Vibrio vulnificus belongs to the autochthonous bacterial flora of warm estuarine waters. It can cause lifethreatening extraintestinal disease in persons who have underlying illness and who consume raw shellfish or contact wounds with estuarine water. Currently, very little is known about genetic diversity within this species. In this report, we describe high-level variation in restriction fragment length polymorphism profiles among 53 clinical and 78 environmental isolates, as determined by pulsed-field gel electrophoresis. In contrast, ribotype profiles showed greater similarity. When combined ribotype profiles of clinical and environmental isolates were analyzed, four predominant clusters were observed. Interestingly, a low number (16%) of clinical isolates were found in cluster C, compared with clusters A, B, and D (range, 50 to 83%). In addition, 83% of all Hawaiian isolates were located in a single cluster, indicating a possible relationship between geography and genotype. We also report that spontaneous translucent colonial morphotypes were distinct by both restriction fragment length polymorphism and biochemical profiles, compared with opaque parent strains.

Clamped homogeneous electric field gel electrophoresis and a computer program for managing electrophoresis banding patterns (ELBAMAP) were used to analyze genomic DNA of 118 Vibrio vulnificus strains, isolated from three oysters by direct plating. Analysis with SfiI resulted in 60 restriction endonuclease digestion profiles (REDP), while analysis with SrfI produced 53 different REDP. Similarities between REDP ranged from 7 to 93%. Principal-component analysis showed that the strains were heterogeneous. Vibrio vulnificus is an estuarine organism that occurs naturally in temperate and tropical climates. It is commonly found in seawater and sediment and is associated with various marine life forms (10, 16, 18, 19, 24, 26). It is considered one of the most invasive and rapidly lethal human bacterial pathogens known today. Human disease can occur from ingestion of raw seafood, mainly raw oysters (2, 13), or by infection of skin lesions. V. vulnificus poses the greatest risk to persons who are compromised, especially those with liver dysfunctions (2, 13, 23). The fatality rate is greater than 50% for individuals with primary septicemia (15). Because this at-risk population is ever growing, food safety precautions for such opportunistic pathogens are increasingly important. Although much is known of

For many years, sanitarians have specified that the hands of food service workers should be washed and rinsed in warm or hot water to reduce the risk of cross‐contamination and disease transmission. In the food service environment, it has been suggested that handwashing with water at higher temperatures contributes to skin damage when frequent handwashing is necessitated, and that insistence on hot water usage is a deterrent to handwashing compliance. Separate handwashing studies involving different water temperatures and soap types (antibacterial versus non‐antibacterial) were performed. The ‘glove‐juice’ technique was employed for microbial recovery from hands in both studies. Initial work evaluated antimicrobial efficacy based on water temperature during normal handwashing with bland soap. Uninoculated, sterile menstrua (tryptic soy broth or hamburger meat) was used to study the effects of treatment temperatures (4.4°C, 12.8°C, 21.1°C, 35°C or 48.9°C) on the reduction of resident microflora, while Serratia marcescens‐inoculated menstrua was used to evaluate treatment effects on the reduction of transient contamination. Results of this first study indicated that water temperature exhibits no effect on transient or resident bacterial reduction during normal handwashing with bland soap. The follow‐up study examined the efficacy and skin irritation potential involving water temperatures with antimicrobial soaps. Hands of participants were contaminated with Escherichia coli inoculated ground beef, washed at one of two water temperatures (29°C or 43°C) using one of four highly active (USDA E2 equivalency) antibacterial soaps having different active ingredients (PCMX, Iodophor, Quat or Triclosan). Skin condition was recorded visually and with specialized instrumentation before and after repeated washing (12 times daily), measuring total moisture content, transepidermal water loss and erythema. Overall, the four soap products produced similar efficacy results. Although there were slight increases in Log10 reductions, visual skin irritation, loss of skin moisture content and transepidermal water loss at higher temperatures, results were not statistically significant for any parameter.

The SimPlate Total Plate Count (TPC) method, developed by IDEXX Laboratories, Inc., is designed to determine the most probable number of aerobic microorganisms in foods. The 24-h test was compared to the conventional plate count agar (PCA) method, the Petrifilm Aerobic Count plates, and the Redigel Total Count procedure for enumerating microflora in 751 food samples. Results using the SimPlate TPC method were highly correlated (r > or = 0.96) with results from other test methods. Slopes (0.96-0.97) were not significantly different from 1, and y intercepts (-0.03-0.08) were not different from O. The SimPlate has a high counting range (> 1600 most probable number per single dilution), thus requiring fewer dilutions of samples compared to other methods evaluated. Some foods, e.g., raw liver, wheat flour, and nuts, contain enzymes that gave false-positive reactions on SimPlates. Overall, however, the SimPlate TPC method is a suitable alternative to conventional PCA, Petrifilm, and Redigel methods for estimating populations of mesophilic aerobic microorganisms in a wide range of foods.

The efficiency of either handwashing or use of alcoholic instant hand sanitizers (AIHS) has been reported against normal microflora (NF) or transient microflora (TF) using marker bacteria or viruses. Most studies were performed to support use in health care employing techniques that poorly mimic food service. When AIHS is used alone, application quantity, exposure period, alcoholic concentrations and type influence effectiveness. Relevant to the food industry, little work has been done in order to understand the variables affecting efficacy when handwashing and AIHS are combined. Although AIHS has been suggested as a replacement for fingernail brushes in health care, little is known about either application when heavy soil is present. The experiments described examine the effects of sanitizer quantity on efficacy when used after a standard handwash and use of AIHS to disinfect the nail region when contaminated with high levels of organic soil. In these studies, subjects contaminated hands or nail region with TF marker, either Serratia marcescens in Tryptone soya broth or Escherichia coli JM109 in ground beef, respectively. One hand or selected fingers are sampled to establish TF and/or NF baseline counts. For handwashing and AIHS use, hands were washed with a mild antimicrobial soap (AS) (0.5% triclosan), followed by paper towel drying and application of various quantities of AIHS. With fingernail studies, hands and nail regions were washed with tap water, bland soap (BS), AS, AIHS, BS and AIHS or fingernail brush with BS. Using the combined handwash and AIHS to enhance the hygiene process, there were significant (P ≤ 0.05) increases in efficacy as quantity of AIHS increased, a significant difference in efficacy over handwashing alone is seen only when larger quantities (3 mL and 6 mL) of AIHS are employed. In fingernail studies, overall lower levels of E. coli were removed from artificial vs. natural nails and a statistically significantly (P ≤ 0.05) improvement was seen when a fingernail brush was used over all other methods, including BS wash followed by AIHS.