Mechanisms of action of microbicides commonly used in infection prevention and control.

SUMMARYUnderstanding how commonly used chemical microbicides affect pathogenic microorganisms is important for formulation of microbicides. This review focuses on the mechanism(s) of action of chemical microbicides commonly used in infection prevention and control. Contrary to the typical site-specific mode of action of antibiotics, microbicides often act via multiple targets, causing rapid and irreversible damage to microbes.

Efficacy of microbicidal actives and formulations for inactivation of Lassa virus in suspension.

The World Health Organization's R&D Blueprint list of priority diseases for 2022 includes Lassa fever, signifying the need for research and development in emergency contexts. This disease is caused by the arenavirus Lassa virus (LASV). Being an enveloped virus, LASV should be susceptible to a variety of microbicidal actives, although empirical data to support this expectation are needed.

Soap, water, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2): an ancient handwashing strategy for preventing dissemination of a novel virus.

Public Health Agencies worldwide (World Health Organization, United States Centers for Disease Prevention & Control, Chinese Center for Disease Control and Prevention, European Centre for Disease Prevention and Control, etc.) are recommending hand washing with soap and water for preventing the dissemination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. In this review, we have discussed the mechanisms of decontamination by soap and water (involving both removal and inactivation), described the contribution of the various components of formulated soaps to performance as cleansers and to pathogen inactivation, explained why adherence to recommended contact times is critical, evaluated the possible contribution of water temperature to inactivation, discussed the advantages of antimicrobial soaps .

Comparison of the Efficacy of Disinfectant Pre-impregnated Wipes for Decontaminating Stainless Steel Carriers Experimentally Inoculated With Ebola Virus and Vesicular Stomatitis Virus.

The authors evaluated four disinfectant pre-impregnated wipes (DPW) for efficacy against Ebola virus Makona variant (EBOV) and vesicular stomatitis virus (VSV), Indiana serotype. Steel carriers were inoculated with the infectious virus and then were wiped with DPW in the Wiperator instrument per ASTM E2967-15. Following the use of J-Cloth impregnated with medium (negative control wipes) or the use of activated hydrogen peroxide (AHP)-, ethanol-, sodium hypochlorite (NaOCl)-, or single or dual quaternary ammonium compound (QAC)-based DPW, virus recovery from the carriers was assayed by titration assay and by two passages on Vero E6 cells in 6-well plates.

Microbicidal actives with virucidal efficacy against SARS-CoV-2 and other beta- and alpha-coronaviruses and implications for future emerging coronaviruses and other enveloped viruses.

Mitigating the risk of acquiring coronaviruses including SARS-CoV-2 requires awareness of the survival of virus on high-touch environmental surfaces (HITES) and skin, and frequent use of targeted microbicides with demonstrated efficacy. The data on stability of infectious SARS-CoV-2 on surfaces and in suspension have been put into perspective, as these inform the need for hygiene. We evaluated the efficacies of formulated microbicidal actives against alpha- and beta-coronaviruses, including SARS-CoV-2.

Virucidal Action Mechanism of Alcohol and Divalent Cations Against Human Adenovirus.

Hygiene and disinfection practices play an important role at preventing spread of viral infections in household, industrial and clinical settings. Although formulations based on >70% ethanol are virucidal, there is a currently a need to reformulate products with much lower alcohol concentrations. It has been reported that zinc can increase the virucidal activity of alcohols, although the reasons for such potentiation is unclear.

Combating SARS-CoV-2: leveraging microbicidal experiences with other emerging/re-emerging viruses.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Wuhan City, China, late in December 2019 is an example of an emerging zoonotic virus that threatens public health and international travel and commerce. When such a virus emerges, there is often insufficient specific information available on mechanisms of virus dissemination from animal-to-human or from person-to-person, on the level or route of infection transmissibility or of viral release in body secretions/excretions, and on the survival of virus in aerosols or on surfaces. The effectiveness of available virucidal agents and hygiene practices as interventions for disrupting the spread of infection and the associated diseases may not be clear for the emerging virus.

Efficacy of microbicides for inactivation of Ebola-Makona virus on a non-porous surface: a targeted hygiene intervention for reducing virus spread.

Microbicides play critical roles in infection prevention and control of Ebola virus by decontaminating high-touch environmental surfaces (HITES), interrupting the virus-HITES-hands nexus. We evaluated the efficacy of formulations containing different microbicidal actives for inactivating Ebola virus-Makona strain (EBOV/Mak) on stainless-steel carriers per ASTM E2197-11. Formulations of sodium hypochlorite (NaOCl) (0.

Assessing the Contributions of Inactivation, Removal, and Transfer of Ebola Virus and Vesicular Stomatitis Virus by Disinfectant Pre-soaked Wipes.

Disinfectant pre-soaked wipes (DPW) containing activated hydrogen peroxide (AHP) or quaternary ammonium compounds (QAC) were tested using ASTM E2967-15 to determine removal, transfer, and inactivation of Ebola virus Makona variant (EBOV/Mak) and vesicular stomatitis virus (VSV) from contaminated stainless steel prototypic environmental surfaces. The infectious virus-contaminated carriers were subjected to wiping in the Wiperator per the standard. Following the use of negative control (J-Cloth)-, AHP-, or QAC-based wipes, recovery of residual infectious virus was assayed.

A 21st century view of infection control in everyday settings: Moving from the Germ Theory of Disease to the Microbial Theory of Health.

Background: The growing understanding of the importance of a healthy microbiome is challenging traditional thinking that resulted in the general acceptance of the Germ Theory of Disease. We propose a more encompassing Microbial Theory of Health that will have implications for the way that we address our relationship with microbes, including hygiene policy and community-based infection control practices.

Methods: This paper considers theories over the last 30 years that have impacted hygiene policy and consumer practice, from the Germ Theory of Disease and the Hygiene Hypothesis, to the Microbial Theory of Health, including the concept of Bidirectional Hygiene.

Reducing antibiotic prescribing and addressing the global problem of antibiotic resistance by targeted hygiene in the home and everyday life settings: A position paper.

Antimicrobial resistance (AMR) continues to threaten global health. Although global and national AMR action plans are in place, infection prevention and control is primarily discussed in the context of health care facilities with home and everyday life settings barely addressed. As seen with the recent global SARS-CoV-2 pandemic, everyday hygiene measures can play an important role in containing the threat from infectious microorganisms.

A 28 Day Clinical Assessment of a Lactic Acid-containing Antimicrobial Intimate Gel Wash Formulation on Skin Tolerance and Impact on the Vulvar Microbiome.

While intimate feminine hygiene products are widely used as part of daily cleansing routines, little is known about how these products impact the vulvovaginal area and its microbiome stability. This 4 week clinical study assessed tolerance of a novel gel wash containing lactic acid (pH 4.2) for external daily use when used on the external genital area and its effects on skin moisturization, vulvar skin pH, and the vulvar microbiome.

Effectiveness of Dettol Antiseptic Liquid for Inactivation of Ebola Virus in Suspension.

The efficacy of Dettol Antiseptic Liquid (DAL) for inactivating Ebola virus (Makona C07 variant) (EBOV/Mak) within an organic load in suspension was evaluated per ASTM E1052-11. Three DAL lots were evaluated at dilutions of 1:10, 1:20, and 1:40, with contact times of 0.5, 1, 5, and 10 min.

Airborne Pathogens inside Automobiles for Domestic Use: Assessing In-Car Air Decontamination Devices Using Staphylococcus aureus as the Challenge Bacterium.

Family cars represent ∼74% of the yearly global output of motorized vehicles. With a life expectancy of ∼8 decades in many countries, the average person spends >100 min daily inside the confined and often shared space of the car, with exposure to a mix of potentially harmful microbes. Can commercial in-car microbial air decontamination devices mitigate the risk? Three such devices (designated devices 1 to 3) with HEPA filters were tested in the modified passenger cabin (3.

Airborne Infectious Agents and Other Pollutants in Automobiles for Domestic Use: Potential Health Impacts and Approaches to Risk Mitigation.

The world total of passenger cars is expected to go from the current one billion to >2.5 billion by 2050. Cars for domestic use account for ~74% of the world's yearly production of motorized vehicles.

Generic aspects of the airborne spread of human pathogens indoors and emerging air decontamination technologies.

Indoor air can be an important vehicle for a variety of human pathogens. This review provides examples of airborne transmission of infectious agents from experimental and field studies and discusses how airborne pathogens can contaminate other parts of the environment to give rise to secondary vehicles leading air-surface-air nexus with possible transmission to susceptible hosts. The following groups of human pathogens are covered because of their known or potential airborne spread: vegetative bacteria (staphylococci and legionellae), fungi (Aspergillus, Penicillium, and Cladosporium spp and Stachybotrys chartarum), enteric viruses (noro- and rotaviruses), respiratory viruses (influenza and coronaviruses), mycobacteria (tuberculous and nontuberculous), and bacterial spore formers (Clostridium difficile and Bacillus anthracis).

Decontamination of indoor air to reduce the risk of airborne infections: Studies on survival and inactivation of airborne pathogens using an aerobiology chamber.

Background: Although indoor air can spread many pathogens, information on the airborne survival and inactivation of such pathogens remains sparse.

Methods: Staphylococcus aureus and Klebsiella pneumoniae were nebulized separately into an aerobiology chamber (24.0 m).

Impact of environmental conditions on the survival of cryptosporidium and giardia on environmental surfaces.

The objective of this study was to find out the impact of environmental conditions on the survival of intestinal parasites on environmental surfaces commonly implicated in the transmission of these parasites. The study was performed by incubating Cryptosporidium and Giardia (oo)cysts on environmentally relevant surfaces such as brushed stainless steel, formica, ceramic, fabric, and skin. Parallel experiments were conducted using clean and soiled coupons incubated under three temperatures.

The survival of influenza A(H1N1)pdm09 virus on 4 household surfaces.

We investigated the survival of a pandemic strain of influenza A H1N1 on a variety of common household surfaces where multiple samples were taken from 4 types of common household fomite at 7 time points. Results showed that influenza A H1N1sw virus particles remained infectious for 48 hours on a wooden surface, for 24 hours on stainless steel and plastic surfaces, and for 8 hours on a cloth surface, although virus recovery from the cloth may have been suboptimal. Our results suggest that pandemic influenza A H1N1 can survive on common household fomites for extended periods of time, and that good hand hygiene and regular disinfection of commonly touched surfaces should be practiced during the influenza season to help reduce transmission.

ECC-RT-PCR: a new method to determine the viability and infectivity of Giardia cysts.

Background: Giardia sp is a major cause of diarrheal illness worldwide, and millions of people are infected each year. Rapid methods to determine the infectivity and virulence of isolates are critical for the development of intervention strategies to control the transmission of Giardia sp cysts, which occurs through contaminated surfaces, food, and water. However, determining the viability, infectivity, and virulence of Giardia sp cysts using molecular methods is a technical challenge because of the lack of a cell culture model.

Comparison of molecular markers for determining the viability and infectivity of Cryptosporidium oocysts and validation of molecular methods against animal infectivity assay.

Background: Globally, disinfectants are widely used to intervene in the dissemination of Cryptosporidium oocysts. However, extensive investigations of oocyst inactivation by various disinfectants are not feasible due to the limitations imposed by animal infectivity methods. Molecular techniques provide an alternative strategy; however, non-metabolic genes have been used as markers for determining viability/infectivity.

The global war against intestinal parasites--should we use a holistic approach?

Intestinal parasite infections have been known to compromise the quality of human life since prehistoric times. Throughout the ages, human civilizations have fought against parasitism, including intestinal parasites. During the second half of the last century, the focus of disease-combating efforts moved to other imminent public health issues, under the notion that the fight against infectious diseases had been won.

Environmental contamination with rhinovirus and transfer to fingers of healthy individuals by daily life activity.

Rhinovirus infection may be acquired by inoculation of virus on fingertips to conjunctiva or nose (self-inoculation). The virus contaminating the fingertips may come from hand contact with someone with a cold or from virus in mucus on environmental surfaces. This study was designed to assess rhinovirus contamination of surfaces by adults with colds and rhinovirus transfer from surfaces to fingertips during normal daily activities.