Utility of Epstein-Barr Virus DNA in Nasopharynx Swabs as a Reflex Test to Triage Seropositive Individuals in Nasopharyngeal Carcinoma Screening Programs.

BACKGROUND: Epstein-Barr virus (EBV) DNA detection in the nasopharynx is considered a biomarker for nasopharyngeal carcinoma (NPC). We evaluated its performance as a reflex test to triage EBV seropositives within an NPC screening program in China. METHODS: The study population was embedded within an ongoing NPC screening trial and included 1111 participants who screened positive for anti-EBV VCA (antibodies against EBV capsid antigens)/EBNA1 (EBV nuclear antigen1)-IgA antibodies (of 18 237 screened). Nasopharynx swabs were collected/tested for EBNA1 gene EBV DNA load. We evaluated performance of EBV DNA in the nasopharynx swab as a reflex test to triage EBV serological high-risk (those referred to endoscopy/MRI) and medium-risk (those referred to accelerated screening) individuals. RESULTS: By the end of 2019, we detected 20 NPC cases from 317 serological high-risk individuals and 4 NPC cases from 794 medium-risk individuals. When used to triage serological high-risk individuals, nasopharynx swab EBV DNA was detected in 19/20 cases (positivity rate among cases: 95.0%; 95% CI, 75.1%-99.9%), with a referral rate of 63.4% (201/317, 95% CI, 57.8%-68.7%) and NPC detection rate among positives of 9.5% (19/201, 95% CI, 5.8%-14.4%). The performance of an algorithm that combined serology with triage of serology high-risk individuals using EBV DNA testing yielded a sensitivity of 72.4% (95% CI, 3.0%-81.4%) and specificity of 97.6% (95% CI, 97.2%-97.9%). When used to triage EBV serological medium-risk individuals, the positivity rate among cases was 75.0% (95% CI, 19.4%-99.4%), with a referral rate of 61.8% (95% CI, 58.4%-65.2%) and NPC detection rate among positives of 0.6% (95% CI, 0.1%-1.8%). CONCLUSIONS: Nasopharynx swab EBV DNA showed promise as a reflex test to triage serology high-risk individuals, reducing referral by ca. 40% with little reduction in sensitivity compared to a serology-only screening program.

Amplified parallel antigen rapid test for point-of-care salivary detection of SARS-CoV-2 with improved sensitivity.

In the ongoing COVID-19 pandemic, simple, rapid, point-of-care tests not requiring trained personnel for primary care testing are essential. Saliva-based antigen rapid tests (ARTs) can fulfil this need, but these tests require overnight-fasted samples; without which independent studies have demonstrated sensitivities of only 11.7 to 23.1%. Herein, we report an Amplified Parallel ART (AP-ART) with sensitivity above 90%, even with non-fasted samples. The virus was captured multimodally, using both anti-spike protein antibodies and Angiotensin Converting Enzyme 2 (ACE2) protein. It also featured two parallel flow channels. The first contained spike protein binding gold nanoparticles which produced a visible red line upon encountering the virus. The second contained signal amplifying nanoparticles that complex with the former and amplify the signal without any linker. Compared to existing dual gold amplification techniques, a limit of detection of one order of magnitude lower was achieved (0.0064 ng·mL-1). AP-ART performance in detecting SARS-CoV-2 in saliva of COVID-19 patients was investigated using a case-control study (139 participants enrolled and 162 saliva samples tested). Unlike commercially available ARTs, the sensitivity of AP-ART was maintained even when non-fasting saliva was used. Compared to the gold standard reverse transcription-polymerase chain reaction testing on nasopharyngeal samples, non-fasting saliva tested on AP-ART showed a sensitivity of 97.0% (95% CI: 84.7-99.8); without amplification, the sensitivity was 72.7% (95% CI: 83.7-94.8). Thus, AP-ART has the potential to be developed for point-of-care testing, which may be particularly important in resource-limited settings, and for early diagnosis to initiate newly approved therapies to reduce COVID-19 severity.

Lactoferrin for the treatment of COVID-19 (Review).

The coronavirus disease 2019 (COVID-19) outbreak was caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The clinical outcomes of elderly individuals and those with underlying diseases affected by COVID-19 are serious, and may result in acute respiratory distress syndrome (ARDS) and even mortality. Currently, the clinical treatments for COVID-19 mostly involve symptom alleviation measures and non-specific broad spectrum antiviral drugs, as highly effective antiviral drugs and vaccines are not yet available. Lactoferrin (LF) is a safe iron-binding glycoprotein that is present in the milk of the majority of mammals and exhibits broad-spectrum antiviral activity, including against coronaviruses. In addition, LF also exhibits anti-inflammatory, anti-infective and immune-regulating properties, which are in line with the treatment requirements for SARS-CoV-2 infection. Therefore, the use of LF may be of value in the prevention and/or management of COVID-19. The aim of the present review was to summarize the previous reports on the antiviral properties of LF and compare these with the characteristics of SARS-CoV-2 infection, in order to determine whether LF could be used to assist in the prevention of COVID-19 and to investigate the possible underlying mechanisms governing its mode of action.

The Relationship between Psychological Impact and Self-control in Chinese Residents outside Hubei Province during the Epidemic of COVID-19: The mediation of self-regulated fatigue (preprint)

Aim: This study aimed to study the psychological impact of COVID-19 on Chinese residents outside the Hubei province and the relationship among impact of event, self-regulated fatigue and self-control. Subject and Methods: The 400 questionnaires had been collected through an online survey platform from 30th January to 2nd February in 2020 and included 4 parts: (1) sociodemographic data; (2)The revised version of the Impact of Event Scale(IES-R); (3) Self-Regulatory Fatigue Scale(SRF-S); (4)Self control scale (SCS). Results: (1)There were significant differences between different levels of sociodemographic variables on IES-R, SRF-S and SCS; (2) 75 (18.75%) residents reported a moderate-severe psychological impact; (3)There were significant differences between the previous researches and current study;(4)the high-score group of SCS had got significantly higher scores on SRF-S and IES-R. (5) Self-regulated fatigue partially mediated the relationship between impact of event and self-control. Conclusion: We found that the residents suffered a psychological impact during the outbreak of COVID-19 .The more self-control they were, the more self-regulated fatigue and psychological impact they suffered, and self-control could not only had an direct influence on psychological impact but also had affected it indirectly through self-regulated fatigue.