A fast point-of-care PCR test for infectious diseases, based on aerosol capturing

The COVID-19 pandemic quickly revealed the limitations of existing monitoring and diagnostic capabilities. While rapid antigen tests are not sufficiently reliable, PCR turn-around-time (TAT) typically ranges from hours to days. Standard swab-based tests are also cumbersome and invasive and, worse yet, they detect infection and not transmissibility. A reliable diagnostic test able to discern the infectious phase of COVID-19 could interrupt transmission while limiting isolation requirements. We developed a non-invasive, impaction-based method for capturing aerosols from human breath in one minute of sampling. A proof-of-principle system was used for the detection of viral RNA in breath samples from confirmed positive subjects (=29). A lab setup demonstrated compatibility with on-chip PCR, reducing the TAT to 15-20 minutes. Positive percentage agreement (PPA) between a breath- and nasopharyngeal PCR is 75% overall and 92% in the first 7 days of infection, after which the breath does not contain measurable virus anymore. Breath positivity corresponds to the infectious window. No false positives were noted. Diagnostic accuracy is superior to nasopharyngeal rapid antigen tests. This novel concept of aerosol capturing combined with ultra-fast PCR is proven to be effective to detect SARS-CoV-2 in breath, rivalling the standard nasopharyngeal PCR tests. Combined with a TAT on par with rapid antigen tests, the technology has the potential to become a standard test in the coming years, for COVID-19 or other infectious diseases. A validation study with an advanced setup is currently ongoing, first data should be available during the presentation.

Correlates of COVID-19 vaccination status among college students.

Objectives: Despite the widespread availability of COVID-19 vaccines in the United States, vaccine hesitancy remains high among certain groups. This study examined the correlates of being unvaccinated among a sample of students attending a single university (N = 2900) during the spring and summer of 2021, when the campus had been closed for over a year and students were preparing to return to in-person learning. Methods: Students responded to an email invitation and completed electronic surveys. Results: In multivariable logistic regression analyses, students were more likely to be unvaccinated if they were African American, identified with any political affiliation other than Democrat, were undergraduates or international students, had not traveled outside the Los Angeles during the pandemic, and/or had previously been ill with COVID-19. Conclusion: Findings indicate that culturally resonant educational interventions, and possibly vaccine requirements, are needed to promote vaccination among university students.

Social media in neurosurgery during COVID-19: an evaluation of the role of Neurosurgery Cocktail platform.

BACKGROUND: Social media use in neurosurgery remains an understudied phenomenon. Our study aims to examine the global membership and engagement of the prominent Neurosurgery Cocktail Facebook group with over 25,000 neurosurgeons and trainees worldwide, specifically during the COVID-19 pandemic. METHODS: Neurosurgery Cocktail's numbers of members, posts, comments, and reactions were collected from December 2019 to November 2020. Anonymized aggregate data of members' characteristics, including age, sex, and country of origin in November 2020, were also obtained. The most engaging posts in November 2020 were categorized into topics by a majority consensus of 3 reviewers. RESULTS: The average number of members steadily increased from 21,266 in December 2019 to 25,218 in November 2020. In November 2020, 18.8% of members were women, and 71.3% were between 25-44 years old. With members from 100 countries, 77.9% are from low-and middle-income countries, with the highest representation from India, Egypt, and Brazil. After the COVID-19 pandemic declaration, daily engagement peaked in April 2020 with a daily average of 41.63 posts, 336.4 comments, and 1,914.6 reactions before returning to prepandemic levels. Among the 99 top posts in November 2020, the majority (56.5%) were classified as "interesting cases", with "education-related" as the second-most common topic (16.2%). CONCLUSIONS: Neurosurgery Cocktail has shown steady growth since its creation. The COVID-19 pandemic was correlated with a spike in activity without lasting impact. The group demonstrates social media's potential for knowledge exchange and promoting organic international collaborations.

COVID-19 booster vaccine attitudes and behaviors among university students and staff in the United States: The USC Trojan pandemic research Initiative.

Although authorized mRNA COVID-19 vaccines (BNT162b2 by BioNTech/Pfizer and mRNA-1273 by Moderna) significantly reduce morbidity and mortality, recent evidence suggests that immunity wanes over time, and that a booster dose could further reduce COVID-19 transmission and severe illness. However, research examining attitudes on booster willingness in diverse populations is needed. This study examined COVID-19 booster vaccine attitudes and behaviors among university students and staff in the fall of 2021. In our sample, 96.2% of respondents indicated willingness to get a COVID-19 booster shot at least once per year. In both bivariate and multivariate analyses higher trust in science was associated with having higher odds of booster willingness. Those who identify as Black, on average, reported trusting science less than other racial/ethnic groups. Our findings demonstrate high willingness to receive a COVID-19 booster shot and highlight the importance of educational messages and initiatives that focus on building trust in science to increase willingness to get the COVID-19 booster. More research is needed to better understand the impact of cultural beliefs on booster willingness and vaccine hesitancy. This understanding will help determine what messages and populations to target to increase booster willingness in the future.

Characteristics associated with COVID-19 vaccination status among staff and faculty of a large, diverse University in Los Angeles: The Trojan Pandemic Response Initiative.

Objective: This study examined characteristics associated with being unvaccinated among a sample of university staff and faculty prior to university campus reopening for in-person learning in 2021. Methods: Staff and faculty responded to an email invitation to complete an online survey. Survey questions included demographic data (race/ethnicity, age, sex), COVID-19 knowledge and behaviors, employment specific data including division and subdivision (healthcare vs. non-healthcare related division); and self-reported vaccination status. A multivariable logistic regression analysis was performed to determine significant characteristics associated with the likelihood of being unvaccinated for COVID-19. Results: Participants identifying as Asian and Asian American (aOR = 1.44, 95% CI: 1.06, 1.96), Hispanic/Latinx (aOR = 1.73, 95% CI: 1.21, 2.49) or Multicultural/Other (aOR = 1.72, 95% CI: 1.24, 2.38) had greater odds of being unvaccinated compared to Non-Hispanic White participants. Other characteristics associated with greater likelihood of being unvaccinated included working as a university staff member (vs. faculty) (aOR = 1.69, 95% CI: 1.24. 2.30), decrease in income (aOR = 1.34, 95% CI:1.05, 1.71), inability to work remotely (aOR = 1.48, 95% CI:1.13, 1.93) and not traveling outside of the Los Angeles area (aOR = 1.46, 95% CI: 1.16, 1.83). Political affiliation as an Independent (aOR = 1.39, 95% CI:1.04, 1.85) or as something else (aOR = 3.84, 95% CI: 2.72, 5.41) were more likely to be unvaccinated compared to participants identifying as Democrat. Conclusions: Several factors associated with racial and social disparities may delay the uptake of COVID-19 vaccination. This study highlights the need for targeted educational interventions to promote vaccination among university staff and faculty.

Correlates of COVID-19 vaccination status among college students (preprint)

ObjectivesDespite the widespread availability of COVID-19 vaccines in the United States, vaccine hesitancy remains high among certain groups. This study examined the correlates of being unvaccinated among a sample of university students (N=2900) during the spring and summer of 2021, when the campus had been closed for over a year and students were preparing to return to in-person learning. MethodsStudents responded to an email invitation and completed electronic surveys. Results. In multivariable logistic regression analyses, students were more likely to be unvaccinated if they were African American, identified with any political affiliation other than Democrat, were undergraduates or international students, had not traveled outside the Los Angeles during the pandemic, and/or had previously been ill with COVID-19. ConclusionFindings indicate that culturally resonant educational interventions, and possibly vaccine requirements, are needed to promote vaccination among university students.

Nano-Enabled COVID-19 Vaccines: Meeting the Challenges of Durable Antibody Plus Cellular Immunity and Immune Escape.

At the time of preparing this Perspective, large-scale vaccination for COVID-19 is in progress, aiming to bring the pandemic under control through vaccine-induced herd immunity. Not only does this vaccination effort represent an unprecedented scientific and technological breakthrough, moving us from the rapid analysis of viral genomes to design, manufacture, clinical trial testing, and use authorization within the time frame of less than a year, but it also highlights rapid progress in the implementation of nanotechnology to assist vaccine development. These advances enable us to deliver nucleic acid and conformation-stabilized subunit vaccines to regional lymph nodes, with the ability to trigger effective humoral and cellular immunity that prevents viral infection or controls disease severity. In addition to a brief description of the design features of unique cationic lipid and virus-mimicking nanoparticles for accomplishing spike protein delivery and presentation by the cognate immune system, we also discuss the importance of adjuvancy and design features to promote cooperative B- and T-cell interactions in lymph node germinal centers, including the use of epitope-based vaccines. Although current vaccine efforts have demonstrated short-term efficacy and vaccine safety, key issues are now vaccine durability and adaptability against viral variants. We present a forward-looking perspective of how vaccine design can be adapted to improve durability of the immune response and vaccine adaptation to overcome immune escape by viral variants. Finally, we consider the impact of nano-enabled approaches in the development of COVID-19 vaccines for improved vaccine design against other infectious agents, including pathogens that may lead to future pandemics.

Étude prospective de séroprévalence du Sars-Cov-2 chez 249 patients suivis pour un rhumatisme inflammatoire chronique

Introduction La prévalence des formes asymptomatiques d’infection COVID-19 en population générale est mal connue à ce jour (<10 %). L’objectif de cette étude était d’évaluer la séroprévalence COVID-19 au sein de patients atteints d’un rhumatisme inflammatoire chronique (PR ou SPA) sous traitement de fond immunomodulateurs et étudier la proportion de formes symptomatiques et asymptomatiques. Patients et méthodes Nous avons effectué un dépistage systématique d’infection à SarS-Cov-2 par sérologie en hospitalisation de jour de rhumatologie de l’hôpital Cochin entre le 1er juin et le 31 août 2020, chez les patients suivis pour une SPA (axiale ou périphérique) ou pour une PR, hospitalisés pour réalisation d’une biothérapie IV ou pour avis thérapeutique. Chaque patient était interrogé sur la survenue de symptômes évocateurs de COVID-19 depuis janvier 2020. Les tests sérologiques étaient réalisés de façon systématique chez les patients pris consécutivement. Le test sérologique utilisé a été validé par la Société française de virologie. Il s’agit d’un test sérologique qualitatif (immuno-essai chimioluminescent microparticulaire, Abbott, USA) qui détecte les IgG dirigés contre la protéine N. Résultats Sur la période d’analyse, 249 patients ont été inclus dont 121 PR et 128 SPA. Les patients SpA avaient un âge moyen de 51 ans (±14) et une durée moyenne d’évolution de 8 ans (±14). La majorité des patients étaient traités par anti-TNF seuls (n=60) ou en association avec leflunomide (n=1), SLZ (n=3), HCQ (n=1) ou MTX (n=57). Un patient était traité par baricitinib et 1 autre par l’association sécukinumab/SLZ. Trois patients étaient en monothérapie par MTX et 1 sous SLZ. Une corticothérapie était associée au traitement de fond dans 7 % des cas (n=9). Les patients PR avaient une durée moyenne d’évolution de 19 ans (±12). Une grande majorité des patients étaient sous biothérapies compte tenu du mode de recrutement (bDMARDs n=101, tsDMARDS n=2, csDMARDS n=18). Ainsi, 18 patients étaient traités par anti-TNF en association avec du MTX (78 %), du leflunomide (16 %) ou de l’imurel (5 %) ;20 sous abatacept seul (40 %) ou en association avec du MTX (45 %) ou du leflunomide (15 %) ;23 sous TOCI seul (48 %) ou associé au MTX (45 %), au leflunomide (10 %) ou à l’imurel (5 %) et 40 sous rituximab seul (25 %) ou associé au MTX (62,5 %), au leflunomide (7,5 %), à l’imurel (2,5 %) à l’HCQ (2,5 %). Une corticothérapie était associée au traitement de fond dans 43 % des cas (n=53). Sur les 249 sérologies réalisées, 7 (2,8 %) étaient positives (4 SpA et 3 PR). L’âge moyen des patients avec séroconversion était de 52 ans (±10). Concernant le traitement, 6 patients étaient traités par anti-TNF seul (n=2) ou en association avec le MTX (n=4) et un patient avait une association RTX+MTX. Une corticothérapie était associée chez 2 patients PR. Parmi les patients avec séroconversion, un seul patient n’a présenté aucun symptôme clinique évoquant une infection COVID-19. À l’inverse, l’interrogatoire a identifié 2 patients (SpA traité par IFX et PR sous RTX) ayant eu des symptômes caractéristiques d’infection COVID-19 (anosmie/agueusie) confirmée par une PCR COVID-19 positive pour lesquels la sérologie est revenue négative. Conclusion La séroprévalence SarS-Cov-2 était de 2,8 % dans cette population de patients sous immunomodulateurs pour un RIC. Cette étude montre une prévalence des formes asymptomatiques (11 %) proche de celle observée en population générale.

Diagnostic performance of seven rapid IgG/IgM antibody tests and the Euroimmun IgA/IgG ELISA in COVID-19 patients.

OBJECTIVES: To evaluate the diagnostic performance of seven rapid IgG/IgM tests and the Euroimmun IgA/IgG ELISA for antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in COVID-19 patients. METHODS: Specificity was evaluated in 103 samples collected before January 2020. Sensitivity and time to seropositivity was evaluated in 167 samples from 94 patients with COVID-19 confirmed with RT-PCR on nasopharyngeal swab. RESULTS: Specificity (confidence interval) of lateral flow assays (LFAs) was ≥91.3% (84.0-95.5) for IgM, ≥90.3% (82.9-94.8) for IgG, and ≥85.4% (77.2-91.1) for the combination IgM OR IgG. Specificity of the ELISA was 96.1% (90.1-98.8) for IgG and only 73.8% (64.5-81.4) for IgA. Sensitivity 14-25 days after the onset of symptoms was between ≥92.1% (78.5-98.0) and 100% (95.7-100) for IgG LFA compared to 89.5% (75.3-96.4) for IgG ELISA. Positivity of IgM OR IgG for LFA resulted in a decrease in specificity compared to IgG alone without a gain in diagnostic performance, except for VivaDiag. The results for IgM varied significantly between the LFAs with an average overall agreement of only 70% compared to 89% for IgG. The average dynamic trend to seropositivity for IgM was not shorter than for IgG. At the time of hospital admission the sensitivity of LFA was <60%. CONCLUSIONS: Sensitivity for the detection of IgG antibodies 14-25 days after the onset of symptoms was ≥92.1% for all seven LFAs compared to 89.5% for the IgG ELISA. The results for IgM varied significantly, and including IgM antibodies in addition to IgG for the interpretation of LFAs did not improve the diagnostic performance.

A simple iterative map forecast of the COVID-19 pandemic (preprint)

We develop a simple 3-dimensional iterative map model to forecast the global spread of the coronavirus disease. Our model contains at most two fitting parameters, which we determine from the data supplied by the world health organisation for the total number of cases and new cases each day. We find that our model provides a surprisingly good fit to the currently-available data, which exhibits a cross-over from exponential to power-law growth, as lock-down measures begin to take effect. Before these measures, our model predicts exponential growth from day 30 to 69, starting from the date on which the world health organisation provided the first `Situation report' (21 January 2020 $-$ day 1). Based on this initial data the disease may be expected to infect approximately 23% of the global population, i.e. about 1.76 billion people, taking approximately 83 million lives. Under this scenario, the global number of new cases is predicted to peak on day 133 (about the middle of May 2020), with an estimated 60 million new cases per day. If current lock-down measures can be maintained, our model predicts power law growth from day 69 onward. Such growth is comparatively slow and would have to continue for several decades before a sufficient number of people (at least 23% of the global population) have developed immunity to the disease through being infected. Lock-down measures appear to be very effective in postponing the unimaginably large peak in the daily number of new cases that would occur in the absence of any interventions. However, should these measure be relaxed, the spread of the disease will most likely revert back to its original exponential growth pattern. As such, the duration and severity of the lock-down measures should be carefully timed against their potentially devastating impact on the world economy.