While there is good epidemiological evidence for foods as vehicles for norovirus transmission, the precise means of spread and its control remain unknown. The feline calicivirus was used as a surrogate for noroviruses to study infectious virus transfer between hands and selected types of foods and environmental surfaces. Assessment of the potential of selected topicals in interrupting such virus transfer was also made. Ten microliters of inoculum of feline calicivirus deposited onto each fingerpad of adult subjects was allowed to air dry and the contaminated area on individual fingerpads was pressed (10 s at a pressure of 0.2 to 0.4 kg/cm2) onto 1-cm-diameter disks of ham, lettuce, or brushed stainless steel. The virus remaining on the donor and that transferred to the recipient surfaces was eluted and plaque assayed. Virus transfer to clean hands from experimentally contaminated disks of ham, lettuce, and stainless steel was also tested. Nearly 46 +/- 20.3, 18 +/- 5.7, and 13 +/- 3.6% of infectious virus was transferred from contaminated fingerpads to ham, lettuce, and metal disks, respectively. In contrast, approximately 6 +/- 1.8, 14 +/- 3.5, and 7 +/- 1.9% virus transfer occurred, respectively, from ham, lettuce, and metal disks to hands. One-way analysis of variance test showed that pretreatment (washing) of the fingerpads either with water or with both topical agent and water significantly (P < 0.05) reduced virus transfer to < or = 0.9%, as compared with < or = 2.3 and < or = 3.4% transfer following treatments with either 75% (vol/vol) ethanol or a commercial hand gel containing 62% ethanol, respectively. Despite wide variations in virus transfer among the targeted items used, intervention agents tested reduced virus transfer significantly (P < 0.05) when compared with that without such treatments (71 +/- 8.9%). These findings should help in a better assessment of the potential for cross-contamination of foods during handling and also assist in developing more effective approaches to foodborne spread of norovirus infections.
Matched MeSH terms: Disinfection/methods; Hand Disinfection
Glove wearing during patient treatment has been central to dental surgery infection control for over 15 years. However, little is known about the cutaneous effects of glove wearing on the hands of dental healthcare workers (DHCWs). The objective of this project was to assess the hand skin health of DHCWs before and after wearing gloves of two types and to compare this with a control group of non-DHCWs.
Hepatitis A virus (HAV) is an important pathogen which has been responsible for many food-borne outbreaks. HAV-excreting food handlers, especially those with poor hygienic practices, can contaminate the foods which they handle. Consumption of such foods without further processing has been known to result in cases of infectious hepatitis. Since quantitative data on virus transfer during contact of hands with foods is not available, we investigated the transfer of HAV from artificially contaminated fingerpads of adult volunteers to pieces of fresh lettuce. Touching the lettuce with artificially contaminated fingerpads for 10 s at a pressure of 0.2 to 0.4 kg/cm(2) resulted in transfer of 9.2% +/- 0.9% of the infectious virus. The pretreatments tested to interrupt virus transfer from contaminated fingerpads included (i) hard-water rinsing and towel drying, (ii) application of a domestic or commercial topical agent followed by water rinsing and towel drying, and (iii) exposure to a hand gel containing 62% ethanol or 75% liquid ethanol without water rinsing or towel drying. When the fingerpads were treated with the topical agents or alcohol before the lettuce was touched, the amount of infectious virus transferred to lettuce was reduced from 9.2% to between 0.3 and 0.6% (depending on the topical agent used), which was a reduction in virus transfer of up to 30-fold. Surprisingly, no virus transfer to lettuce was detected when the fingerpads were rinsed with water alone before the lettuce was touched. However, additional experiments with water rinsing in which smaller volumes of water were used (1 ml instead of 15 ml) showed that the rate of virus transfer to lettuce was 0.3% +/- 0.1%. The variability in virus transfer rates following water rinsing may indicate that the volume of water at least in part influences virus removal from the fingerpads differently, a possibility which should be investigated further. This study provided novel information concerning the rate of virus transfer to foods and a model for investigating the transfer of viral and other food-borne pathogens from contaminated hands to foods, as well as techniques for interrupting such transfer to improve food safety.
Matched MeSH terms: Disinfection/methods; Hand Disinfection
The aim of this paper was to study hand washing practices in the Neonatal Intensive Care Unit (NICU), Hospital Universiti Sains Malaysia. All medical personnel handling babies in the NICU were observed without their knowledge for a total of three times before and after an educational intervention between November 1, 1993 and December 31, 1993. Hand washing techniques with both Hibisol Spray and Chlorhexidine were scored from 1-4. The results of the study are shown as follows: the number of personnel observed were: before educational intervention -paediatric doctors (PD) 14, non-paediatric doctors (ND) 13 and nurses (N) 48; after educational intervention - PD 10 , ND 12 and N 42. PD and N washed hands significantly more often than ND (p < 0.001), before and after intervention. PD but not ND or N improved their rate of hand washing after educational intervention PD (p= 0.02). The Hibisol handwashing technique was poor in all groups (77.1% of all observations). The Chlorhexidine hand washing technique was better than Hibisol (p<0.0001). However only 15% of observed washes with Chlorhexidine were well done and almost one third were done poorly. Both Hibisol and Chlorhexidine techniques did not improve after educational intervention. Hand washing was performed more often in the Level III than Level II nursery [85% of all observations in Level III and 73% of all observations in Level II, p=0.002]. In conclusion, the present educational program is not sufficient and more direct means should be taken to improve the frequency of hand washing among all medical personnel. All medical personnel in the NICU should be educated in the use of the Hibisol, otherwise Hibisol should be removed from the nursery.
Keywords: Handwashing, doctors, neonatal intensive care unit, nurses
Study site: Hospital Universiti Sains Malaysia, Kelantan, Malaysia
A questionnaire survey on cross-infection control was conducted among 1371 professionally trained dentists whose names appeared in the Malaysian Government Gazette of 1990. A 73.1 percent response rate was obtained. About 13 percent of the dentists routinely did not wear gloves during treatment of patients as opposed to 54 percent who routinely did. About 83 percent and 52 percent of dentists wore a mask and eyewear or glasses respectively when carrying out dental procedures. About 93 percent of dentists would use a new sterile needle for each patient and about 40 percent would wipe working surfaces with disinfectant after each patient. The practice of sterilizing handpieces was found to be uncommon as opposed to the sterilization of hand instruments. Variations were observed in some of the infection control measures by gender, seniority in service and employment status. More than one-third of the respondents had experienced puncture wounds during the last month prior to the survey.
Matched MeSH terms: Disinfection/methods; Disinfection/statistics & numerical data
Awareness of the disinfection and sterilization policy among hospital staff and their knowledge in basic principles and methods of disinfection and sterilization were studied before and after intervention using a self-administered questionnaire. Survey results showed that awareness (56.2%) before intervention was unsatisfactory. The nurses were more aware of the policy than other groups of medical personnel. Those unaware of the policy perform duties from memory or verbal instructions. A significant increase in awareness to 73.3% was observed after intervention (p < 0.05). Knowledge on methods of decontamination, disinfection and sterilization of equipment varies widely from 28.8% to 90.1%. 23.1% were unaware of the temperature used for sterilization while 72.4% did not know how containers of disinfectant should be refill. Only 14.7% knew the recommended method for washing containers. With education improvement was observed. The average knowledge improved from 44.4% to 57.3%. Our results indicated that continuous in-service education is needed to improve, supplement and update knowledge in this field after basic training. In addition orientation programs for new staff should also be aimed at creating awareness and providing information on guidelines and policies related to their duties.
A closed enteral delivery system consisting of a cardboard tetrapack containing the sterile ready-to-use liquid feed and an independent sterile administration set, has been devised. We found bacterial contamination within 24 hours in this system in patients on ventilatory support in intensive care. This emphasises the need for meticulous care in handling enteral feeding systems to prevent environmental contamination.
The present study was conducted to evaluate the role of ingestion through hand and mouth contamination in the absorption of lead in 25 lead-acid battery workers. Levels of personal exposure to airborne lead ranged from 0.004 to 2.58 mg/m3 [geometric mean 0.098, with 25% of samples exceeding threshold limit values (ACGIH) of 0.15 mg/m3]; the mean (SD) blood lead level was 48.9 (10.8) micrograms/dl. Mean hand lead contents increased 33-fold from preshift levels on Monday mornings (33.5 micrograms/500 ml) to midshift levels on Thursday afternoons (1121 micrograms/500 ml). Mouth lead contents increased 16-fold from 0.021 micrograms/50 ml on Mondays to 0.345 micrograms/50 ml on Thursdays. The typical Malay racial habit of feeding with bare hands and fingers without utensils (closely associated with mouth and hand lead levels on Mondays) explained the bulk of the variance in blood lead levels (40%), with mouth lead on Thursdays (closely associated with poor personal hygiene) explaining a further 10%. Air lead was not a significant explanatory variable. The implementation of a programme of reinforcing hand-washing and mouth-rinsing practices resulted in a reduction of the blood lead level by 11.5% 6 months later. These results indicate that parenteral intake from hand and mouth contamination is an important cause of lead absorption in lead-exposed workers.
The plasma cholinesterase baseline levels in Malaysian workers are within the guidelines used. There is a need to carry out close monitoring of workers handling organophosphate s even in a well-run, modern factory where there are no hazards in the plant operation. Abnormal results are mainly because many of our workers are unaware of the health hazards and do not follow orders properly, ie personal hygiene, such as washing of hands before eating, etc. The use of temporary workers should be discouraged because of poor compliance with rules and difficulty in follow up. Product stewardship and education of farmers, sprayers and end users are of paramount importance. Finally there is a great need for educaiton of everyone from factory workers, farmers, sprayers to the general public.