used to compare changes in hospital-onset multidrug-resistant organism bloodstream infection (MDRO-BSI) and Clostridium difficile infection (CDI) rates in the 12 months before and after application of the surface coating. Incidence rate ratios (IRRs) were compared for units receiving the surface coating application and for contemporaneous control units. Environmental samples were collected pre- and post-application to identify bacterial colony forming units (CFUs) and the percent of sites positive for select, clinically relevant pathogens. Across both hospitals, there was a 36% decline in pooled HAIs (combined MDRO-BSIs and CDIs) in units receiving the surface coating application (IRR, 0.64; 95% confidence interval [CI], .44-.91), and no decline in the control units (IRR, 1.20; 95% CI, .92-1.55). Following the surface application, the total bacterial CFUs at Hospitals A and B declined by 79% and 75%, respectively; the percentages of environmental samples positive for clinically relevant pathogens also declined significantly for both hospitals. Statistically significant reductions in HAIs and environmental bioburdens occurred in the units receiving the antimicrobial surface coating, suggesting the potential for improved patient outcomes and persistent reductions in environmental contamination. Future studies should assess optimal implementation methods and long-term impacts.

1216. A Novel Antimicrobial Surface Coating Demonstrates Persistent Reduction of both Microbial Burden and Healthcare-Associated Infections at Two High-acuity Hospitals

BackgroundHealthcare-Associated Infections (HAIs) pose substantial risks to patients and hospitals. Surface disinfection practices in hospitals have limited efficacy because surfaces are frequently and easily re-contaminated. A need for innovative technologies to address these challenges exists. One such innovation is a novel antimicrobial surface coating with potential to persistently reduce environmental bacterial load. Here, we use a multicenter, nonrandomized, controlled, pre-post study design to assess the impact of an antimicrobial surface coating on environmental bioburden and HAIs at two high acuity hospitals.MethodsAn antimicrobial surface coating was applied via electrostatic spray to patient rooms and common areas in three selected units at each hospital. Quantitative surface cultures were sent to an independent microbiology laboratory pre- and 11-weeks post-application to identify total bacterial colony-forming units (CFU). HAI outcomes from treatment and contemporaneous control units were assessed using National Healthcare Safety Network protocols for multidrug-resistant organism bloodstream infections (MDRO-BSI) and Clostridium difficile infections (CDI). We used Poisson regression models to compare HAI rates for treated and untreated units for 12-months before and after application of surface coating.ResultsBoth hospitals showed statistically significant decreases in total bacterial CFU following application of the antimicrobial surface coating (64% and 75% decreases in Hospitals A and B, respectively, P < 0.0001). Across both hospitals, there was a 36% decline in pooled HAIs (hospital-onset MDRO-BSI + CDI) following application of surface coating in treated units (IRR = 0.64, 95% CI = 0.44–0.91), and no decline in HAIs over the same period in nontreated units (IRR = 1.20, 95% CI = 0.92–1.55).ConclusionSignificant and persistent reductions in both microbial burden and associated HAIs occurred in units where surfaces were treated with antimicrobial surface coating, suggesting the potential for improved patient outcomes and reduced healthcare costs. Optimal implementation methods and long-term impact should be assessed with further study of this novel environmental control intervention.Disclosures All authors: No reported disclosures.

Microbial community of Pacific abalone (Haliotis discus hannai) juveniles during a disease outbreak in South China

A mass mortality of farmed juvenile abalones (Haliotis discus hannai) occurred in South China in December of 2012. Combined traditional culturing with terminal restriction fragment length polymorphism (T-RFLP) methods, microbial communities associated with juvenile abalones were investigated under different survival conditions, including healthy (HA) and moribund (HM) abalones in the healthy pond with low mortalities, and healthy (DA) and moribund (DM) abalones in the diseased pond with a high mortality rate. The results indicated that both HA and DM exhibited greater microbial diversity and evenness. Moreover, the number of bacterial colony forming units (CFUs) from HA and DM were higher than other samples from the same pond. HA and DA samples harboured absolutely dominant T-RFs with 504 bp (76.2% of total T-RFs) and 436 bp (63.2%) respectively. Nesterenkonia sandarakina, Staphylococcus haemolyticus and Agarivorans albus were the dominate isolates in HA samples, but no Vibrio genus was isolated even on vibrio-specific medium. Reversely, in the DM samples, up to 94% of the total bacterial CFUs were composed of the family Vibrionaceae, represented by Photobacterium swingsii (44%) and Vibrio shilonii (45%). Also, Vibrio was the only cultivated genus from the HM group. Of these Vibrio species, V. atlanticus were detected in HM, DA and DM samples and could generate the T-RF 504 bp. The microbial composition and diversity of juvenile abalones in different surviving states provided insights into the stability and dynamics of microbial communities during disease outbreak which could be helpful to predict and to control disease in the future.

Glove Changing When Handling Money: Observational and Microbiological Analysis

The purpose of this study was to determine the rate of glove changing by mobile food vendors after monetary transactions, and the presence of bacterial contamination on a sample of dollar bills obtained from 25 food vendors near five hospitals in Manhattan, New York City. During 495 monetary transactions observed there were only seven glove changes performed by the workers. Eleven of 34 food workers wore no gloves at all while handling money and food. Nineteen of 25 one-dollar bills collected (76 %) had 400 to 42,000 total bacterial colony-forming units. Colonies were of varied morphology and size. Of these 19 samples, 13 were selected (based on level of growth), and tested for the presence of coliform bacteria, which was found in 10 of the 13 samples. Effective strategies to monitor and increase glove wearing and changing habits of mobile food vendors are needed to reduce risk of foodborne illness.

The effects of age, environmental temperature and relative humidity on the bacterial flora of the upper respiratory tract in calves

The effects of age, environmental temperature and relative humidity on the bacterial flora of the nose and trachea of calves were investigated by sequential sampling of three groups each of eight Friesian-Holstein male calves kept in three different environmental conditions. All calves were vaccinated with a live attenuated vaccine against infectious bovine rhinotracheitis (IBR) when they were 12 weeks old. Nasal and tracheal swabs were collected at 14-day intervals for bacteriological examinations. The upper respiratory tract of calves started to be colonized by various species of bacteria within the first day of life. Although they were born at different periods of the year, the calves in all three groups had similar bacterial loads in their noses and tracheas when they were 1 day old (P greater than 0.05). The total bacterial colony forming units (BCFU) were highly variable from calf to calf and from one time of sampling to another. Despite these variations, there were age-related increases in the total BCFU in nasal and tracheal swabs in all experiments. These increases were influenced by environmental temperature. Vaccination of the calves with a live IBR vaccine appeared to enhance the bacterial colonization of the upper respiratory tract.