Assessment of SARS-CoV-2 surrogate inactivation on surfaces and in air using UV and blue light-based intervention technologies.

The COVID-19 pandemic has created an urgent need to utilize existing and develop new intervention technologies for SARS-CoV-2 inactivation on surfaces and in the air. Ultraviolet (UV) technology has been shown to be an effective antimicrobial intervention. Here a study was conducted to determine the efficacy of commercially available UV and blue light-based devices for inactivating HCoV-229E, a surrogate of SARS-CoV-2. The results indicate that two UV devices designed for surface disinfection, with doses of 8.07 µJ/cm2 for the 254 nm device and 20.61 µJ/cm2 for the 275 nm device, were efficient in inactivating 4.94 logs of surface inoculated HCoV-229E. Additionally, a 222 nm UV device with intended ceiling-based operation was effective in inactivating 1.7 logs of the virus inoculated on surface, with a dose of 6 mJ/cm2. A ceiling-based device designed to emit blue light at 405 nm was found to produce 89% reduction in HCoV-229E inoculated on a surface for a dose of 78 J/cm2. Finally, the UV based 222 nm device was found to produce a 90% reduction in the concentration of airborne HCoV-229E, at a 55 µJ/cm2 dose. These results are indicative of the great potential of using UV based technology for the control of SARS-CoV-2.Implications: An important avenue of arresting COVID-19 and future pandemics caused by infectious pathogens is through environmental disinfection. To this effect, the study presented here evaluates commercially available UV and blue light based antimicrobial devices for their ability to kill the human coronavirus HCoV-229E, a surrogate of SARS-CoV-2, on surfaces and in air. The results indicate that two handheld UV devices produced complete inactivation of surface viral inoculum and a UVC ceiling based device produced 1 log reduction in HCoV-229E in air. These results imply the efficacy of UV technology as an antimicrobial tool, especially for rapid disinfection of indoor air.

Detection of SARS-CoV-2 RNA in selected agricultural and food retail environments in Tehran, Iran.

The SARS-CoV-2 pandemic has and continues to impose a considerable public health burden. Although not likely foodborne, SARS-CoV-2 transmission has been well documented in agricultural and food retail environments in several countries, with transmission primarily thought to be worker-to-worker or through environmental high touch surfaces. However, the prevalence and degree to which SARS-CoV-2 contamination occurs in such settings in Iran has not been well documented. Furthermore, since SARS-CoV-2 has been observed to be shed in the feces of some infected individuals, wastewater has been utilized as a means of surveilling the occurrence of SARS-CoV-2 in some regions. This study aimed to investigate the presence of SARS-CoV-2 RNA along the food production and retail chain, from wastewater and irrigation water to vegetables in field and sold in retail. From September 2020 to January 2021, vegetables from different agricultural areas of Tehran province (n = 35), their irrigated agricultural water (n = 8), treated wastewater mixed into irrigated agricultural water (n = 8), and vegetables collected from markets in Tehran (n = 72) were tested for the presence of SARS-CoV-2 RNA. The vegetable samples were washed with TGBE buffer and concentrated with polyethylene glycol precipitation, while water samples were concentrated by an adsorption-elution method using an electronegative filter. RT-qPCR targeting the SARS-CoV-2 N and RdRp genes was then conducted. SARS-CoV-2 RNA was detected in 51/123 (41.5%) of the samples overall. The presence of SARS-CoV-2 RNA in treated wastewater, irrigation water, field vegetables, and market produce were 75, 37.5, 42.85, and 37.5%, respectively. These results indicate that SARS-CoV-2 RNA is present in food retail and may also suggest that produce can additionally be contaminated with SARS-CoV-2 RNA by agricultural water. This study demonstrates that SARS-CoV-2 RNA was detected in waste and irrigation water, as well as on produce both in field and at retail. However, more evidence is needed to understand if contaminated irrigation water causes SARS-CoV-2 RNA contamination of produce, and if there is a significant public health risk in consuming this produce.

Inactivating SARS-CoV-2 Surrogates on Surfaces Using Engineered Water Nanostructures Incorporated with Nature Derived Antimicrobials.

The continuing cases of COVID-19 due to emerging strains of the SARS-CoV-2 virus underscore the urgent need to develop effective antiviral technologies. A crucial aspect of reducing transmission of the virus is through environmental disinfection. To this end, a nanotechnology-based antimicrobial platform utilizing engineered water nanostructures (EWNS) was utilized to challenge the human coronavirus 229E (HCoV-229E), a surrogate of SARS-CoV-2, on surfaces. The EWNS were synthesized using electrospray and ionization of aqueous solutions of antimicrobials, had a size in the nanoscale, and contained both antimicrobial agents and reactive oxygen species (ROS). Various EWNS were synthesized using single active ingredients (AI) as well as their combinations. The results of EWNS treatment indicate that EWNS produced with a cocktail of hydrogen peroxide, citric acid, lysozyme, nisin, and triethylene glycol was able to inactivate 3.8 logs of HCoV-229E, in 30 s of treatment. The delivered dose of antimicrobials to the surface was measured to be in pico to nanograms. These results indicate the efficacy of EWNS technology as a nano-carrier for delivering a minuscule dose while inactivating HCoV-229E, making this an attractive technology against SARS-CoV-2.

Failure to Detect SARS-CoV-2 RNA in the Air During Active Labor in Mothers Who Recently Tested Positive.

The risk of potential SARS-CoV-2 transmission by infected mothers during labor and delivery has not been investigated in-depth. This work collected air samples close to (respiratory droplets) and more distant from (aerosol generation) unvaccinated patients who had previously tested positive for SARS-CoV-2 during labor within 5 days of a positive test. All but one of the patients wore masks during the delivery, and delivery was carried out in either birthing or negative pressure isolation rooms. Our work failed to detect SARS-CoV-2 RNA in any air samples for all of the six patients who gave birth vaginally, despite validation of the limit of detection of the samplers. In sum, this brief report provides initial evidence that the risk of airborne transmission of SARS-CoV-2 during labor may be mitigated by the use of masks and high ventilation rates common in many modern U.S. medical facilities; however more work is needed to fully evaluate the risk of SARS-CoV-2 transmission during labor and maternal pushing.

Inactivating SARS-CoV-2 Surrogates on Surfaces Using Engineered Water Nanostructures Incorporated with Nature Derived Antimicrobials

The continuing cases of COVID-19 due to emerging strains of the SARS-CoV-2 virus underscore the urgent need to develop effective antiviral technologies. A crucial aspect of reducing transmission of the virus is through environmental disinfection. To this end, a nanotechnology-based antimicrobial platform utilizing engineered water nanostructures (EWNS) was utilized to challenge the human coronavirus 229E (HCoV-229E), a surrogate of SARS-CoV-2, on surfaces. The EWNS were synthesized using electrospray and ionization of aqueous solutions of antimicrobials, had a size in the nanoscale, and contained both antimicrobial agents and reactive oxygen species (ROS). Various EWNS were synthesized using single active ingredients (AI) as well as their combinations. The results of EWNS treatment indicate that EWNS produced with a cocktail of hydrogen peroxide, citric acid, lysozyme, nisin, and triethylene glycol was able to inactivate 3.8 logs of HCoV-229E, in 30 s of treatment. The delivered dose of antimicrobials to the surface was measured to be in pico to nanograms. These results indicate the efficacy of EWNS technology as a nano-carrier for delivering a minuscule dose while inactivating HCoV-229E, making this an attractive technology against SARS-CoV-2.

World Society for Virology first international conference: Tackling global virus epidemics.

This communication summarizes the presentations given at the 1st international conference of the World Society for Virology (WSV) held virtually during 16-18 June 2021, under the theme of tackling global viral epidemics. The purpose of this biennial meeting is to foster international collaborations and address important viral epidemics in different hosts. The first day included two sessions exclusively on SARS-CoV-2 and COVID-19. The other two days included one plenary and three parallel sessions each. Last not least, 16 sessions covered 140 on-demand submitted talks. In total, 270 scientists from 49 countries attended the meeting, including 40 invited keynote speakers.

Metagenomic Next-Generation Sequencing in the Diagnosis of HHV-1 Reactivation in a Critically Ill COVID-19 Patient: A Case Report.

Background: Secondary infections pose tremendous challenges in Coronavirus disease 2019 (COVID-19) treatment and are associated with higher mortality rates. Clinicians face of the challenge of diagnosing viral infections because of low sensitivity of available laboratory tests. Case Presentation: A 66-year-old woman initially manifested fever and shortness of breath. She was diagnosed as critically ill with COVID-19 using quantitative reverse transcription PCR (RT-qPCR) and treated with antiviral therapy, ventilator and extracorporeal membrane oxygenation (ECMO). However, after the condition was relatively stabled for a few days, the patient deteriorated with fever, frequent cough, increased airway secretions, and increased exudative lesions in the lower right lung on chest X-rays, showing the possibility of a newly acquired infection, though sputum bacterial and fungal cultures and smears showed negative results. Using metagenomic next-generation sequencing (mNGS), we identified a reactivation of latent human herpes virus type 1 (HHV-1) in the respiratory tract, blood and gastrointestinal tract, resulting in a worsened clinical course in a critically ill COVID-19 patient on ECMO. Anti-HHV-1 therapy guided by these sequencing results effectively decreased HHV-1 levels, and improved the patient's clinical condition. After 49 days on ECMO and 67 days on the ventilator, the 66-year-old patient recovered and was discharged. Conclusions: This case report demonstrates the potential value of mNGS for evidence-based treatment, and suggests that potential reactivation of latent viruses should be considered in critically ill COVID-19 patients.

Pt-, Rh-, Ru-, and Cu-Single-Wall Carbon Nanotubes Are Exceptional Candidates for Design of Anti-Viral Surfaces: A Theoretical Study.

As SARS-CoV-2 is spreading rapidly around the globe, adopting proper actions for confronting and protecting against this virus is an essential and unmet task. Reactive oxygen species (ROS) promoting molecules such as peroxides are detrimental to many viruses, including coronaviruses. In this paper, metal decorated single-wall carbon nanotubes (SWCNTs) were evaluated for hydrogen peroxide (H2O2) adsorption for potential use for designing viral inactivation surfaces. We employed first-principles methods based on the density functional theory (DFT) to investigate the capture of an individual H2O2 molecule on pristine and metal (Pt, Pd, Ni, Cu, Rh, or Ru) decorated SWCNTs. Although the single H2O2 molecule is weakly physisorbed on pristine SWCNT, a significant improvement on its adsorption energy was found by utilizing metal functionalized SWCNT as the adsorbent. It was revealed that Rh-SWCNT and Ru-SWCNT systems demonstrate outstanding performance for H2O2 adsorption. Furthermore, we discovered through calculations that Pt- and Cu-decorated SWNCT-H2O2 systems show high potential for filters for virus removal and inactivation with a very long shelf-life (2.2 × 1012 and 1.9 × 108 years, respectively). The strong adsorption of metal decorated SWCNTs and the long shelf-life of these nanomaterials suggest they are exceptional candidates for designing personal protection equipment against viruses.

Development of nanoparticle-delivery systems for antiviral agents: A review.

The COVID-19 pandemic has resulted in unprecedented increases in sickness, death, economic disruption, and social disturbances globally. However, the virus (SARS-CoV-2) that caused this pandemic is only one of many viruses threatening public health. Consequently, it is important to have effective means of preventing viral transmission and reducing its devastating effects on human and animal health. Although many antivirals are already available, their efficacy is often limited because of factors such as poor solubility, low permeability, poor bioavailability, un-targeted release, adverse side effects, and antiviral resistance. Many of these problems can be overcome using advanced antiviral delivery systems constructed using nanotechnology principles. These delivery systems consist of antivirals loaded into nanoparticles, which may be fabricated from either synthetic or natural materials. Nevertheless, there is increasing emphasis on the development of antiviral delivery systems from natural substances, such as lipids, phospholipids, surfactants, proteins, and polysaccharides, due to health and environmental issues. The composition, morphology, dimensions, and interfacial characteristics of nanoparticles can be manipulated to improve the handling, stability, and potency of antivirals. This article outlines the major classes of antivirals, summarizes the challenges currently limiting their efficacy, and highlights how nanoparticles can be used to overcome these challenges. Recent studies on the application of antiviral nanoparticle-based delivery systems are reviewed and future directions are described.