Journal: The Journal of hospital infection
Currently, the emergence of a novel human coronavirus, temporary named 2019-nCoV, has become a global health concern causing severe respiratory tract infections in humans. Human-to-human transmissions have been described with incubation times between 2-10 days, facilitating its spread via droplets, contaminated hands or surfaces. We therefore reviewed the literature on all available information about the persistence of human and veterinary coronaviruses on inanimate surfaces as well as inactivation strategies with biocidal agents used for chemical disinfection, e.g. in healthcare facilities. The analysis of 22 studies reveals that human coronaviruses such as Severe Acute Respiratory Syndrome (SARS) coronavirus, Middle East Respiratory Syndrome (MERS) coronavirus or endemic human coronaviruses (HCoV) can persist on inanimate surfaces like metal, glass or plastic for up to 9 days, but can be efficiently inactivated by surface disinfection procedures with 62-71% ethanol, 0.5% hydrogen peroxide or 0.1% sodium hypochlorite within 1 minute. Other biocidal agents such as 0.05-0.2% benzalkonium chloride or 0.02% chlorhexidine digluconate are less effective. As no specific therapies are available for 2019-nCoV, early containment and prevention of further spread will be crucial to stop the ongoing outbreak and to control this novel infectious thread.
Hand hygiene is a fundamental component of infection prevention, but few studies have examined whether hand-drying method affects the risk of dissemination of potential pathogens.
SARS-CoV-2 is the virus responsible for the current global pandemic, COVID-19. Because this virus is novel, little is known about its sensitivity to disinfection. In this study, we performed suspension tests against SARS-CoV-2 using three commercially available quaternary ammonium compound (Quat) disinfectants and one laboratory-made 0.2% benzalkonium chloride solution. Three of the four formulations completely inactivated the virus within 15 seconds of contact, even in the presence of a soil load or when diluted in hard water. We conclude that Quats rapidly inactivate SARS-CoV-2, making them potentially useful for controlling SARS-CoV-2 spread in hospitals and the community.
BACKGROUND: Most surgical masks are not certified for use as respiratory protective devices (RPDs). In the event of an influenza pandemic, logistical and practical implications such as storage and fit testing will restrict the use of RPDs to certain high-risk procedures that are likely to generate large amounts of infectious bioaerosols. Studies have shown that in such circumstances increased numbers of surgical masks are worn, but the protection afforded to the wearer by a surgical mask against infectious aerosols is not well understood. AIM: To develop and apply a method for assessing the protection afforded by surgical masks against a bioaerosol challenge. METHODS: A dummy test head attached to a breathing simulator was used to test the performance of surgical masks against a viral challenge. Several designs of surgical masks commonly used in the UK healthcare sector were evaluated by measuring levels of inert particles and live aerosolised influenza virus in the air, from in front of and behind each mask. FINDINGS: Live influenza virus was measurable from the air behind all surgical masks tested. The data indicate that a surgical mask will reduce exposure to aerosolised infectious influenza virus; reductions ranged from 1.1- to 55-fold (average 6-fold), depending on the design of the mask. CONCLUSION: We describe a workable method to evaluate the protective efficacy of surgical masks and RPDs against a relevant aerosolised biological challenge. The results demonstrated limitations of surgical masks in this context, although they are to some extent protective.
Tight-fitting FFP3 facemasks are ideal respiratory protective equipment during aerosol generating procedures in Covid-19 environment, and require a Fit Test (FT) to assess mask-face seal competency. Facial hair is considered to be an impediment for achieving a competent seal. We are describing an under-mask beard cover called Singh Thattha technique which obtained a pass rate of 25/27 (92.6%) by qualitative and 5/5 (100%) by quantitative FT in full-bearded individuals. Sturdier versions of FFP3 were more effective. Individuals for whom shaving is not possible, the Singh Thattha technique could offer an effective solution to safely don respirator masks.
Ethanol is used worldwide in healthcare facilities for hand rubbing. It has been described to have a stronger and broader virucidal activity compared to propanols. The aim of this review was to describe the spectrum of virucidal activity of ethanol in solution or as commercially available products. A systematic search was conducted. Studies were selected when they contained original data on reduction of viral infectivity from suspension tests (49 studies) and contaminated hands (17 studies). Ethanol at 80% was highly effective against all tested 21 enveloped viruses within 30s. Murine norovirus and adenovirus type 5 are usually inactivated by ethanol between 70% and 90% in 30s whereas poliovirus type 1 was often found to be too resistant except for ethanol at 95% (all test viruses of EN 14476). Ethanol at 80% is unlikely to be sufficiently effective against poliovirus, FCV, polyomavirus, HAV and FMDV. The spectrum of virucidal activity of ethanol at 95%, however, covers the majority of clinically relevant viruses. Additional acids can substantially improve the virucidal activity of ethanol at lower concentrations against e.g. poliovirus, FCV, polyomavirus and FMDV although selected viruses such as HAV may still be too resistant. The selection of a suitable virucidal hand rub should be based on the most common viruses prevalent in a unit and the user acceptability of the product under frequent use conditions.
Multi-drug resistant Gram negative bacteria are of major clinical concern. The increasing prevalence of carbapenemase-producing Enterobacteriaceae (CPE), resistant to all beta-lactams including carbapenems, and able to colonise the large intestine represent a key threat. Rapid, accurate detection of intestinal CPE colonisation is critical to minimise transmission, and hence reduce costly, difficult to treat CPE infections. There is currently no ‘gold standard’ CPE detection method. Following a survey of diagnostic laboratories in England, we report considerable heterogeneity in diagnostic CPE testing methods and procedures.
The efficiency of hand drying is important in preventing pathogen spread, but knowledge surrounding which drying methods contribute least towards contamination of the environment and users is limited.
It is unknown whether healthcare workers' facial hair harbours nosocomial pathogens. We compared facial bacterial colonization rates among 408 male healthcare workers with and without facial hair. Workers with facial hair were less likely to be colonized with Staphylococcus aureus (41.2% vs 52.6%, P = 0.02) and meticillin-resistant coagulase-negative staphylococci (2.0% vs 7.0%, P = 0.01). Colonization rates with Gram-negative organisms were low for all healthcare workers, and Gram-negative colonization rates did not differ by facial hair type. Overall, colonization is similar in male healthcare workers with and without facial hair; however, certain bacterial species were more prevalent in workers without facial hair.
Coronavirus disease 2019 (COVID-19) was first reported in Wuhan in December 2019 and has rapidly spread across different cities within and outside China. Hong Kong started to prepare for COVID-19 on 31st December 2019 and infection control measures in public hospitals were tightened to limit nosocomial transmission within healthcare facilities. However, the recommendations on the transmission-based precautions required for COVID-19 in hospital settings vary from droplet and contact precautions, to contact and airborne precautions with placement of patients in airborne infection isolation rooms.