Hydroxychloroquine for pre-exposure prophylaxis of COVID-19 in health care workers: a randomized, multicenter, placebo-controlled trial Healthcare Worker Exposure Response and Outcomes of Hydroxychloroquine (HERO-HCQ).

OBJECTIVES: To determine whether hydroxychloroquine (HCQ) is safe and effective at preventing COVID-19 infections among health care workers (HCWs). METHODS: In a 1: 1 randomized, placebo-controlled, double-blind, parallel-group, superiority trial at 34 US clinical centers, 1360 HCWs at risk for COVID-19 infection were enrolled between April and November 2020. Participants were randomized to HCQ or matched placebo. The HCQ dosing included a loading dose of HCQ 600 mg twice on day 1, followed by 400 mg daily for 29 days. The primary outcome was a composite of confirmed or suspected COVID-19 clinical infection by day 30, defined as new-onset fever, cough, or dyspnea and either a positive SARS-CoV-2 polymerase chain reaction test (confirmed) or a lack of confirmatory testing due to local restrictions (suspected). RESULTS: Study enrollment closed before full accrual due to recruitment challenges. The primary end point occurred in 41 (6.0%) participants receiving HCQ and 53 (7.8%) participants receiving placebo. No difference in the proportion of participants experiencing clinical infection (estimated difference of -1.8%, 95% confidence interval -4.6-0.9%, P = 0.20) was identified nor any significant safety issues. CONCLUSION: Oral HCQ taken as prescribed appeared safe among HCWs. No significant clinical benefits were observed. The study was not powered to detect a small but potentially important reduction in infection. TRIAL REGISTRATION: NCT04334148.

The role of informational feedback as a game mechanic on user perceptions, attitudes and the intention to continue using a gamified Health Behaviour Change Support System.

Gamification's widespread application across industries has demonstrated its usefulness as a user engagement strategy. In the healthcare sector, the impact of lifestyle diseases has seen the need for modifying health-related behaviours. Health Behaviour Change Support Systems (HBCSS) enhanced with gamification features seek to help users achieve their health related goals. Adapting the Technology Acceptance Model, the role of informational feedback as a game mechanic in influencing perceptions, attitudes and continued usage intentions towards the gamified HBCSS is assessed. The results show a strong influence of attitude towards informational feedback afforded on the continued use intentions of the user.

Design of the Healthcare Worker Exposure Response and Outcomes (HERO) research platform.

BACKGROUND: The SARS CoV-2 virus has caused one of the deadliest pandemics in recent history, resulting in over 170 million deaths and global economic disruption. There remains an urgent need for clinical trials to test therapies for treatment and prevention. DESIGN: An online research platform was created to support a registry community of healthcare workers (HCWs) to understand their experiences and conduct clinical studies to address their concerns. The first study, HERO-HCQ, was a double-blind, multicenter, randomized, pragmatic trial to evaluate the superiority of hydroxychloroquine (HCQ) vs placebo for pre-exposure prophylaxis (PrEP) of COVID-19 clinical infection in HCWs. Secondary objectives were to assess the efficacy of HCQ in preventing viral shedding of COVID-19 among HCWs and to assess the safety and tolerability of HCQ. METHODS: HCWs joined the Registry and were pre-screened for trial interest and eligibility. Trial participants were randomized 1:1 to receive HCQ or placebo. On-site baseline assessment included a COVID-19 nasopharyngeal PCR and blood serology test. Weekly follow-up was done via an online portal and included screening for symptoms of COVID-19, self-reported testing, adverse events, and quality of life assessments. The on-site visit was repeated at Day 30. DISCUSSION: The HERO research platform offers an approach to rapidly engage, screen, invite and enroll into clinical studies using a novel participant-facing online portal interface and remote data collection, enabling limited onsite procedures for conduct of a pragmatic clinical trial. This platform may be an example for future clinical trials of common conditions to enable more rapid evidence generation.

Spot distribution measurement using a scanning nanoslit.

A scanning and rotating nanoslit is used to measure submicrometer features in focused spot distributions. Using a filtered backprojection technique, a highly accurate reconstruction is demonstrated. Experimental results are confirmed by simulating the scanning slit technique using a physical optics simulation program. Analysis of various error mechanisms is reported, and the reconstruction algorithm is determined to be very resilient. The slit is 125 nm wide and 50 µm long and is fabricated on a 120 nm thick layer of aluminum. The size of the image field is 15 µm, and simulations indicate that 200 nm Rayleigh resolution is possible with an infinitely narrow slit.

Characteristics of a scanning nano-slit image sensor for line-and-space patterns.

A single scanning nano-slit is used to study aerial image characteristics. Finite-difference time-domain simulations reveal that, in the far field of such a slit, the detected image contrast is very high over a large spatial frequency range regardless of the polarization direction. In the near field, the TM polarization shows a decrease in contrast at larger spatial frequencies. Experiments verify this characteristic using a 125 nm wide slit on an aluminum mask at a wavelength of 658 nm. Unlike the light transmission characteristics of a nano-slit, which are greatly influenced by slit width and metal mask thickness, it is shown that image contrast measurement is almost insensitive to small changes in these parameters. It is found that defects on the metal mask play an important role in accurate analysis of the system.