Compliance with face mask use during the COVID-19 pandemic: a community observational study in Singapore.

Introduction: Widespread mask use is an important intervention for control of the coronavirus disease 2019 pandemic. However, data on the factors affecting mask use are lacking. In this observational study, we evaluated the proportion of and factors influencing face mask use and related hygiene practices. Methods: We observed randomly selected members from the public in 367 venues across Singapore, and recorded the proportion of individuals with full compliance with mask use and mask hygiene (hand hygiene before and after touching the mask or face). Logistic regression analyses were used to determine variables associated with mask and hand hygiene compliance. Results: We made 3,821 observations - 2,149 (56.2%) females, 3,569 (93.4%) adults (≥21 years), 212 (5.5%) children (6-20 years) and 40 (1.0%) children (2-5 years). The overall full compliance rate (correct mask use), poor compliance rate (incorrect mask use) and absent mask use were 84.5%, 12.9% and 2.6%, respectively. The factors - male gender, fabric mask usage and crowded indoor venues - were associated with lower mask compliance. Face or mask touching behaviour was observed in 10.7% and 13.7% of individuals observed, respectively. Only one individual performed hand hygiene before and after touching the mask. Conclusion: The rate of mask compliance was high, probably due to legislation mandating mask usage. However, specific factors and crowded indoor venues associated with lower mask compliance were identified. We also noted an issue with the absence of hand hygiene before and after face or mask touching. These issues may benefit from targeted public health messaging.

Nanobiotics against antimicrobial resistance: harnessing the power of nanoscale materials and technologies.

Given the spasmodic increment in antimicrobial resistance (AMR), world is on the verge of "post-antibiotic era". It is anticipated that current SARS-CoV2 pandemic would worsen the situation in future, mainly due to the lack of new/next generation of antimicrobials. In this context, nanoscale materials with antimicrobial potential have a great promise to treat deadly pathogens. These functional materials are uniquely positioned to effectively interfere with the bacterial systems and augment biofilm penetration. Most importantly, the core substance, surface chemistry, shape, and size of nanomaterials define their efficacy while avoiding the development of AMR. Here, we review the mechanisms of AMR and emerging applications of nanoscale functional materials as an excellent substitute for conventional antibiotics. We discuss the potential, promises, challenges and prospects of nanobiotics to combat AMR.

Lack of viable severe acute respiratory coronavirus virus 2 (SARS-CoV-2) among PCR-positive air samples from hospital rooms and community isolation facilities.

BACKGROUND: Understanding the extent of aerosol-based transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is important for tailoring interventions for control of the coronavirus disease 2019 (COVID-19) pandemic. Multiple studies have reported the detection of SARS-CoV-2 nucleic acid in air samples, but only one study has successfully recovered viable virus, although it is limited by its small sample size. OBJECTIVE: We aimed to determine the extent of shedding of viable SARS-CoV-2 in respiratory aerosols from COVID-19 patients. METHODS: In this observational air sampling study, air samples from airborne-infection isolation rooms (AIIRs) and a community isolation facility (CIF) housing COVID-19 patients were collected using a water vapor condensation method into liquid collection media. Samples were tested for presence of SARS-CoV-2 nucleic acid using quantitative real-time polymerase chain reaction (qRT-PCR), and qRT-PCR-positive samples were tested for viability using viral culture. RESULTS: Samples from 6 (50%) of the 12 sampling cycles in hospital rooms were positive for SARS-CoV-2 RNA, including aerosols ranging from <1 µm to >4 µm in diameter. Of 9 samples from the CIF, 1 was positive via qRT-PCR. Viral RNA concentrations ranged from 179 to 2,738 ORF1ab gene copies per cubic meter of air. Virus cultures were negative after 4 blind passages. CONCLUSION: Although SARS-CoV-2 is readily captured in aerosols, virus culture remains challenging despite optimized sampling methodologies to preserve virus viability. Further studies on aerosol-based transmission and control of SARS-CoV-2 are needed.

High Prevalence of 16s rRNA Methylase Genes Among Carbapenem-Resistant Hypervirulent Klebsiella pneumoniae Isolates in a Chinese Tertiary Hospital.

Thirty-nine carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) isolates collected from a Chinese tertiary hospital were used in the characterization of the prevalence of 16S rRNA methylase genes. In total, 66.7% (26/39) of the CR-hvKP isolates were found to carry 16S rRNA methylase genes. The most frequently detected 16S rRNA methylase gene was armA (11/26, 42.3%), followed by rmtB (8/26, 30.8%), and coexistence of both armA and rmtB (7/26, 26.9%). All the clinical isolates were found to carry at least one carbapenemase gene, with blaKPC-2 (79.5%, 31/39), blaNDM-1 (10.3%, 4/39), and cocarrying blaKPC-2 and blaNDM-1 (10.3%, 4/39). A total of 89.7% (35/39) isolates carried extended-spectrum ß-lactamase (ESBL) genes, including 61.5% (24/39) blaSHV-1, 71.8% (28/39) blaTEM-1, and 89.7% (35/39) blaCTX-M-14. All except four isolates (89.7%, 35/39) harbored quinolone resistance genes, with qnrS (82.1%, 32/39), aac(6')-Ib-cr (79.5%, 31/39), and qnrB (2.6%, 1/39). Twenty-six hvKP strains in this study were first reported to cocarry carbapenemase genes, ESBL genes, quinolone resistance genes, and 16S rRNA methylase genes simultaneously. Multilocus sequence typing (MLST) analysis assigned the 39 CR-hvKP isolates into 4 sequence types (STs), with ST11 encompassing 79.5% of the strains. Pulsed field gel electrophoresis (PFGE) typing showed that strains closely related by MLST clustered in major PFGE clusters, of which cluster A accounts for 31 ST11 isolates. Cumulatively, 16S rRNA methylase genes are highly prevalent in CR-hvKP clinical isolates especially for ST11; it is, therefore, critical to continuously monitor the epidemiology of these 16S rRNA methylase-producing CR-hvKP while simultaneously minimizing potential risks from aminoglycoside-resistant CR-hvKP.

Environmental contamination in a coronavirus disease 2019 (COVID-19) intensive care unit-What is the risk?

BACKGROUND: The risk of environmental contamination by severe acute respiratory coronavirus virus 2 (SARS-CoV-2) in the intensive care unit (ICU) is unclear. We evaluated the extent of environmental contamination in the ICU and correlated this with patient and disease factors, including the impact of different ventilatory modalities. METHODS: In this observational study, surface environmental samples collected from ICU patient rooms and common areas were tested for SARS-CoV-2 by polymerase chain reaction (PCR). Select samples from the common area were tested by cell culture. Clinical data were collected and correlated to the presence of environmental contamination. Results were compared to historical data from a previous study in general wards. RESULTS: In total, 200 samples from 20 patient rooms and 75 samples from common areas and the staff pantry were tested. The results showed that 14 rooms had at least 1 site contaminated, with an overall contamination rate of 14% (28 of 200 samples). Environmental contamination was not associated with day of illness, ventilatory mode, aerosol-generating procedures, or viral load. The frequency of environmental contamination was lower in the ICU than in general ward rooms. Eight samples from the common area were positive, though all were negative on cell culture. CONCLUSION: Environmental contamination in the ICU was lower than in the general wards. The use of mechanical ventilation or high-flow nasal oxygen was not associated with greater surface contamination, supporting their use and safety from an infection control perspective. Transmission risk via environmental surfaces in the ICUs is likely to be low. Nonetheless, infection control practices should be strictly reinforced, and transmission risk via droplet or airborne spread remains.

Detection of air and surface contamination by SARS-CoV-2 in hospital rooms of infected patients.

Understanding the particle size distribution in the air and patterns of environmental contamination of SARS-CoV-2 is essential for infection prevention policies. Here we screen surface and air samples from hospital rooms of COVID-19 patients for SARS-CoV-2 RNA. Environmental sampling is conducted in three airborne infection isolation rooms (AIIRs) in the ICU and 27 AIIRs in the general ward. 245 surface samples are collected. 56.7% of rooms have at least one environmental surface contaminated. High touch surface contamination is shown in ten (66.7%) out of 15 patients in the first week of illness, and three (20%) beyond the first week of illness (p = 0.01, χ2 test). Air sampling is performed in three of the 27 AIIRs in the general ward, and detects SARS-CoV-2 PCR-positive particles of sizes >4 µm and 1-4 µm in two rooms, despite these rooms having 12 air changes per hour. This warrants further study of the airborne transmission potential of SARS-CoV-2.

Epidemiologic Features and Clinical Course of Patients Infected With SARS-CoV-2 in Singapore.

Importance: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China, in December 2019 and has spread globally with sustained human-to-human transmission outside China. Objective: To report the initial experience in Singapore with the epidemiologic investigation of this outbreak, clinical features, and management. Design, Setting, and Participants: Descriptive case series of the first 18 patients diagnosed with polymerase chain reaction (PCR)-confirmed SARS-CoV-2 infection at 4 hospitals in Singapore from January 23 to February 3, 2020; final follow-up date was February 25, 2020. Exposures: Confirmed SARS-CoV-2 infection. Main Outcomes and Measures: Clinical, laboratory, and radiologic data were collected, including PCR cycle threshold values from nasopharyngeal swabs and viral shedding in blood, urine, and stool. Clinical course was summarized, including requirement for supplemental oxygen and intensive care and use of empirical treatment with lopinavir-ritonavir. Results: Among the 18 hospitalized patients with PCR-confirmed SARS-CoV-2 infection (median age, 47 years; 9 [50%] women), clinical presentation was an upper respiratory tract infection in 12 (67%), and viral shedding from the nasopharynx was prolonged for 7 days or longer among 15 (83%). Six individuals (33%) required supplemental oxygen; of these, 2 required intensive care. There were no deaths. Virus was detectable in the stool (4/8 [50%]) and blood (1/12 [8%]) by PCR but not in urine. Five individuals requiring supplemental oxygen were treated with lopinavir-ritonavir. For 3 of the 5 patients, fever resolved and supplemental oxygen requirement was reduced within 3 days, whereas 2 deteriorated with progressive respiratory failure. Four of the 5 patients treated with lopinavir-ritonavir developed nausea, vomiting, and/or diarrhea, and 3 developed abnormal liver function test results. Conclusions and Relevance: Among the first 18 patients diagnosed with SARS-CoV-2 infection in Singapore, clinical presentation was frequently a mild respiratory tract infection. Some patients required supplemental oxygen and had variable clinical outcomes following treatment with an antiretroviral agent.

Severe Pediatric Adenovirus 7 Disease in Singapore Linked to Recent Outbreaks across Asia.

During November 2012-July 2013, a marked increase of adenovirus type 7 (Ad7) infections associated with severe disease was documented among pediatric patients in Singapore. Phylogenetic analysis revealed close genetic links with severe Ad7 outbreaks in China, Taiwan, and other parts of Asia.

Reducing hypersensitivity reactions with HLA-B*5701 genotyping before abacavir prescription: clinically useful but is it cost-effective in Singapore?

AIM: Abacavir (ABC) is one of the more affordable antiretroviral drugs used for controlling HIV. Although with similar efficacy to current first-line drugs, its limited usage in Singapore can be attributed to its possible side effect of adverse hypersensitivity reactions (HSRs). HLA-B*5701 genotyping is a clinically relevant procedure for avoiding abacavir-induced HSRs. As patients who do not carry the risk allele are unlikely to develop HSRs, a simple rule can be developed to allow abacavir prescription for patients who are B*5701 negative. Here, we carry out a cost-effectiveness analysis of HLA-B*5701 genotyping before abacavir prescription in the context of the Singapore healthcare system, which caters predominantly to Han Chinese, Southeast-asian Malays, and South-asian Indians. In addition, we aim to identify the most cost-effective treatment regimen for HIV patients. METHODS: A decision tree model was developed in TreeAge. The model considers medical treatment and genotyping costs, genotyping test characteristics, the prevalence of the risk allele, reduction in the quality of life, and increased expenditure due to side effects and other factors, evaluating independently over early-stage and late-stage HIV patients segmented by drug contraindications. RESULTS: The study indicates that genotyping is not cost-effective for any ethnicity irrespective of the disease stage, except for Indian patients with early-stage HIV who are contraindicated to tenofovir. CONCLUSION: Abacavir (as first-line) without genotyping is the cheapest and most cost-effective treatment for all ethnicities except for early-stage Indian HIV patients contraindicated to tenofovir. The HLA-B*5701 frequency, the mortality rate from abacavir-induced HSRs, and genotyping costs are among the major factors influencing the cost-effectiveness.