3. HYGIENE PRACTICE: WHERE AND WHEN

Physical interventions to interrupt or reduce the spread of respiratory viruses: systematic review.
Jefferson T., Foxlee R., Del Mar C., et al. British Medical Journal 2007; 27 Nov.
This paper describes a systematic review of evidence for the effectiveness of physical interventions to interrupt or reduce the spread of respiratory viruses. Of 2300 titles scanned 138 full papers were retrieved, including 49 papers of 51 studies. It was concluded that routine long term implementation of some physical measures to interrupt or reduce the spread of respiratory viruses might be difficult but many simple and low cost interventions could be useful in reducing the spread.

Environmental contamination with rhinovirus and transfer to fingers of healthy individuals by daily life activity.
Winther B., McCue K., Ashe K., Rubino J.R., Hendley J.O. Journal of Medical Virology 2007;79:1606-10.
Fifteen adults with rhinovirus colds stayed overnight in a hotel. Ten touched sites in each room were tested for rhinovirus RNA. Transfer to fingertips of 5 subjects was examined by drying virus containing mucus from each subject onto light switches, telephone dial buttons and telephone handsets. After an interval of 1 or 18 hours the subject flipped the light switch, pressed the button, held the handset; 35% of the 150 sites in the rooms were contaminated. Common virus-positive sites were door handles, pens, light switches, TV remote controls, faucets, and telephones. Rhinovirus was transferred from surfaces to fingertips in 18/30 (60%) trials 1 hour after contamination and in 10/30 (33%) of trials 18 hours (overnight) after contamination.

“My five moments for hand hygiene”: a user-centred design approach to understand, train, monitor and report hand hygiene.
Sax H., Allegranzi B., Larson E., Boyce J., Pittet D. Journal of Hospital Infection 2007;67:9-21.
The WHO Global Patient Safety Challenge “Clean Care is Safer Care” has developed educational and promotional tools using a user-centred design approach and incorporating strategies of human factors engineering, cognitive behaviour science and elements of social marketing. This has resulted in a concept called “My five moments for hand hygiene” which describes the moments when hand hygiene is required to effectively interrupt microbial transmission during the care sequence. “My five moments for hand hygiene” bridges the gap between scientific evidence and daily health practice and provides a basis to understand, teach, monitor and report hand hygiene practices.

Prevalence of Clostridium difficile environmental contamination and strain variability in multiple health care facilities.
Dubberke E.R., Reske K.A., Noble-Wang J., Thompson A., Killgore G., Mafield J., Camins B., Woeltje K., McDonald J.R., McDonald L.C., Fraser V.J. American Journal of Infection Control 2007;35:315-8.
Forty-eight environmental samples were collected from six health care facilities. Samples were cultured for the presence of clostridium difficile (C. difficile). C. difficile was cultured from 13/48 (27%) samples. Rooms housing a patient with C. difficile-associated disease (CDAD) were more likely to be culture positive than non-CDAD patient rooms (100% vs. 33%); C. difficile was not isolated outside of patient rooms (0/12 samples). The NAP1 epidemic strain was found in 5/6 facilities.

Survival of epidemic strains of nosocomial- and community-acquired methicillin-resistant Staphylococcus aureus on coins.
Tolba O., Loughrey A., Goldsmith C.E., Millar B.C., Rooney P.J., Moore J.E. American Journal of Infection Control 2007;35:342-6.
This paper describes a study which demonstrates that all epidemic nosocomial- and community-acquired methicillin-resistant Staphylococcus aureus (MRSA) do not survive when no organic protection is offered but survive well when soil (pus and blood) is present, thus offering protection from drying.

Environmental contamination makes an important contribution to hospital infection.
Boyce J.M. Journal of Hospital Infection 2007; 65(Suppl 2 ):50-4.
This paper reviews the evidence for survival and transmission of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) in healthcare facilities. Environmental surfaces frequently touched by healthcare workers are commonly contaminated in the rooms of patients colonized or infected with MRSA or VRE. Studies document that healthcare workers may contaminate their hands or gloves by touching contaminated surfaces, and that hands or gloves become contaminated with numbers of organisms that are likely to result in transmission to patients. Pathogens may also be transferred directly from contaminated surfaces to susceptible patients. There is an increasing body of evidence that cleaning or disinfection of the environment can reduce transmission of healthcare-associated pathogens.

Importance of environmental decontamination a critical view.
Dettenkofera M., Spencer R.C. Journal of Hospital Infection 2007;65(Suppl 2):55-7.
The authors maintain that the level of evidence supporting different disinfection and cleaning procedures performed in healthcare settings worldwide is low. The final assessment of whether use of disinfectants rather than detergents alone reduces nosocomial infection rates in different clinical settings still awaits conclusive study. The decontamination ability of the substances used; prevention of resistance; and safety for patients, personnel and the environment; are the cornerstones that interact with each other. The authors conclude that targeted disinfection of environmental surfaces (those frequently touched) is an established component of infection control activities to prevent the spread of nosocomial pathogens, but of lesser importance than proper hand hygiene.

Decontamination of the environment.
Fraise A.P. Journal of Hospital Infection 2007;65(Suppl 2):58-9.
This paper reviews the evidence related to the impact of environmental cleaning and disinfection on transmission of infection in hospitals.

The First Global Patient Safety Challenge “Clean Care is Safer Care”: from launch to current progress and achievements.
Allegranzi B., Storr J., Dziekan G., Leotsakos A., Donaldson L., Pittet D., Journal of Hospital Infection 2007;
65 (Suppl 2): 115-23.
To meet the goal of ensuring patient safety across healthcare settings around the globe, the World Health Organization launched the World Alliance for Patient Safety in October 2004. Several initiatives have been undertaken to raise global awareness and to obtain country commitment to support action on this issue. The new Guidelines on Hand Hygiene in Health Care have been issued in draft form. An implementation strategy is proposed therein to provide solutions to overcome obstacles to improvement in compliance with hand hygiene practices, together with a range of practical tools.

Systematic risk assessment methods for the infection control professional.
Larson E., Aiello A.E. Am J Infect Control 2006; 34:323-6.
Microbial and infectious disease risk models are used to assess infectious hazards in the environment and identify strategies to prevent or reduce these hazards. Although risk modeling represents a promising approach, there are inherent limitations because of the multifactorial nature of the transmission of infections, the dynamic environment in which transmission takes place, and a paucity of available data to more fully specify model parameters. The purpose of this paper is to introduce processes adapted from the food and consumer industries, which could be applied to assess the risk of microbial transmission and the potential impact of interventions to prevent or control transmission in health care settings.

Handwashing and risk of respiratory infections: a quantitative systematic review.
Rabie T., Curtis V.. Tropical Medicine and International Health, 2006; 11 258-267
An evaluation of 8 eligible studies (from a primary list of 410 articles) showed that handwashing lowered risks of respiratory infection, with risk reductions ranging from 6% to 44% [pooled value 24% (95% CI 6–40%)]. Pooling the results of only the seven homogenous studies gave a relative risk of 1.19 (95% CI 1.12%–1.26%), implying that hand cleansing can cut the risk of respiratory infection by 16% (95% CI 11–21%). However, studies were of poor quality, none related to developing countries, and only one to severe disease.

Effectiveness of handwashing in preventing SARS: a review.
Chun-Hai Fung I. , Cairncross S . Tropical Medicine and International Health, 2006; 11 1749-1758 .
This review examines data literature on the effectiveness of handwashing as an intervention against SARS transmission. Nine of 10 studies showed that handwashing was protective against SARS when comparing infected cases and non-infected controls, but only in 3 studies was this result statistically significant. There is reason to believe that this is because most of the studies were too small. The authors conclude that the evidence for the effectiveness of handwashing as a measure against SARS transmission in health care and community settings is suggestive, but not conclusive.

Review of Aerosol Transmission of Influenza A Virus.
Tellier R. Emerging Infectious Disease s 2006 ; 12, 1657-1662 .
The paper is a review of the published findings that support the importance of aerosol transmission of influenza and a brief discussion on the implications of these findings on pandemic preparedness. Published evidence indicates that aerosol transmission of influenza can be an important mode of transmission, which has obvious implications for pandemic influenza planning and in particular for recommendations about the use of N95 respirators as part of personal protective equipment.

Salmonella Enteritidis in Broiler Chickens, United States, 2000–2005.
Altekruse S.F., Bauer N., Chanlongbutra A., DeSagun R., Naugle A. Emerging Infectious Diseases 2006 ; 12, 1848-1852 .
US data on Salmonella enterica serotype Enteritidis in broiler chicken carcass rinses collected 2000-2005 showed the annual number of isolates increased >4-fold and the proportion of establishments with Salmonella Enteritidis–positive rinses increased nearly 3-fold. US states with Salmonella Enteritidis in broiler rinses increased from 14 to 24. Recently, 2 US case-control studies identified eating chicken as a risk factor for sporadic human Salmonella Enteritidis infection replicating findings of a case-control study performed in England in the late 1980s. While the overall incidence of human salmonellosis was lower in 2005 than in the mid-1990s, the incidence of Salmonella Enteritidis infections was ˜25% higher.

Gastroenteritis and Transmission of Helicobacter pylori. Infection in Households.
Perry S., de la Luz Sanchez M., Yang S., Haggerty T.D., Hurst P., Perez-Perez G. and Parsonnet J. Emerging Infectious Diseases 2006, 12, 1701-1208 .
Household members in California USA were tested for H. pylori infection. Among 1,752 person considered uninfected at baseline, 30 new infections (7 definite, 7 probable, and 16 possible) occurred. Exposure to an infected household member with gastroenteritis was associated with a 4.8-fold increased risk for definite or probable new infection. Of probable/definite new infections, 75% were attributable to exposure to an infected person with gastroenteritis. The authors suggest that person-to-person transmission of H. pylori is most commonly implicated with fecal/oral, oral/oral, or gastric/oral pathways; infection is associated with conditions of crowding and poor hygiene and intrafamilial clustering.

Combining drinking water treatment and hand washing for diarrhoea prevention, a cluster randomised controlled trial.
Luby S.P., Agboatwalla M., Painter J., Altaf A., Billhimer W., Keswick J.B., Hoekstra R.M. Tropical Medicine & International Health 2006;11:479-89.
The study was conducted in squatter settlements of Karachi, Pakistan. Households in 10 neighbourhoods received diluted bleach and a water vessel; nine neighbourhoods received soap and were encouraged to wash hands; nine neighbourhoods received flocculent-disinfectant water treatment and a water vessel; 10 neighbourhoods received disinfectant-disinfectant water treatment and soap and were encouraged to wash hands; and nine neighbourhoods were followed as controls. Study participants in control neighbourhoods had diarrhoea on 5.2% of days. Compared to controls, participants living in intervention neighbourhoods had a lower prevalence of diarrhoea: 55% lower in bleach and water vessel neighbourhoods, 51% lower in hand washing promotion with soap neighbourhoods, 64% lower in disinfectant-disinfectant neighbourhoods, and 55% lower in disinfectant-disinfectant plus hand washing with soap neighbourhoods. Although each of the home-based interventions significantly reduced diarrhoea, there was no benefit by combining hand washing promotion with water treatment.

Etiology and epidemiology of diarrhea in children in Hanoi, Vietnam.
Vu Nguyen T.,Le Van P, Le Huy C, Nguyen Gia K, Weintraub A. International Journal of Infectious Disease 2006;10:298-308.
The study compared 587 children with diarrhoea with 249 age matched healthy controls, to assess the main epidemiological factors contributing to diarrheal disease in children. More children got diarrhoea in (i) poor families; (ii) families where piped water and a latrine were lacking; (iii) families where mothers washed their hands less often before feeding the children; (iv) families where mothers had a low level of education; (v) families where information on health and sanitation less often reached their households.

A systematic review of the evidence for interventions for the prevention and control of meticillin-resistant Staphylococcus aureus (1996-2004): report to the Joint MRSA Working Party (Subgroup A).
Loveday H.P., Pellowe C.M., Jones S, Pratt R. Journal of Hospital Infection 2006;63(suppl 1):S45-70.
This paper reviews evidence published between 1996 and 2004 on the effectiveness, and associated economic costs, of a range of interventions to prevent and control the transmission of meticillin-resistant Staphylococcus aureus (MRSA) in hospital settings. The review questions focused on screening, patient isolation, use of decolonisation strategies, feedback of surveillance data, and environmental hygiene interventions. The methodological quality of studies retrieved was such that there is currently insufficient high-quality evidence for infection prevention and control interventions in the fields identified for this review. However, evidence from clinically based, non-experimental studies does provide support for continued use of a range and combination of interventions that contribute to the prevention and control of MRSA within acute hospitals and long-term care settings.

Cost effectiveness of home-based chlorination and safe water storage in reducing diarrhea among HIV-infected households in rural Uganda.
Shrestha R.K., Marseille E., Kahn J.G., Lule J.R., Pitter C., Blandford J.M., Bunnell R., Courinho A., Kizitio F., Quick R., Mermin J. American Journal of Tropical Medicine and Hygiene 2006;74:884-90.
This study examined the cost-effectiveness of a safe water system (SWS) for HIV-affected households using health outcomes and costs from a randomised controlled trial in Tororo, Uganda. SWS was part of a home-based health care package that included rapid diarrhoea diagnosis and treatment of 196 households with relatively good water and sanitation coverage. SWS use averted 37 diarrhoea episodes and 310 diarrhoea-days, representing 0.155 disability-adjusted life year (DALY) gained per 100 person-years, but did not alter mortality. Net programme costs were $5.21/episode averted, $0.62/diarrhoea-day averted, and $1,252/DALY gained. The high SWS cost per DALY gained was probably caused by a lack of mortality benefit in a trial designed to rapidly treat diarrhoea. SWS is an effective intervention whose cost-effectiveness is sensitive to diarrhoea-related mortality, diarrhoea incidence, and effective clinical management.

Water, sanitation and hygiene interventions to reduce diarrhoea in less developed countries: a systematic review and meta-analysis.
Fewtrell L., Kaufmann R.P., Kay D., Enanario W., Huller L., Colford J.M. Lancet Infectious Diseases 2005;5:42-52.
This paper presents a systematic review of all published studies and, where appropriate, meta-analysis of studies that reported interventions in water quality, water supply, hygiene and sanitation in less developed countries. The meta-analyses focus on the evidence for any change arising from the interventions in diarrhoeal disease occurrence in non-outbreak conditions.

The effect of enhanced hygiene practices on absences due to infectious diseases among children in day care centers in Helsinki.
Ponka, A., Opoussa, T. and Laosmaa, M. Infection 2004;32:2-7.
The study was conducted as an open, controlled cluster study. It included 60 DCCs for intervention and 228 DCCs as controls. The hygiene intervention program included 8 steps such as intensified handwashing among both children and staff, washing toys weekly, surfaces reachable by children were washed daily. The control DCC continued to follow their usual hygiene policies and practices. The main indicator was the occurrence of absences due to upper respiratory tract infections, otitis media, eye infection and diarrhea per child-month. In the intervention DCC absences due to infections reduced by 26% among under 3-year olds, but not among older children.

Inoculum Size Influences Bacterial Cross Contamination between Surfaces.
Montville R., Schaffner D.W. Applied and Environmental Microbiology, Dec. 2003, p. 7188–7193 Vol. 69, No. 12.
A study of transfer between surfaces showed that the effect of inoculum size on transfer rate was highly statistically significant for all transfer rate data, except for data on contamination via transfer from chicken to hand through a glove barrier. Where inoculum size was greater, transfer rates were lower, and where inoculum size was less, transfer rates were higher. The negative linear trend has serious implications for research seeking to determine bacterial cross contamination rates, since transfer efficiencies that were previously shown to be associated with certain activities may actually be the result of differing initial inoculum levels.

Bacterial transfer and cross-contamination potential associated with paper-towel dispensing.
Harrison W.A., Griffith C.J., Ayers T. and Michaels B. American Journal of Infection Control 2003; 31: 387-391.
Volunteers with clean or contaminated hands were asked to remove towels from dispensers which themselves were either clean or contaminated. Recoverable bacterial transfer rates from contaminated hands to clean dispensers ranged from 0.01% to 0.64% depending on the bacteria used. The reverse transfer (i.e., from contaminated exits to clean hands) was between 12.4% and 13.1%. The results indicate that transfer of bacteria between paper-towel dispensers and hands can take place if either one is contaminated.

Cost effectiveness of a targeted disinfection program in household kitchens to prevent foodborne illnesses in the United States, Canada and the United Kingdom.
Duff, S.B., Scott, E.A., Mafilios, M.S., Todd, E.C., Krilov, L.R., Geddes, A.M. and Ackerman, S.J. J Food Protect 2003;66:2103-2115.
A computer-based economic model was developed to evaluate the potential cost-effectiveness of a targeted disinfection program for high-risk food preparation in household kitchens. For US, Canada and UK, published literature and expert opinion was used to estimate the cost of the program, the number of cases of Salmonella, Campylobacter, and E. coli O157:H7 infections prevented, and the economic and quality-of-life outcomes. The model estimated that approximately 80,000 infections could be prevented annually in US homes, resulting in $138 million in direct medical cost savings, 15,845 quality-adjusted life-years (QALYs) gained, $788 million in program costs. Results were similar for households in Canada and the UK. Implementing a targeted disinfection program in household kitchens in the US, Canada, and UK appears to be a cost-effective strategy. When evaluating the program for households with high-risk members, the cost-effectiveness was more favourable.

Chlorination and safe storage of household drinking water in developing countries to reduce waterborne disease.Sobsey MD, Handzel T, Venczel L. Water Sci Technol 2003;47(3):221-8
This study evaluated point-of-use chlorination and storage in special plastic containers of gathered household water for improving microbial quality and reducing diarrhoeal illness of consumers living under conditions of poor sanitation and hygiene. There were intervention groups who had household water chlorination and storage in a special container, and control households with no interventions. The use of interventions significantly improved the microbiological quality of the non-piped household drinking water. Episodes of household diarrhoeal illness were lower in the intervention families compared to control families, indicating that community diarrhoea was preventable by using the interventions. Widespread use of simple treatment and storage for non-piped domestic water could dramatically reduce the global burden of waterborne diarrhoeal disease.