ABSTRACT
The COVID-19 pandemic refocused scientists the world over to produce technologies that will be able to prevent the spread of such diseases in the future. One area that deservedly receives much attention is the disinfection of health facilities like hospitals, public areas like bathrooms and train stations, and cleaning areas in the food industry. Microorganisms and viruses can attach to and survive on surfaces for a long time in most cases, increasing the risk for infection. One of the most attractive disinfection methods is paints and coatings containing nanoparticles that act as photocatalysts. Of these, titanium dioxide is appealing due to its low cost and photoreactivity. However, on its own, it can only be activated under high-energy UV light due to the high band gap and fast recombination of photogenerated species. The ideal material or coating should be activated under artificial light conditions to impact indoor areas, especially considering wall paints or frequent-touch areas like door handles and elevator buttons. By introducing dopants to TiO2 NPs, the bandgap can be lowered to a state of visible-light photocatalysis occurring. Naturally, many researchers are exploring this property now. This review article highlights the most recent advancements and research on visible-light activation of TiO2-doped NPs in coatings and paints. The progress in fighting air pollution and personal protective equipment is also briefly discussed. Graphical Abstract: Indoor visible-light photocatalytic activation of reactive oxygen species (ROS) over TiO2 nanoparticles in paint to kill bacteria and coat frequently touched surfaces in the medical and food industries.
ABSTRACT
The COVID-19 pandemic refocused scientists the world over to produce technologies that will be able to prevent the spread of such diseases in the future. One area that deservedly receives much attention is the disinfection of health facilities like hospitals, public areas like bathrooms and train stations, and cleaning areas in the food industry. Microorganisms and viruses can attach to and survive on surfaces for a long time in most cases, increasing the risk for infection. One of the most attractive disinfection methods is paints and coatings containing nanoparticles that act as photocatalysts. Of these, titanium dioxide is appealing due to its low cost and photoreactivity. However, on its own, it can only be activated under high-energy UV light due to the high band gap and fast recombination of photogenerated species. The ideal material or coating should be activated under artificial light conditions to impact indoor areas, especially considering wall paints or frequent-touch areas like door handles and elevator buttons. By introducing dopants to TiO2 NPs, the bandgap can be lowered to a state of visible-light photocatalysis occurring. Naturally, many researchers are exploring this property now. This review article highlights the most recent advancements and research on visible-light activation of TiO2-doped NPs in coatings and paints. The progress in fighting air pollution and personal protective equipment is also briefly discussed. Graphical Indoor visible-light photocatalytic activation of reactive oxygen species (ROS) over TiO2 nanoparticles in paint to kill bacteria and coat frequently touched surfaces in the medical and food industries.
ABSTRACT
Background: The pandemic of COVID-19 has led to an upsurge of critically ill patients requiring advanced life support. Bacteria and fungi have been isolated as etiological agents for co-infections among COVID-19 patients in the intensive care unit (ICU). Co-infection has been associated with worse outcomes among COVID-19 patients in ICUs. The aim of this study was to determine the prevalence of co-infections and their antimicrobial susceptibility patterns among COVID-19 patients admitted to intensive care units in Uganda. Materials and Methods: A multi-center cross-sectional retrospective survey was carried out in Intensive Care Units (ICUs) in Mulago national referral hospital, UMC Victoria and TMR international hospital in Uganda. The records of 216 hospitalized ICU COVID-19 patients were purposively sampled using a standardized data abstraction tool. The collected data were double entered in Epi-data version 3.1 and exported to Stata version 17.0 for statistical analysis. Results: The prevalence of co-infections (bacterial and fungal) was 111(51.39%) with respiratory tract infections 57(51.35%) being the most prevalent. Staphylococcus aureus 23(28.75%), Citrobacter freudii 19(23.75%), Pseudomonas aureginosa 15(18.75%) and Klebsiella pneumoniae 10(12.50%) were the most frequently isolated bacterial species. The prevalence of multidrug resistant bacterial species was 75.95%. About 07/8(8.75%) of the bacterial species were extended spectrum beta lactamase or AmpC beta lactamase producers. Some of ESBL producers demonstrated susceptibility to Augmentin, Amikacin and trimethoprim. Augmentin 33/54(61.11%) and ceftriaxone 4/44(9.09%) had the highest and lowest overall antibiotic susceptibility respectively. About 31/111(27.93%) of the organisms were Candida albicans. The fungal species isolated had good overall susceptibility to most commonly used antifungal agents in the study setting. Conclusion: This study found a high prevalence of co-infections (bacterial and fungal). Respiratory tract infection was the most prevalent. There was an overwhelming burden of multidrug resistant infections with some extended spectrum drug resistant organisms isolated among COVID-19 patients admitted in the Ugandan ICUs. There is need for establishment of stronger policy measures in regards to antibiotic stewardship, antimicrobial surveillance and infection control to inform empirical antibiotic therapy and mitigate the spread MDR bacteria and antibiotic drug resistance among COVID-19 patients.
Subject(s)
COVID-19ABSTRACT
BACKGROUND: The COVID-19 pandemic is placing abnormally high and ongoing demands on healthcare systems. Little is known about the full effect of the COVID-19 pandemic on diseases other than COVID-19 in the South African setting. OBJECTIVE: To describe a cohort of hospitalised patients under investigation for SARS-CoV-2 that initially tested negative. METHODS: Consecutive patients hospitalised at Khayelitsha Hospital from April to June 2020, whose initial polymerase chain reaction test for SARS-CoV-2 was negative were included. Patient demographics, clinical characteristics, ICD-10 (International Statistical Classification of Diseases and Related Health Problems 10th Revision) diagnosis, referral to tertiary level facilities and ICU, and all-cause in-hospital mortality were collected. The 90-day re-test rate was determined and comparisons were made using the χ2-test and the independent samples median test. RESULTS: Overall, 261 patients were included: median age 39.8 years, 55.6% female (n = 145). Frequent comorbidities included HIV (41.4%), hypertension (26.4%), and previous or current tuberculosis (24.1%). Nine (3.7%) patients were admitted to ICU and 38 (15.6%) patients died. Ninety-three patients (35.6%) were re-tested and 21 (22.6%) were positive for SARS-CoV-2. The top primary diagnoses related to respiratory diseases (n = 82, 33.6%), and infectious and parasitic diseases (n = 62, 25.4%). Thirty-five (14.3%) had a COVID-19 diagnostic code assigned (26 without microbiological confirmation) and 43 (16.5%) had tuberculosis. Older age (p = 0.001), chronic renal impairment (p = 0.03) and referral to higher level of care (all p < 0.001; ICU p = 0.03) were more frequent in those that died. CONCLUSION: Patients with tuberculosis and other diseases are still presenting to emergency centres with symptoms that may be attributable to SARS-CoV-2 and requiring admission. Extreme vigilance will be necessary to diagnosis and treat tuberculosis and other diseases as we emerge from the COVID-19 pandemic.