4. HYGIENE PRACTICE; HOW

Introduction
Having identified the hazards and relative risks in the home, it becomes possible to develop policies on appropriate hygiene procedures for implementation in each situation. Generally, there are a number of decontamination practices which can be encouraged in the home to ensure that food is wholesome to eat, and that sites and surfaces which represent potential for cross-contamination are hygienically clean and not just visibly clean. These include drying, detergent and hot water washing, and heat or chemical disinfection.

It is important to stress that the effectiveness of any hygiene procedure applied in the home depends not only on the effectiveness of the procedure, (e.g. the hygienic cleaner or disinfectant) but also on the way in which it is applied, i.e. in the right way and at the right time.

This section of the library contains recent information on the effectiveness and limitations of various processes for achieving hygiene of the hands and environmental surfaces in the domestic setting.

Selected articles

Hot hospitals and what happened to wash, rinse and dry? Recent changes to cleaning, disinfection and environmental ventilation.
Pricea EH, Ayliffeb G. Journal of Hospital Infection. 2008;69:89-98.
This paper discusses the recommendations on ventilation: wash, rinse, and drying of surfaces and clean of equipment using heat methods in the control of hospital associated infections.

Use of murine norovirus as a surrogate to evaluate resistance of human norovirus to disinfectants.
Belliot G, Lavaux A, Souihel D, Agnello D,  Pothier P. Applied and Environmental Microbiology. 2008;3315-18.
Murine norovirus (MNV) was used as a surrogate to study resistance of human norovirus to disinfectants used in hospitals. MNV was sensitive to alcohol, alcohol hand rubs, bleach, and povidone iodine-based disinfectant. Real-time reverse transcription-PCR results indicated that the presence of viral RNA did not correlate with the presence of infectious virus.

Decontamination of Fluid Milk Containing Bacillus Spores Using Commercial Household Products.
Black DG, Taylor TM, Kerr HJ, Padhi S, Montville TJ, Davidson PM. Journal of Food Protection. 2008;71(3):473–8.
Although commercial sanitizers can inactivate bacterial spores in food processing environments, relatively few data exist on the decontamination of products and surfaces using household products. Should a large scale bioterrorism incident occur in which consumer food products were contaminated with a pathogenic sporeformer such as Bacillus anthracis, there might be a need to decontaminate these products before disposal as liquid or solid waste. Studies were conducted to test the efficacy of household products for inactivating spores of Bacillus cereus  in vitro and in fluid milk. Validation of the resistance of the B. cereus spores was confirmed with B. anthracis spores. The resistance of spores of surrogate B. cereus strains to chlorine-containing compounds was similar to that of B. anthracis spores. Therefore, several household products on the market may be used to decontaminate fluid milk or similar food products contaminated by spores of B. anthracis.

Assessment of a low-cost, point-of-use, ultraviolet water disinfection technology.
Brownell SA, Chakrabarti AR, Kaser FM, Reygadas F, Lang MJ, Connelly LG, et al. Journal of Water and Health. 2008;6(1):53–65.
We describe a point-of-use (POU) ultraviolet (UV) disinfection technology, the UV Tube, which can be made with locally available resources around the world for under $50 US. Laboratory and field studies were conducted to characterize the UV Tube's performance when treating a flowrate of 5 L/min. A small field study in two rural communities in Baja California Sur demonstrated that the UV Tube reduced E. coli concentrations to less than 1/100 ml in 65 out of 70 samples. The results demonstrate that the UV Tube is a promising technology for treating household drinking water at the point of use.

Are hygiene standards useful in assessing infection risk?
White LF, Dancer SJ, Robertson C, McDonald J. Am J Infect Control. 2008;36:381-4.
We monitored the surface level cleanliness in a 5-bed surgical intensive care unit (SICU) over a 10-week period to evaluate proposed hygiene standards. Ten environmental sites within the SICU were sampled twice weekly, along with collection of clinical and patient activity data. The standards designate aerobic colony counts (ACCs) > 2.5 colony-forming units/cm2 from hand-touch sites and the presence of Staphylococcus aureus as indicating hygiene failure. The results demonstrate that hygiene standards based on microbial growth levels and the presence of S aureus reflect patient activity and provide a means to risk-manage infection. They also expose a staphylococcal reservoir that could represent a more tangible risk to patients. Standards for surface level cleanliness merit further evaluation

Importance of the environment in meticillin-resistant Staphylococcus aureus acquisition: the case for hospital cleaning.
Dancer SJ. http://infection.thelancet.com. Published online October 31, 2007.
In the UK, we continue to debate the importance of hospital cleaning in relation to increasing numbers of patients acquiring meticillin-resistant Staphylococcus aureus (MRSA). However, there is little direct evidence for the effectiveness of cleaning because it has never been afforded scientific status. This review will show why the removal of dirt might have more impact on the control of MRSA than previously thought. Introduction of additional cleaning services is easier than improvements in hand-hygiene compliance.

Cross-contamination in the kitchen: effect of hygiene measures.
de Jong AEI, Verhoeff-Bakkenes L, Nauta MJ, de Jonge R. Journal of Applied Microbiology (2008).
This study sought to determine the effect of hygiene measures on cross-contamination of Campylobacter jejuni at home and to select a safe tracer organism for C. jejuni. Comparative tests were conducted with non-pathogenic Escherichia coli and Lactobacillus casei and L. casei was chosen as the safe tracer organism. The results led us to conclude that dish-washing does not sufficiently prevent cross-contamination. Lactobacillus casei can be used as a safe tracer organism for C. jejuni in consumer observational studies. Cross-contamination plays an important role in the transmission of food-borne illness, especially for C. jejuni. This study delivers suitable data to quantitatively assess the risk of campylobacteriosis caused by cross-contamination and it shows the effect of different preventive hygiene measures.

Disinfection of Bacillus subtilis spore-contaminated surface materials with a sodium hypochlorite and a hydrogen peroxide-based sanitizer.
DeQueiroz GA., Day DF. Letters in Applied Microbiology (2008).
We evaluated a sodium hypochlorite and hydrogen peroxide solution (Ox-B7) as a potential decontaminant of Bacillus subtilis spore-contaminated surface materials (porous and nonporous). Test materials were contaminated with B. subtilis spores to a final concentration in the range of 5.7–6.6 log CFU cm-2. The results demonstrated that a combination of sodium hypochlorite and hydrogen peroxide (Ox-B7) effectively killed B. subtilis spores on both porous and nonporous surface materials. Therefore, the combination of sodium hypochlorite and hydrogen peroxide can be used as an alternative disinfectant of spore-contaminated surface materials, as it is more effective than when hydrogen peroxide or sodium hypochlorite are used separately.

Speeding up solar disinfection (SODIS): effects of hydrogen peroxide, temperature, pH, and copper plus ascorbate on the photoinactivation of E. coli.
Fisher MB, Keenan CR, Nelson KL, Voelker BM. Journal of Water and Health. 6(1):35–51.
Solar disinfection, or SODIS, shows tremendous promise for point-of-use drinking water treatment in developing countries, but can require 48 h or more for adequate disinfection in cloudy weather. In this research, we show that a number of low-cost additives are capable of accelerating SODIS. Laboratory and field experiments indicated that additives might make SODIS more rapid and effective in both sunny and cloudy weather, developments that could help make the technology more effective and acceptable to users.

Alternative hand contamination technique to compare the activities of antimicrobial and nonantimicrobial soaps under different conditions.
Fuls JL, Rodgers ND, Fishler GE, Howard JM, Patel M, Weidner PL, et al. Applied and Environmental Microbiology. 2008;3739-44.
The aim of this work was to examine the effects of wash time and soap volume on the relative activities and the subsequent transfer of bacteria to inanimate objects for antimicrobial and nonantimicrobial soaps. The results indicated that nonantimicrobial soap was less active and that the effectiveness of antimicrobial soaps can be improved with longer wash time and greater soap volume. The transfer of bacteria to objects was significantly reduced due to greater reduction in bacteria following the use of antimicrobial soap.

Comparative Inactivation of Enteroviruses and Adenovirus 2 by UV Light.
Gerba CP, Gramos DM, Nwachuku N. Applied and Environmental Microbiology. 2002;5167–69.
The doses of UV irradiation necessary to inactivate selected enteric viruses on the U.S. Environmental Protection Agency Contaminant Candidate List were determined. Three-log reductions of echovirus 1, echovirus 11, coxsackievirus B3, coxsackievirus B5, poliovirus 1, and human adenovirus type 2 were effected by doses of 25, 20.5, 24.5, 27, 23, and 119 mW/cm2, respectively. Human adenovirus type 2 is the most UV light-resistant enteric virus reported to date.

In-vivo efficacy of hand sanitisers against feline calicivirus: a surrogate for norovirus.
Lages SLS, Ramakrishnan MA, Goyal SM. Journal of Hospital Infection. 2008;68:159-63.
We investigated the virucidal efficacy of nine hand sanitisers (four alcohol-based sanitisers, three non-alcoholic sanitisers and two triclosan-containing antimicrobial liquid soaps) against feline calicivirus, a surrogate for norovirus, on artificially contaminated fingertips for 30 s and 2 min contact periods. The results indicate that triclosan-containing antimicrobial soaps or alcohol-based hand rubs may be inadequate for preventing norovirus transmission. Further research on alternative hand sanitisers should continue for effective control of norovirus infections.

Efficacy of Sodium Hypochlorite-Based Disinfectants against Clostridium difficile Spores.
Holtschlag J. BS. Infection Control and Hospital Epidemology. 2008;29(2).
This paper discusses the efficacy of sodium hypochlorite-based disinfectants against Clostridium difficile spores in relation to the methods used.

How effective are hand antiseptics for the postcontamination treatment of hands when used as recommended?
Kampf G. AJIC. 2008;36(5):356-60.
We investigated the efficacy of 2 different volumes of 4 marketed hand rubs when applied to contaminated hands. Hands of 16 volunteers were contaminated with Serratia marcescens. Hand rub A (85% ethanol), hand rub B (60% ethanol), hand rub C (62% ethanol), and hand rub D (61% ethanol) were applied as blinded formulations, each in single applications of 2.4 or 3.6 mL. Hibiclens (4% chlorhexidine gluconate) served as the reference treatment. Each hand rub was rubbed into the hands until dry. Pre-intervention and post-intervention bacterial populations were obtained by the glove juice method. Neutralization of residual activity was validated. The results indicated that hand rubs applied in amounts sufficient to cover both hands may not reduce the bacterial density by even 2 log10 steps. Based on our findings, the general trend toward alcohol-based hand rubs should not overlook evidence of significant differences in efficacy that appear to be related primarily to a product's overall concentration of alcohol.

Solar UV reduces Cryptosporidium parvum oocyst infectivity in environmental waters.
King BJ., Hoefel D, Daminato DP, Fanok S, Monis PT. Journal of Applied Microbiology. 2008;(104):1311–23.
This study sought to determine the effect of solar radiation on Cryptosporidium parvum in tap and environmental waters. Outdoor tank experiments and a cell culture infectivity assay were used to measure solar inactivation of C. parvum oocysts in different waters. The results concluded that Solar UV can rapidly inactivate C. parvum in environmental waters. This is the first study to assess natural sunlight inactivation of C. parvum oocysts in surface waters and drinking water using an infectivity measure and determines the wavelengths of light responsible for the inactivation. The findings presented here provide valuable information for determining the relative risks associated with Cryptosporidium oocysts in aquatic environments and identify solar radiation as a critical process affecting the oocyst survival in the environment.

Hydrogen peroxide vapour decontamination in the control of a polyclonal meticillin-resistant Staphylococcus aureus outbreak on a surgical ward.
Drydena M, Parnabya R, Daillya S, Lewisa T, Davis-Bluesa K, J.A. Otter, et al. Journal of Hospital Infection. 2008;1-3.
The paper describes a study showing that several interventions, including patient and staff decolonisation combined with environmental decontamination, were associated with termination of an outbreak of MRESA on a surgical ward.. It is therefore difficult to discern which intervention(s) were most effective but it would appear that the reduction in MRSA environmental load removed a substantial reservoir of MRSA that may otherwise have resulted in a continuation of the outbreak.

Reducing Absenteeism from Gastrointestinal and Respiratory Illness in Elementary School Students: A Randomized, Controlled Trial of an Infection-Control Intervention.
Thomas J, Sandora TJ, Shih M-C, Goldmann DA. Pediatrics. 2008;121:1555-62.
We performed a school-based cluster-randomized, controlled trial at a single elementary school. Eligible students in third to fifth grade were enrolled. Intervention classrooms received alcohol-based hand sanitizer to use at school and quaternary ammonium wipes to disinfect classroom surfaces daily for 8 weeks; control classrooms followed usual hand-washing and cleaning practices. Parents completed a preintervention demographic survey. A total of 285 students were randomly assigned; baseline demographics were similar in the 2 groups. The adjusted absenteeism rate for gastrointestinal illness was significantly lower in the intervention-group subjects compared with control subjects. The adjusted absenteeism rate for respiratory illness was not significantly different between groups. Norovirus was the only virus detected and was found less frequently on surfaces in intervention classrooms compared with control classrooms (9% vs 29%).

Inactivation of Cryptosporidium parvum under chlorinated recreational water conditions.
Shields JM, Hill VR, Arrowood MJ, Beach MJ. J Water Health. 2008;6(4):513-20.
In the present study, free chlorine Ct values were measured at pH 7.5 using young oocysts (<1 month old) and tissue culture to determine oocyst viability. Two different oocyst isolates were used: one originating from Iowa and one from Maine (USA). This study determined that the Ct values for a 3-log reduction in oocyst viability were 10,400 (Iowa) and 15,300 (Maine) at pH 7.5. These Ct values are higher than the Centers for Disease Control and Prevention (USA) currently recommends (Ct=9,600) for achieving a 3.0-log inactivation of Cryptosporidium oocysts during remediation of recreational water venues following fecal diarrhea accidents.

Impact of jerry can disinfection in a camp environment - experiences in an IDP camp in Northern Uganda.
Steele A, Clarke B, Watkins O. J Water Health. 2008;6(4):559-64.
In July 2007, a study by the Centre for Environmental Health Engineering, at the University of Surrey, assessed a modified method of jerry can cleaning in an internally displaced persons (IDP) camp in Kitgum, N. Uganda. Jerry cans were disinfected using high strength sodium hypochlorite (NaOCl) generated using an experimental AquaChlor Solar unit. The study suggested that regular jerry can cleaning, using a high strength chlorine based disinfectant, offers an effective method of alleviating the adverse effects of contamination in water collection and storage vessels. Results indicated that the method is capable of significantly reducing thermo-tolerant coliform numbers to below 5 cfu/100 ml in most cases. Chlorine strength depletion after repetitive cleaning confirms the impact of the process. It is suggested that the process can play an important role during outbreaks of water-borne diseases, such as cholera, particularly if combined with regular water disinfection.

How effective is good domestic kitchen hygiene at reducing diarrhoeal disease in developed countries? A systematic review and reanalysis of the UK IID study.
Stenberg A, Macdonald C, Hunter PR. BMC Public Health 2008;8:71.
This review assessed whether domestic kitchen hygiene is an important contributor to the development of diarrhoea in the developed world. Electronic searches were carried out in October 2006 in EMBASE, MEDLINE, Web of Knowledge, Cochrane central register of clinical trials and CINAHL. All publications, irrespective of study design, assessing food hygiene practices with an outcome measure of diarrhoea were included in the review. Of the 14 studies included in this systematic review, 11 were case-control studies, 2 cross-sectional surveys, and 1 RCT. Very few studies identified any significant association with good environmental kitchen hygiene. Although some of the variables in the reanalysis of the UK IID study were statistically significant no obvious trend was seen. The balance of the available evidence does not support the hypothesis that poor domestic kitchen hygiene practices are important risk factors for diarrhoeal disease in developed countries.

Pathogen survival in the external environment and the evolution of virulence.
Walther BA, Ewald PW. Biol Rev. 2004;(79):849-69.
Recent studies have provided evolutionary explanations for much of the variation in mortality among human infectious diseases. One gap in this knowledge concerns respiratory tract pathogens transmitted from person to person by direct contact or through environmental contamination. The sit-and-wait hypothesis predicts that virulence should be positively correlated with durability in the external environment because high durability reduces the dependence of transmission on host mobility. Reviewing the epidemiological and medical literature, we confirm this prediction for respiratory tract pathogens of humans.

Investigation into the effect of detergents on disinfectant susceptibility of attached Escherichia coli and Listeria monocytogenes.
Walton JT,  Hill DJ, Protheroe RG, Nevill A, Gibson H. Journal of Applied Microbiology (2008).
We investigated the effects of detergent treatment on the susceptibility of attached Escherichia coli and Listeria monocytogenes to subsequent disinfectant treatment. The results demonstrate that, in E. coli, detergents that increase susceptibility to BAC increase membrane permeability. In L. monocytogenes, detergents that reduce susceptibility to BAC lower cell surface hydrophobicity.
Detergents, therefore, can influence the sensitivity of pathogenic food borne micro-organisms to BAC.

Disinfection of Burkholderia cepacia complex from non-touch taps in a neonatal nursery.
Kotsanas D, Brett J, Kidd TJ, , Korman TM. J Perinat Med. 2008;36(3):235-9.
B. cepacia was identified from the blood culture of a baby in a neonatal unit (NU) in March 2005. Environmental samples were collected from the NU, including tap water from non-touch taps. B. cenocepacia has been known to cause nosocomial outbreaks and it was eventually eradicated from the NU by using repeated thermal shock (hot water at 65 degrees C for 10 min), changing taps and decolonizing sinks with hypochlorite.

Maternal and Birth Attendant Hand Washing and Neonatal Mortality in Southern Nepal.
Rhee V, Mullany LC, Khatry SK, Katz J, LeClerq SC, Darmstadt GL, et al. Arch Pediatr Adolesc Med. 2008;162(7):603-608.
In this study in rural Nepal, 23,662 newborn infants were enrolled in a community-based trial assessing the effect of skin and/or umbilical cord cleansing with chlorhexidine on neonatal mortality through 28 days of life. The study showed that birth attendant hand washing was related to a statistically significant lower mortality rate among neonates (adjusted relative risk [RR]=0.81), as was maternal hand washing (adjusted RR=0.56). There was a 41% lower mortality rate among neonates exposed to both hand-washing practices (adjusted RR=0.59).

A clarion call for greater investment in global sanitation.
Durrhein D. Lancet 2007;370:1592-3.
Diarrhoeal disease continues to be a leading cause of death in developing countries, particularly affecting children in the first 5 years of life. The hindrance on global development resulting from inadequate sanitation is recognised in the MDGs, and a target to halve the proportion of people without access to basic sanitation by 2015 has been established. Although global sanitation coverage increased from 49% to 59% between 1990 and 2004, on the basis of current performance the shortfall will be almost 600 million people by the target date in 2015. The vigour with which other MDGs have been approached has not yet been mirrored in tackling the sanitation shortfall. Indeed, in sub-Saharan Africa the number of people with unsafe sanitation is increasing.

Severe case of invasive community-acquired methicillin-resistant Staphylococcus aureus infection in Norway.
Heggelund L., Samdal H.H., Eggum R., Jacobsen T., Bruun T., Elstrøm P. Eurosurveillance 2007; vol 12, issue 11, 8 Nov.
In Norway the rate of MRSA colonisation and infection is low, but rapidly increasing. The proportion of severe invasive MRSA infections has remained low, and up to now all infections diagnosed outside hospitals have been non-severe skin and soft tissue infections. MRSA harbouring ST80, SCCmec IV and PVL are characteristic for community-acquired strains. This report describes, for the first time, a CA-MRSA strain with such properties causing a very severe invasive thoracic wall infection in Norway.

Public health measures in an influenza pandemic – the importance of surveillance.
Nicoll A. Eurosurveillance 2007: vol 12, issue 11, 1 Nov.
One of the most controversial aspects of planning for a pandemic concerns public health measures that could reduce its impact. There are many measures it is proposed could be taken with the aim of pushing back the bulk of transmission towards the natural decline that occurs in the warmer summer months, and when specific pandemic vaccines become available. In Europe, it is unlikely that “one size will fit all” except for the few measures that are at the “relatively easy” (handwashing and personal respiratory hygiene) or “very difficult – don’t do it” (border closure) extremes. Even if simple solutions were possible, it is not in the mandate of the ECDC to prescribe policy. To inform discussions and decisions by member states and EU bodies, ECDC have published an interim Guide to Public Health Measures to Reduce the Impact of Influenza Pandemics during Phase 6 - “The ECDC Menu”. The primary intended audience is those who develop policy and decision makers, although secondary audiences are all those concerned with influenza, the public and the media.

Microbiologic evaluation of microfiber mops for surface disinfection.
Rutala W.A., Gergen M.F., Webber D.J. American Journal of Infection Control 2007;35(9): 569-73.
The effectiveness of microfiber mops to reduce microbial levels on floors was investigated. We compared the efficacy of microfiber mops with that of conventional, cotton string mops in 3 test conditions (cotton mop and standard wringer bucket, microfiber mop and standard wringer bucket, microfiber system). The microfiber system demonstrated superior microbial removal compared with cotton string mops when used with a detergent cleaner. The use of a disinfectant did not improve the microbial elimination demonstrated by the microfiber system.

Effect of chlorhexidine and benzalkonium chloride on bacterial biofilm formation.
Houari A., Di MartinoP. Letters in Applied Microbiology 2007;45:652-6.
The study showed that chlorhexidine and benzalkonium chloride inhibited biofilm formation of different bacterial species but were able to induce biofilm development for Staph. epidermidis at sub-MICs. The study suggests that sublethal exposure to cationic antiseptics may contribute to the persistence of staphylococci through biofilm induction.

Consumer antibacterial soaps: effective or just risky?
Aiello A.E., Larson E.L., Levy S.B. Clinical Infectious Diseases 2007:45(suppl 2):S137-47.
This systematic literature review assessed studies that examined the efficacy of products containing triclosan, compared with that of plain soap, in the community setting, and evaluated findings of studies carried out to evaluate the emergence of antibiotic resistant bacteria associated with their use. The PubMed database was searched, using relevant keyword combinations, for articles published between 1980 and 2006; 27 studies were identified as being relevant to the review. Soaps containing triclosan within the range of concentrations commonly used in the community setting (0.1%-0.45% wt/vol) were no more effective than plain soap at preventing infectious illness symptoms and reducing bacterial levels on the hands. The authors concluded that several laboratory studies demonstrated evidence of triclosan-adapted cross resistance to antibiotics.

Effect of city-wide sanitation programme on reduction in rate of childhood diarrhoea in northeast Brazil: assessment by two cohort studies.
Barreto M.L., Genser B., Strina A., et al. Lancet 2007;370:1622-8.
A city-wide sanitation intervention was started in Salvador, Brazil, in 1997 to improve sewerage coverage from 26% of households to 80%. The aim was to investigate the epidemiological effect of this city-wide sanitation programme on diarrhoea morbidity in children less than 3 years of age. Diarrhoea prevalence fell by 21% (95% CI 18-25%) - from 9.2 (9.0-9.5) days per child-year before the intervention to 7.3 (7.0-7.5) days per child-year afterwards. After adjustment for baseline sewerage coverage and potential confounding variables, overall prevalence reduction was estimated as 22% (19-26%).

The effectiveness of existing and modified cleaning regimens in a Welsh hospital.
Griffith C.J., Obee P., Cooper R.A., Burton N.F., Lewis M. Journal of Hospital Infection 2007;66:352-9.
The effectiveness of an existing ward-cleaning regimen was assessed at selected sites over 14 days and shown to be highly variable. The cleaning regimen was subsequently modified in two stages, both changes involving a rinse stage and substituting cloths with disposable paper towels. One modification continued using the existing detergent; the other replaced detergent with a quaternary ammonium sanitiser. Both modifications yielded significantly lower and more consistent bacterial counts. Assessment of residual organic soil using ATP detection demonstrated that failure rates (measurements exceeding benchmark clean value of 500 relative light units fell from 86-100% after existing cleaning methods, to 0-14% after modified cleaning. Incorporating quaternary ammonium sanitiser into the cleaning regimen produced a further slight, but not significant, improvement in cleaning efficacy.

Importance of the environment in methicillin-resistant Staphylococcus aureus acquisition: the case for hospital cleaning.
Dancer S.J. Lancet 2007; 369:442-3.
In the UK, we continue to debate the importance of hospital cleaning in relation to increasing numbers of patients acquiring methicillin-resistant MRSA. However, there is little direct evidence for the effectiveness of cleaning because it has never been afforded scientific status. This detailed review of the evidence which shows why removal of dirt might have more impact on the control of MRSA than previously thought.

Environmental decontamination with hydrogen peroxide vapor (HPV) in the control of an MRSA outbreak.
Otter J. Abstracts of the International Conference on Antimicrobial Agents and Chemotherapy, K-464.
Following a UK hospital outbreak of MRSA, where it was not possible to empty the ward, the ward was decontaminated using HPV in sequential clinical areas and assessed the level of environmental contamination before and after. Weekly swabbing was then carried out to examine the rate of recontamination and monitored patient infection by admission and discharge screening over four weeks. There was a sustained environmental impact and no patients acquired MRSA for the 4 weeks after HPV. The authors found a fairly high staff carriage rate and conducted patient and staff decolonization in addition to the HPV decontamination and other infection control measures so were not able to conclude which was the most important intervention.

After the flood: an evaluation of in-home drinking water treatment with combined flocculent-disinfectant following Tropical Storm Jeanne – Gonaives, Haiti, 2004.
Colindres R.E., Jain S., Bowen A., Mintz E., Domond P. Journal of Water and Health 5(3):367-74.
During a tropical Storm in Haiti in September 2004 local leaders distributed PūR®, a flocculent-disinfectant product for household water treatment, to affected populations. Knowledge, attitudes, practices, and drinking water quality was evaluated. After distribution, PūR® was the most common in-home treatment method (58%) followed by chlorination (30%), plant-based flocculation (6%), boiling (5%), and filtration (1%). Although water sources tested appeared clear, fecal coliform bacteria were detected in all sources (range 1 - >200 cfu/100 ml). Chlorine was present in 10 (45%) of 22 stored drinking water samples in households using PūR®.

New water disinfection system using UVA light-emitting diodes.
Hamamoto A., Mori M., Takahashi A., et al. Journal of Applied Microbiology 2007;2291-8.
This study evaluated a new disinfection device equipped with high-energy UVA-LED. Vibrio parahaemolyticus, enteropathogenic Escherichia coli, Staphylococcus aureus and Escherichia coli DH5α were reduced by greater than 5-log10 stages within 75 min at 315 J cm2 of UVA. Salmonellaenteritidis was reduced greater than 4-log10 stages within 160 min at 672 J cm2 of UVA.

Inactivation of Bacillus anthracis spores by liquid biocides in the presence of food residue.
Hilgren J., Swanson K.M., Diez-Gonzalez F., Cords B. Applied Environmental Microbiology 2007;73:6370-7.
Biocide inactivation of Bacillus anthracis spores in the presence of food residues after a 10 minute treatment time was investigated. Inoculated carriers were exposed to various concentrations of peroxyacetic acid, sodium hypochlorite (NaOCl) or hydrogen peroxide (H2O2) for 10 minutes. This research provides new information regarding the usefulness of peroxygen biocides for B. anthracis spore inactivation when food residue is present. This work also provides guidance for adjusting decontamination procedures for food-soiled and cold surfaces.

Outbreak management and implications of a nosocomial norovirus outbreak.
Johnston CP, Qiu H, Ticehurst JR, et al. Clinical Infectious Diseases 2007;45(5):534-40.
The study identified 355 cases that affected 90 patients and 265 healthcare workers and that were clustered in the coronary care unit and psychiatry units. Attack rates were 5.3% (7 of 133) for patients and 29.9% (29 of 97) for healthcare workers in the coronary care unit and 16.7% (39 of 233) for patients and 38.0% (76 of 200) for healthcare workers in the psychiatry units. Aggressive infection-control measures, including closure of units and thorough disinfection using sodium hypochlorite, were required to terminate the outbreak. Costs associated with this outbreak were estimated to be $657,644. The authors conclude that the significant disruption of patient care and cost of the outbreak support aggressive efforts to prevent transmission of noroviruses in health care settings.

Hand washing: changes in the skin flora.
Gerais M. American Journal of Infection Control 2007;35:417-20.
Frequent hand washing may result in skin damage and increase the number of microorganisms that colonize the skin. The purpose of this study was to evaluate changes in total flora of healthy and damaged hands that were caused by the use of gloves, soap, and antiseptics. Damaged or healthy hands did not present statistically significant differences (p>.05) in terms of qualitative analysis of epidemiologically important microorganisms; however, washing with water and soap was effective only for healthy hands.

Early communication: does a national campaign to improve hand hygiene in the NHS work? Initial English and Welsh experience from the NOSEC study (National Observational Study to Evaluate the CleanYourHandsCampaign).
Gould D.J., Hewitt-Taylor J., Drey N.S., Gammon J., Chudleigh J., Weinberg J.R. Journal of Hospital Infection 2007;66:293-6.
The NPSA “CleanYour HandsCampaign” seeks to improve healthcare workers’ hand-hygiene behaviour and was rolled out to 187 hospitals between December 2004 and June 2005.It consists of provision of “near-patient alcohol hand rub at the bedside”, “talking walls” (posters on each ward changed every month) and “patient empowerment” (materials telling patients to ask HCWs to clean their hands). The aims of the NOSEC study are to determine whether the campaign is implemented successfully and sustained, whether it results in increased hand hygiene, and to document changes in healthcare-associated infection rates. This communication reports on changes in soap and AHR use and HCAI rates in the baseline and roll out phases, and on implementation of main CYHC components at 6 and 12 months post roll out.

Is an increase of MRSA in Oslo, Norway, associated with changed infection control policy?
Andersen B.M., Rasch M.,Syversen G. Journal of Infection 2007;55(6):531-8.
During 1993-2006, 358 MRSA cases were registered in Oslo; 43.9% detected in Ullevål University Hospital, 21.2% in nursing homes, and 18.7% in primary healthcare. One out of three (30.4%) were import-associated, and one out of 10 (11.2%) were healthcare personnel. From 2004 on, a new National MRSA Control Guideline was introduced in primary healthcare, served by the community infection control. From 2004 on, there was a 4-6-fold increase of MRSA in primary healthcare and nursing homes. Increase of MRSA cases at Ullevål was import-associated or from outbreaks in primary healthcare. There was no increase of internal spread in the hospital. These data indicate that perhaps a less strict national MRSA infection control guideline in Norway may be associated with the 4-6-fold increase of MRSA cases in the community after 2003.

Resistance of surface-dried virus to common disinfection procedures.
Terpstra F.G., van den Blink A.E., Bos L.M., et al. Journal of Hospital Infection 2007;66:332-8.
0.1 N NaOH and 0.1% hypochlorite were studied for their capacity to inactivate surface-dried lipid-enveloped (LE) [human immunodeficiency virus (HIV), bovine viral diarrhoea virus (BVDV) and pseudorabies virus (PRV)] and non-lipid-enveloped [NLE; canine parvovirus (CPV) and hepatitis A virus (HAV)] viruses in a background of either plasma or culturemedium. In addition, 80% ethanol was tested on surface-dried LE viruses. Without treatment, surface-dried LE viruses remained infectious for at least one week and NLE viruses for more than one month. Irrespective of the disinfectant, inactivation decreased for viruses dried in plasma, which is more representative of viral contaminated blood. Inactivation by all disinfectants improved when preceded by rehydration, although infectivity of CPV actually increased after rehydration.

Rapid recontamination with MRSA of the environment of an intensive care unit after decontamination with hydrogen peroxide vapour.
Hardy K.J., Gossain S., Henderson N., et al. Journal of Hospital Infection 2007;66:360-8.
MRSA was isolated from 11.2% of environmental sites in 3 months preceding use of HPV and revealed that the types circulating within the environment were similar to those colonising patients. After patient discharge and terminal cleaning using conventional methods, MRSA was isolated from 5 sites (17.2%). After HPV decontamination but before the readmission of patients, MRSA was not isolated from the environment. Twenty-four hours after readmitting patients, including 2 colonized with MRSA, the organism was isolated from 5 sites. The strains were indistinguishable from a strain with which a patient was colonized but were not all confined to the immediate vicinity of the patient. In the following 8 weeks, the environment was sampled weekly and MRSA was isolated from 16.3% of sites

Reduction of Clostridium Difficile and vancomycin-resistant Enterococcus contamination of environmental surfaces after an intervention to improve cleaning methods.
Eckstein B.C., Adams D.A., Eckstein E.C., et al. BMC Infectious Diseases 2007;7:61.
During a 6-week period, commonly touched surfaces (ie bedrails, telephones, call buttons, door knobs, toilet seats, and bedside tables) in rooms of patients with CDAD and VRE colonization or infection were monitored before and after housekeeping cleaning, and again after disinfection with 10% bleach by research staff. Of 17 rooms of patients with VRE, 16 (94%) had 1or more +ve environmental cultures before cleaning versus 12 (71%) after cleaning, whereas none had +ve cultures after bleach disinfection by the research staff. Of 9 rooms of patients with CDAD, 100% had positive cultures prior to cleaning vs. 7 (78%) after cleaning (p = 0.50), whereas only 1 (11%) had +ve cultures after bleach disinfection by research staff. After an educational intervention, contamination rates after housekeeping cleaning were significantly reduced.

The development of a new three-step protocol to determine the efficacy of disinfectant wipes on surfaces contaminated with Staphylococcus aureus.
Williams G.J., Denyer S.P., Hosein I.K., Hill D.W., Maillard J.-Y. Journal of Hospital Infection2007;67:329-35.
This paper describes a three-step protocol to quantify the efficacy of disinfectant wipes, their ability to remove and prevent transfer of MRSA and MSSA from inoculated stainless steel surfaces. Test wipes achieved a significantly higher bacterial cell removal than control wipes on all surfaces (p<0.05). The low bactericidal activity of the wipes (<1 log10 reduction when directly inoculated) and the subsequent survival of bacteria on the wipes, however, led to repeated transfer of contamination.

Resistance of surface-dried virus to common disinfection procedures.
Terpstra F.G., van den Blink A.E., Bos L.M., et al. Journal of Hospital Infection 2007;66;332-8.
This study evaluated 0.1 N NaOH and 0.1% hypochlorite for their capacity to inactivate surface-dried lipid-enveloped (LE) HIV, bovine viral diarrhoea virus and pseudorabies virus and non-lipid-enveloped; canine parvovirus and hepatitis A virus in a background of either plasma or culture medium. In addition, 80% ethanol was tested on surface-dried LE viruses. Without treatment, surface-dried LE viruses remained infectious for at least one week and NLE viruses for more than one month. Inactivation decreased for viruses dried in plasma, than virus in culture medium. Inactivation by all disinfectants improved when preceded by rehydration, although the infectivity of CPV actually increased after rehydration.

Chlorine inactivation of highly pathogenic avian influenza virus.
Rice E.W., Adcock N.J., Sivaganesan M., Brown J.D., Stallknecht D.E., Swayne D.E. Emerging Infectious Diseases 2007;13 .
To determine resistance of highly pathogenic avian influenza (H5N1) virus to chlorination, allantoic fluid containing 2 virus strains was exposed to chlorinated buffer at pH 7 and 8, at 5 C. Free chlorine concentrations typically used in drinking water treatment are sufficient to inactivate the virus by >3 orders of magnitude.

Antimicrobial activity and effectiveness of a combination of sodium hypochlorite and hydrogen peroxide in killing and removing Pseudomonas aeruginosa biofilms from surfaces.
DeQueiroz G.A., Day D.F. Journal of Applied Microbiology 2007;103:794-802.
The aim of the study was to evaluate both the antimicrobial activity and the effectiveness of a combination of sodium hypochlorite and hydrogen peroxide (Ox-B) for killing Pseudomonas aeruginosa ATCC 19142 cells and removing P. aeruginosa biofilms on aluminum or stainless steel surfaces. A combination of sodium hypochlorite and hydrogen peroxide effectively killed P. aeruginosa cells and removed biofilms from both stainless steel and aluminium surfaces.

Behaviour of Campylobacter jejuni in experimentally contaminated bottled natural mineral water.
Tatchou-Nyamsi-Konig J.-A., Moreau A., Fedérighi M., Block J.-C. Journal of Applied Microbiology 2007;103:280-8.
This study highlights the fact that, in the event of dual contamination of a bottled natural mineral water (Campylobacter and biodegradable organic matter), the pathogen could survive (and even grow) for a relatively long time, especially at low temperature and in spite of the presence of oxygen. The study showed that survival of Camp. jejuni in natural mineral water was better at 4 C than at 25 C, and the presence of organic matter led to a deceleration in the loss of cultivability and to the multiplication of Camp. jejuni in natural mineral water.

A conceptual model of people’s approach to sanitation.
Avvannavar S.M., Mani M. Science of the Total Environment 2008;390(1):1-12.
The objective of this paper is to trace the various approaches that diverse societies/civilizations, across the world have had towards sanitation, and present a structure to articulate and understand determining factors. The structure presented and discussed in this paper would be useful in understanding a community better in terms of providing appropriate sanitation. It is hoped that this structure be considered as a basis for further refinement and detailed research into each of the factors determining people’s sanitation approach.

Evaluation of liquid and fog application of Sterilox(R) hypochlorous acid solution (HOCl) for surface inactivation of human norovirus.
Park G.W., Boston D.M., Kase J.A., Sampson M.N., Sobsey M.D. Applied Environmental Microbiology 2007;May 4 [Epub ahead of print].
The study were to evaluated the efficacy of hypochlorous acid (HOCl) solution (HAS) against norovirus (NV). Exposing virus-contaminated carriers of ceramic tile (porous) and stainless steel (non-porous) to 200-20 ppm of HOCl solution resulted in >/=99.9 % (>/=3 log10) reductions of both infectivity and RNA titer within 10 min. HOCl fogged in a confined space reduced the infectivity and RNA titers of NV, MNV-1 and MS2 on these carriers by at least 99.9% (3 log10).

Integrating disease control strategies: balancing water sanitation and hygiene interventions to reduce diarrheal disease burden.
Jeisenberg J.N.S., Scott J.C.S., Porco T. American Journal of Public Health 2007;97:846-52.
The paper describes a modeling framework designed to capture the interdependent transmission pathways of enteric pathogens. Results suggest that the benefits of a water quality intervention depend on sanitation and hygiene conditions. When sanitation conditions are poor, water quality improvements may have minimal impact regardless of amount of water contamination. If each transmission pathway alone is sufficient to maintain diarrheal disease, single-pathway interventions will have minimal benefit. Ultimately an intervention will be successful only if all sufficient pathways are eliminated.

Microbial inactivation by microwave radiation in the home environment.
Park D.K ., Bitton G ., Melker R . Journal of Environmental Health 2006;69:17-24.
Kitchen sponges and scrubbing pads were contaminated with wastewater and exposed to microwave radiation. At 100% power level, the total bacterial count of the wastewater was reduced by more that 99% within 1-2 mins, and the total coliform and E. coli were totally inactivated after 30 sec. Bacterial phage MS2 was totally inactivated within 1-2 min. B. cereus spores were more resistant but were eradicated after 4 min. Similar inactivation rates were obtained in wastewater-contaminated scrubbing pads.

Diarrhea prevention in a Kenyan school through the use of a simple safe water and hygiene intervention.
Migele J., Ombeki S., Ayalo M., Biggerstaff M., Quick R. American Journal of Tropical Medicine and Hygiene 2007;76:351-3.
The Safe Water System (water treatment with bleach, safe storage, and behavior-change communications) was implemented to prevent diarrhea in rural Western Kenya . Clinic visits for diarrhea peaked during the January through March period in 2002 at 130 and in 2003 at 71, but in 2004, after project implementation, only 13 diarrhea episodes were recorded. The project saved the school about $5.49 per student per year. The project has been expanded to 70 schools, and an evaluation is planned.

Behavioral indicators of household decision-making and demand for sanitation and potential gains from social marketing in Ghana.
Jenkins M.W., Scott B. Social Science & Medicine 2007; 64(12):2427-42
This paper develops a behavioral approach to assess household demand for improved sanitation in Ghana . Adoption decision stages of preference, intention, and choice to install a toilet are defined, measured, and used to estimate sanitation demand, identify factors affecting demand at each stage, and classify households by adoption stage to identify targeted demand-stimulation strategies. Results from a sample of 536 households indicate that of 74% of households without any home sanitation, 31% have some likelihood of installing a toilet within the next year, but only 6% are very likely to do so; 62% had not considered the idea. Motivating and constraining factors are compared at each adoption stage and strategies likely to increase toilet installation in Ghana are discussed.

Assessment of benefits from use of antimicrobial hand products: reduction in risk from handling ground beef.
Haas C.N., Marie J.R., Rose J.B., Gerba C.P. International Journal of Hygiene and Environmental Health 2005;208:461-6.
Quantitative microbial risk assessment (QMRA) has been used to estimate the benefits resulting from the use of hand cleansing products (e.g., soaps and alcohol- based hand sanitizers etc). This was done by developing a model for the scenario of hand contact with ground beef contaminated with E. coli during food preparation, considering transference of bacteria to the hands, removal and inactivation by hand hygiene, and subsequent transference from the hands to the mouth.

Strategies to reduce person-to-person transmission during widespread Escherichia coli O157:H7 outbreak .
Seto E.Y.W., Soller J.A., Colford J.M. Emerging Infectious Diseases 2007;13:861 -866
Using data from the 2006 E. coli O157:H7 outbreak in 2006 in the United States associated with contaminated spinach, Seto et al developed a model to study secondary person-to-person transmission which showed that secondary transmission was similar to that in previous E. coli outbreaks (˜12%). The model suggests that even a modestly effective hygiene promotion strategy to interrupt secondary transmission (prevention of only 2-3% of secondary illnesses) could result in a reduction of ˜5-11% of symptomatic cases.

Use of hypochlorite solution to decrease rates of Clostridium difficile-associated diarrhea.
McMullen K.M., Zack J., Coopersmith C.M., Kollef M., Dubberke E., Warren D.K. Infection Control and Hospital Epidemiology 2007;28:205-7 [Epub 2007, Jan 26].
An increased rate of Clostridium difficile-associated diarrhea (CDAD) was noted in two intensive care units of a university-affiliated tertiary care facility. One unit instituted enhanced environmental cleaning with a hypochlorite solution in all rooms, whereas the other unit used hypochlorite solution only in rooms of patients with CDAD. The CDAD rates decreased in both units.

Effect of intensive handwashing in the prevention of diarrhoeal illness among patients with AIDS: a randomized controlled study.
Huang D.B., Zhou J. Journal of Medical Microbiology 2007;56:659-63.
Seventy-five patients were randomly assigned to an intensive handwashing intervention (after defecation, after cleaning infants who had defecated, before preparing food, before eating, and before and after sex) and 73 patients were assigned to the control group. Patients assigned to the intensive handwashing intervention group washed their hands more frequently compared with the control group (7 vs. > 4 times a day, respectively; P<0.05) and developed fewer episodes of diarrhoeal illness (1.24+/-0.9 vs. 2.92+/-0.6 new episodes of diarrhoea, respectively; P<0.001) during the 1-year observation.

Designing a protocol that eliminates Clostridium difficile: a collaborative venture.
Whitaker J., Brown S., Vidal S., Calcaterra M. American Journal of Infection Control 2007;35:310-4.
A case-only study was conducted over a 24-month period. Interventions used to reduce the incidence of healthcare-associated Clostridium difficile (C. difficile) included 10% hypochlorite disinfection, soap and water hand hygiene, contact isolation for suspected and confirmed cases, educational tool for patients and visitors, daily isolation rounds, automated report functions, and standardized nursing unit isolation processes. A 66% reduction in the number of healthcare-associated C. difficile cases was achieved during the study.

Reduction of Clostridium difficile and vancomycin-resistant Enterococcus contamination of environmental surfaces after an intervention to improve cleaning methods.
Dubberke E.R., Reske K.A., Noble-Wang J., Thompson A., Killgore G., Mayfield J., Camins B., Woeltje K., McDonald J.R., McDonald L.C., Fraser V.J. American Journal of Infection Control 2007;35:315-8.
During a 6-week period commonly touched surfaces (i.e. bedrails, telephones, call buttons, door knobs, toilet seats, and bedside tables) were cultured in rooms of patients with CDAD and vancomycin-resistant Enterococcus (VRE) colonization or infection before and after housekeeping cleaning, and again after disinfection with 10% bleach. Of the 17 rooms of patients with VRE colonization or infection, 16 (94%) had one or more positive environmental cultures before cleaning versus 12 (71%) after housekeeping cleaning, whereas none had positive cultures after bleach disinfection by the research staff. Of the nine rooms of patients with CDAD, 100% had positive cultures prior to cleaning versus seven (78%) after housekeeping cleaning, whereas only one (11%) had positive cultures after bleach disinfection. After an educational intervention, rates of environmental contamination after housekeeping cleaning were significantly reduced.

Faecal contamination of drinking water sources of Dhaka city during the 2004 flood in Bangladesh and use of disinfectants for water treatment.
Islam M.S., Brooks A., Kabir M.S., Jahid I.K., Shafiqul Islam M., Goswami D., Nair G.B., Larson C., Yukiko W., Luby S. Journal of Applied Microbiology 2007;103:80-7.
During 2004/2005 a total of 300 water samples were collected from 20 different drinking water sources in Kamalapur, Dhaka city. The unacceptable level of contamination of total coliforms (TC), faecal coliforms (FC) and faecal streptococci (FS) ranged from 23.8% to 95.2%, 28.6% to 9.2% and 33.3% to 90.0%, respectively. The isolation rates of V. cholerae O1 and O139 were both 0.33%, and non-O1/non-O139 was 7.0%. Although alum potash, bleaching powder, Halotab and Zeoline ® -200 were all effective general disinfectants, Halotab and Zeoline ® -200 were superior to bleaching powder and alum potash against FC. The study showed that during and after floods, point of use water treatment could reduce waterborne diseases among flood-affected people.

The impact of a school-based safe water and hygiene programme on knowledge and practices of students and their parents: Nyanza Province, western Kenya, 2006.
O'Reilly C.E, Freeman M.C., Ravani M., Migele J., Mwaki A., Ayalo M., Ombeki S., Hoekstra R.M., Quick R. Epidemiology and infection 2007;1-12
A school-based safe water and hygiene intervention was carried out in 45 rural primary schools in Nyanza Province , western Kenya . A CDC team surveyed 390 students from nine schools and their parents at baseline and conducted a final evaluation of 363 students and their parents. From baseline to final evaluation, improvement was seen in students' knowledge of correct water treatment procedure (21-65%) and knowing when to wash their hands. At final evaluation, 14% of parents reported currently treating their water, compared with 6% at baseline (P<0.01). From 2004-2005, school absenteeism in the September-November term decreased in nine project schools by 35% and increased in nine neighbouring comparison schools by 5%.

Efficacy of hospital cleaning agents and germicides against epidemic Clostridium difficile strains.
Fawley W.N., Underwood S., Jane Freeman J., Baines S.D., Saxton K., Stephenson K., Owens R.C., Jr., Wilcox M.H. Infection Control and Hospital Epidemiology 2007;28: in press.
The study used in vitro methods to compare the effects of five cleaning agents and/or germicides (three containing chlorine, one containing only detergent, and one containing hydrogen peroxide) on vegetative and spore forms of Clostridium difficile ( C. difficile). A human fecal emulsion was used to mimic conditions found in situ. When used at recommended concentrations, only chlorine-based germicides inactivated spores. C. difficile epidemic strains had a greater sporulation rate than non-epidemic strains. The mean sporulation rate was 13% for strains not exposed to cleaning agent/germicide, and was significantly increased by exposure to cleaning agents or germicides containing detergent alone (34%), combined detergent and hypochlorite (24%), or hydrogen peroxide (33%). By contrast, the sporulation rate did not change substantially after exposure to germicides containing either both combined detergent and dichloroisocyanurate (9%) or dichloroisocyanurate alone (15%).

The Efficacy of Disinfectants against Staphylococcus aureus ITU Isolates including Methicillin-Resistant S. aureus.
Williams G.J.,Denyer S.P., Hosein I.K., Jenkins D.E., Maillard J.-Y. J Hospital Infection, 2006, 64, supplement 1, P6.06.
This study assessed the efficacy of disinfectants against methicillin-sensitive S. aureus (MSSA) and MRSA hospital isolates as determined by minimum inhibitory concentration (MIC) and surface efficacy tests. MIC determinations showed no difference between the susceptibility of the MSSA and MRSA isolates to sodium dichloroisocyanurate (NaDCC). Interestingly, all strains exhibited a high MIC for NaDCC compared with the in use concentration. Carrier tests showed both MSSA and MRSA strains can survive 30 sec exposures to the in-use NaDCC concentration when organic matter is present, whereas 1 min exposures were bactericidal i.e a high MIC for NaDCC against MSSA and MRSA strains did not predict a failure to kill the target organisms under dirty conditions.

Susceptibility of Germinating Clostridium difficile Spores to 70% Ethanol.
Wheeldon L.J., Worthington T., Hilton A.C. , Lambert P.A., Elliott T.S.J. Journal of Hospital Infection 2006, 64, supplement 1, P9.01.
A carrier test system was designed comprising germination of C. difficile spores for 30 minutes followed by exposure to 70% (v/v) ethanol. A 2-log reduction in germinating C. difficile spores was achieved within 60 minutes. These preliminary results suggest that germination of C. difficile spores increases their susceptibility to 70% ethanol The authors suggest that a two-stage cleaning process comprising germination followed by disinfection may offer an alternative approach to reducing C. difficile spores.

Efficacy of solar disinfection of Escherichia coli , Shigella flexneri , Salmonella Typhimurium and Vibrio cholerae .
Berney M., Weilenmann H.-U., Simonetti A. and Egli T. Journal of Applied Microbiology 2006, 101 828-836.
Resistance to sunlight at 37°C based on F 99 values was in the following order: Salmonella Typhimurium > Escherichia coli > Shigella flexneri > Vibrio cholerae . The applicability of the reciprocity law indicates that fluence rate plays a secondary role in SODIS efficacy. Stating inactivation efficacy with T 90 or F 90 values without showing original data is inadequate for SODIS studies.

The use of microbiocides in infection control: a critical look at safety, testing and applications.
Sattar S.A. Journal of Applied Microbiology 2006 ; 101 743-753 .
This paper is a critical review of the issues related testing and registering of microbiocides meant for use on environmental surfaces and medical devices. It highlights better ways to test microbiocides and to attain global harmonization of testing and product registration. It also details the known and potential dangers of microbiocide use and what to consider in choosing such formulations for optimal safety and effectiveness.

Preventing Healthcare Associated Infections: The Role of Chlorine Products in Risk Reduction.
Soule B.M. A publication of the water quality and health council to the chlorine chemistry Council.
This paper reviews the role of chlorine disinfectants in preventing the transmission of healthcare associated infections via surfaces and via water .