Abstract. The reuse of N95 masks has been forced on small community-based hospitals, dentists, nursing, and care homes, amongst others, due to the desperate shortage of personal protective equipment globally during the COVID-19 pandemic. The CDC issued guidance on the reuse of N95 masks due to this shortage. However, large scale ultraviolet disinfection equipment would not be practical in these circumstances, we, therefore, investigated the efficacy of a small, mobile, benchtop device with the potential to disinfect N95 masks from SARS-CoV-2 using ultraviolet irradiation. The device tested was the Lumin LM3000 System manufactured by 3B Medical. We found the Lumin LM3000 to be effective against enveloped viruses, including coronavirus, non-enveloped viruses, gram-negative and gram-positive bacteria and spores with reductions greater than 99.9 per centAbstract content goes here
Background: It has long been known that nasal inoculation with influenza A virus produces asymptomatic to febrile infections. Uncertainty persists about whether these infections are sufficiently similar to natural infections for studying human-to-human transmission. Methods: We compared influenza A viral aerosol shedding from volunteers nasally inoculated with A/Wisconsin/2005 (H3N2) and college community adults naturally infected with influenza A/H3N2 (2012-2013), selected for influenza-like illness with objectively measured fever or a positive Quidel QuickVue A&B test. Propensity scores were used to control for differences in symptom presentation observed between experimentally and naturally infected groups. Results: Eleven (28%) experimental and 71 (86%) natural cases shed into fine particle aerosols (p<0.001). The geometric mean (geometric standard deviation) for viral positive fine aerosol samples from experimental and natural cases was 5.1E+3 (4.72) and 3.9E+4 (15.12) RNA copies/half hour, respectively. The 95th percentile shedding rate was 2.4 log10 greater for naturally infected cases (1.4E+07 versus 7.4E+04). Certain influenza-like illness related symptoms were associated with viral aerosol shedding. The almost complete lack of symptom severity distributional overlap between groups did not support propensity score adjusted shedding comparisons. Conclusions: Due to selection bias, the natural and experimental infections had limited symptom severity distributional overlap precluding valid, propensity score adjusted comparison. Relative to the symptomatic naturally infected cases, where high aerosol shedders were found, experimental cases did not produce high aerosol shedders. Studying the frequency of aerosol shedding at the highest observed levels in natural infections without selection on symptoms or fever would support helpful comparisons.
Abstract. The Controlled Human Infection Model and specifically the Human Viral Challenge Model are not dissimilar to standard clinical trials while adding another layer of complexity and safety considerations. The models deliberately infect volunteers, with an infectious challenge agent (CA) to determine the effect of the infection and the potential benefits of the experimental interventions. The Human Viral Challenge Model studies can shorten the time to assess the efficacy of a new vaccine or treatment by combining this with the assessment of safety. The newly emerging SARS-COV-2 virus is highly contagious and the cause pandemic disease COVID-19. An urgent race in is on to develop a new vaccine against this virus in a timeframe never attempted before. The use of the Human Viral Challenge Model has been proposed to accelerate the development of the vaccine. In the early 2000’s the authors successfully developed a pathogenic Human Viral Challenge Model for another virus for which there was no effective treatment and established it to evaluate potential therapies and vaccines against Respiratory Syncytial Virus. The authors feel that the experience gained in the development of that model can help with the development of a COVID-19 HVCM and describe it here. Word count: 197