Citral modulates human monocyte responses to Staphylococcus aureus infection

Staphylococcus aureus is a Gram-positive bacterium that is considered an important human pathogen. Due to its virulence and ability to acquire mechanisms of resistance to antibiotics, the clinical severity of S. aureus infection is driven by inflammatory responses to the bacteria. Thus, the present study aimed to investigate the modulating role of citral in inflammation caused by S. aureus infection. For this, we used an isolate obtained from a nasal swab sample of a healthy child attending a day-care centre in Vitória da Conquista, Bahia, Brazil. The role of citral in modulating immunological factors against S. aureus infection was evaluated by isolating and cultivating human peripheral blood mononuclear cells. The monocytes were treated with 4%, 2%, and 1% citral before and after inoculation with S. aureus. The cells were analysed by immunophenotyping of monocyte cell surface molecules (CD54, CD282, CD80, HLA-DR, and CD86) and cytokine dosage (IL-1β, IL-6, IL-10, IL-12p70, IL-23, IFN-γ, TGF-β, and TNF-α), and evaluated for the expression of 84 genes related to innate and adaptive immune system responses. GraphPad Prism software and variables with P values < 0.05, were used for statistical analysis. Our data demonstrated citral’s action on the expression of surface markers involved in recognition, presentation, and migration, such as CD14, CD54, and CD80, in global negative regulation of inflammation with inhibitory effects on NF-κB, JNK/p38, and IFN pathways. Consequently, IL-1β, IL-6, IL-12p70, IL-23, IFN-γ, and TNF-α cytokine expression was reduced in groups treated with citral and groups treated with citral at 4%, 2%, and 1% and infected, and levels of anti-inflammatory cytokines such as IL-10 were increased. Furthermore, citral could be used as a supporting anti-inflammatory agent against infections caused by S. aureus. There are no data correlating citral, S. aureus, and the markers analysed here; thus, our study addresses this gap in the literature.

Usability of an At-Home Anterior Nares SARS-CoV-2 RT-PCR Sample Collection Kit: Human Factors Feasibility Study (Preprint)

BACKGROUND Readily available testing for SARS-CoV-2 is necessary to mitigate COVID-19 disease outbreaks. At-home collection kits, in which samples are self-collected without requiring a laboratory or clinic visit and sent to an external laboratory for testing, can provide convenient testing to those with barriers to access. They can prevent unnecessary exposure between patient and clinical staff, increase access for patients with disabilities or remote workers, and decrease burdens on health care resources, such as provider time and personal protective equipment. Exact Sciences developed an at-home collection kit for samples to be tested to detect SARS-CoV-2 that includes an Instructions for Use (IFU) document, which guides people without prior experience on collecting a nasal swab sample. Demonstrating successful sample collection and usability is critical to ensure that these samples meet the same high-quality sample collection standards as samples collected in clinics. OBJECTIVE The aim of this study was to determine the usability of a SARS-CoV-2 at-home nasal swab sample collection kit. METHODS A human factors usability study was conducted with 30 subjects without prior medical, laboratory, or health care training and without COVID-19 sample self-collection experience. Subjects were observed while they followed the IFU for the at-home sample collection portion of the SARS-CoV-2 test in a setting that simulated a home environment. IFU usability was further evaluated by requiring the subjects to complete a survey, answer comprehension questions, provide written feedback, and respond to questions from the observer about problems during use. RESULTS All 30 subjects successfully completed the sample collection process, and all 30 samples were determined by reverse transcription–polymerase chain reaction (RT-PCR) testing to meet quality standards for SARS-CoV-2 testing. The subjects’ written feedback and comments revealed several recommendations to improve the IFU. CONCLUSIONS The study demonstrated the overall usability of an at-home SARS-CoV-2 collection kit. Various feedback mechanisms provided opportunities to improve the wording and graphics for some critical tasks, including placing the label correctly on the tube. A modified IFU was prepared based on study outcomes.

SARS-CoV-2 Positivity in Asymptomatic-Screened Dental Patients

Enhanced community surveillance is a key pillar of the public health response to coronavirus disease 2019 (COVID-19). Asymptomatic carriage of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a potentially significant source of transmission, yet remains relatively poorly understood. Disruption of dental services continues with significantly reduced capacity. Ongoing precautions include preappointment and/or at appointment COVID-19 symptom screening and use of enhanced personal protective equipment (PPE). This study aimed to investigate SARS-CoV-2 infection in dental patients to inform community surveillance and improve understanding of risks in the dental setting. Thirty-one dental care centers across Scotland invited asymptomatic-screened patients aged over 5 y to participate. Following verbal consent and completion of sociodemographic and symptom history questionnaire, trained dental teams took a combined oropharyngeal and nasal swab sample using standardized Viral Transport Medium–containing test kits. Samples were processed by the Lighthouse Lab and patients informed of their results by SMS/email with appropriate self-isolation guidance in the event of a positive test. All positive cases were successfully followed up by the national contact tracing program. Over a 13-wk period (from August 3, 2020, to October 31, 2020), 4,032 patients, largely representative of the population, were tested. Of these, 22 (0.5%; 95% CI, 0.5%–0.8%) tested positive for SARS-CoV-2. The positivity rate increased over the period, commensurate with uptick in community prevalence identified across all national testing monitoring data streams. To our knowledge, this is the first report of a COVID-19 testing survey in asymptomatic-screened patients presenting in a dental setting. The positivity rate in this patient group reflects the underlying prevalence in community at the time. These data are a salient reminder, particularly when community infection levels are rising, of the importance of appropriate ongoing infection prevention control and PPE vigilance, which is relevant as health care team fatigue increases as the pandemic continues. Dental settings are a valuable location for public health surveillance.

Low prevalence of COVID-19 Exposure is Coincident with Self-reported Compliance with Public Health Guidelines among Essential Employees at an Institute of Higher Education

ImportanceDetailed analysis of infection rates paired with behavioral and employee reported risk factors are vital to understanding how COVID-19 transmission may be inflamed or mitigated in the workplace. Institutes of Higher Education are heterogeneous work units that supported continued in person employment during COVID-19, providing an excellent test site for occupational health evaluation.ObjectiveTo evaluate self-reported behaviors and SARS-CoV-2 among essential in-person employees during the first six months of the COVID-19 pandemic.DesignCross-sectional, conducted from July 13-September 2, 2020.SettingInstitute of Higher Education in Fort Collins, Colorado.ParticipantsEmployees identified to be an essential in-person employee during the first six months of the pandemic (1,522 invited, 1,507 qualified, 603 (40%) completed the survey). Of those completing the survey, 84.2% (508) elected to participate in blood and nasal swab sample collection to assess active SARS-CoV-2 infection via qRT-PCR, and past infection by serology (overall completion rate of 33.7%). Eligibility included > 18 years old, able to read and understand English, not currently experiencing cough, shortness of breath or difficulty breathing, fever >100.4F (38C), chills/shaking with chills, muscle pain, new or worsening headaches, sore throat or new loss of sense of taste/smell.ExposureSelf-reported COVID-19 protective behaviorsMain Outcome(s) and Measure(s)Current SARS-CoV-2 infection detected by qRT-PCR or previous SARS-CoV-2 infection detected by IgG SARS-CoV-2 testing platform.ResultsThere were no qRT-PCR positive tests, and only 2 (0.39%) contained seroreactive IgG antibodies. Participants were 60% female, 90% non-Hispanic white, mean age 41 years (18-70 years). Handwashing and mask wearing were reported frequently both at work (98% and 94% respectively) and outside work (91% and 95% respectively) while social distancing was reported less frequently at work (79%) then outside of work (92%) [p < .001]. Participants were more highly motivated to avoid exposures out of concern for spreading to others (83%) than for personal implications (63%) [p < .001].Conclusions and RelevanceThis is one of the first reports to document that complex work environments can be operated safely during the COVID-19 pandemic when employees report compliance with public health practices both at and outside work.

SARS-CoV-2 positivity in asymptomatic-screened dental patients

Enhanced community surveillance is a key pillar of the public health response to COVID-19. Asymptomatic carriage of SARS-CoV-2 is a potentially significant source of transmission, yet remains relatively poorly understood. Disruption of dental services continues with significantly reduced capacity. Ongoing precautions include pre- and/or at appointment COVID-19 symptom screening and use of enhanced personal protective equipment (PPE). This study aimed to investigate SARS-CoV-2 infection in dental patients to inform community surveillance and improve understanding of risks in the dental setting. Thirty-one dental care centres across Scotland invited asymptomatic screened patients over 5-years-old to participate. Following verbal consent and completion of sociodemographic and symptom history questionnaire, trained dental teams took a combined oropharyngeal and nasal swab sample using standardised VTM-containing testkits. Samples were processed by the Lighthouse Lab and patients informed of their results by SMS/e-mail with appropriate self-isolation guidance in the event of a positive test. Over a 13-week period (from 3August to 31October2020) n=4,032 patients, largely representative of the population, were tested. Of these n=22 (0.5%; 95%CI 0.5%, 0.8%) tested positive for SARS-CoV-2. The positivity rate increased over the period, commensurate with uptick in community prevalence identified across all national testing monitoring data streams. All positive cases were successfully followed up by the national contact tracing program. To the best of our knowledge this is the first report of a COVID-19 testing survey in asymptomatic-screened patients presenting in a dental setting. The positivity rate in this patient group reflects the underlying prevalence in community at the time. These data are a salient reminder, particularly when community infection levels are rising, of the importance of appropriate ongoing Infection Prevention Control and PPE vigilance, which is relevant as healthcare team fatigue increases as the pandemic continues. Dental settings are a valuable location for public health surveillance.

Determining the Prevalence of Nasal Community-acquired MRSA Carriage and Associated Risk Factors in the Turkish Cypriot Population

Introduction: No studies have investigated Community-Acquired Methicillin-Resistant Staphylococcus aureus (CA-MRSA) nasal carriage rate in the Turkish Cypriot community up to now. The aim of this study was to investigate (i) The prevalence of CA-MRSA nasal carriage in the Turkish Cypriot community, (ii) The association of previously identified risk factors with CA-MRSA. Materials and Methods: Our study is a cross-sectional study conducted in Northern Cyprus in 2019 with 487 randomly selected and voluntary participants. In this study, a questionnaire was distributed, and the relationship between nasal CA-MRSA carriage and risk factors was investigated. In addition, the presence of CA-MRSA was determined by taking a nasal swab sample. Results: In this study, the prevalence of nasal CA-MRSA carriage in the Turkish Cypriot society was 6.98% (34/487). Marital status was found to be the only significant risk factor associated with CA-MRSA carriage (p= 0.035) in the study. However, it was found that individuals exposed to risk factors of “hospitalization during the previous year” and “using antibiotic during the last year” were 1.6 and 3.25 times higher than those who did not, respectively. Conclusion: In this study, “marital status” was the only statistically significant risk factor associated with CA-MRSA carriage. Furthermore, the prevalence of nasal CA-MRSA carriage in the Turkish Cypriot population was found to be higher than developed countries. In this context, it is essential to develop health strategies for the sustainability of TK-MRSA carriage surveillance and to reduce carriage.

COVID-19 presented with Deep Vein Thrombosis: An unusual case report

BackgroundOn 31 December 2019, the World Health Organization (WHO) was informed of a cluster of cases of pneumonia of unknown cause detected in Wuhan City, Hubei Province, China. The pneumonia was caused by a virus called SARS-Cov-2, which was later named COVID-19. In this report, we present a patient with COVID-19 who developed deep vein thrombosis.Case presentationA 57-year-old woman presented to the clinic's infectious department with no underlying illness due to pain, redness, and leg swelling. According to a patient report, she had a mild dry cough for the past 3 days and had no other symptoms. The patient had no history of prone thrombosis conditions. Initially, CT angiography was performed to rule out pulmonary thromboembolism, which showed no evidence of thrombosis. Dilatation and thrombosis were seen in the examinations of the paired veins of the leg, popliteal, superficial and left femoral joints, and no evidence of vascular flow suggesting acute DVT. Because of fever and lymphopenia, nasal swabs were used for sampling and SARS-CoV-2 nucleic acid was detected by RT-PCR. Chest X-ray also revealed bilateral patchy ground-glass opacity. Other tests including ANA, Anti-dsDNA, RF test and ACA test was normal. Heparin at a dose of 80 units/kg IV bolus, chloroquine 400 mg single dose and lopinavir/ritonavir (Kaletra) 400 mg twice daily were prescribed to treat illness and relieve symptoms. On illness day 3, fever stopped and nasal swab sample turned undetectable for SARS-CoV-2 by RT-PCR as well as swelling and tenderness on her leg had been disappeared gradually. She is under regular follow-up with no new symptoms to date.Conclusion The mechanism of DVT formation due to COVID-19 is unknown despite thrombocytopenia, and has not been investigated but it resolved as COVID-19 symptoms, tenderness, and leg pain improved. Although COVID-19 presented with Deep Vein Thrombosis is a rare condition, in middle-aged people with sudden onset of manifestations, we should recognize it from other diseases as an important and treatable differential diagnosis. Rapid diagnostic assays, efficient treatment, and prudent use of CT-scan are important to control future COVID-19 spread.

3 Administration of a DNA immunostimulant does not mitigate bovine herpesvirus-1 recrudescence in dexamethasone challenged beef cattle

The study objective was to determine the effect of a DNA immunostimulant on recrudescence of bovine herpesvirus-1 (BHV-1) after dexamethasone challenge in beef cattle. It was hypothesized that the DNA immunostimulant would mitigate stress-induced immunosuppression; thereby, reducing the incidence of BHV-1 recrudescence. Steers (n = 10) and heifers (n = 10; initial BW = 489 kg ± 57 kg) were stratified by pre-existing BHV-1 antibody titer, sex and initial BW and randomly assigned to treatment (n = 4 pens/treatment; 2 or 3 animals/pen). All calves were administered 40 mg of dexamethasone i.v. at 0600 h from d 0 to 2, 166-d subsequent to BHV-1 challenge with 1.0 × 108 plaque-forming units per nostril. On d 1, calves were administered treatments consisting of 2 mL i.m. of DNA immunostimulant (Zelnate; ZEL) or sterile saline (CON). Once daily (0600) from d 0 to 12, a whole blood was obtained via jugular venipuncture for complete blood count (CBC) analysis and nasal swabs were collected to determine BHV-1 prevalence via virus isolation testing. A repeated measures mixed model was used to test the effect of treatment, day and their interaction for CBC variables. There was a treatment × day interaction for eosinophils (P = 0.02) and percent eosinophils (P = 0.03). Eosinophils were greater (P < 0.01) for ZEL on d 3 and 6 post-dexamethasone challenge. On d 11 and 12, eosinophils for CON rebounded such that their concentration was greater than ZEL (P < 0.01). Lymphocytes, neutrophil and monocyte concentration did not differ (P ≥ 0.44); however, a day effect (P ≤ 0.01) existed such that each variable increased transiently after dexamethasone challenge. All cattle had BHV-1 present in a nasal swab sample on at least one sample day, with prevalence of BHV-1 in nasal swab samples being greatest on d 5 (80% positive; P = 0.01). However, no treatment differences were detected for BHV-1 prevalence in this study. The DNA immunostimulant altered eosinophil concentrations but did not mitigate BHV-1 recrudesce after dexamethasone challenge

104 Administration of a DNA immunostimulant does not mitigate bovine herpesvirus-1 recrudescence in dexamethasone challenged beef cattle

The study objective was to determine the effect of a DNA immunostimulant on recrudescence of bovine herpesvirus-1 (BHV-1) after dexamethasone challenge in beef cattle. It was hypothesized that the DNA immunostimulant would mitigate stress-induced immunosuppression; thereby, reducing the incidence of BHV-1 recrudescence. Steers (n=10) and heifers (n=10; initial BW = 489 kg ± 57 kg) were stratified by pre-existing BHV-1 antibody titer, sex and initial BW and randomly assigned to treatment (n=4 pens/treatment; 2 or 3 animals/pen). All calves were administered 40 mg of dexamethasone i.v. at 0600 h from d 0 to 2, 166-d subsequent to BHV-1 challenge with 1.0 × 108 plaque-forming units per nostril. On d 1, calves were administered treatments consisting of 2 mL i.m. of DNA immunostimulant (Zelnate; ZEL) or sterile saline (CON). Once daily (0600) from d 0 to 12, a whole blood was obtained via jugular venipuncture for complete blood count (CBC) analysis and nasal swabs were collected to determine BHV-1 prevalence via virus isolation testing. A repeated measures mixed model was used to test the effect of treatment, day and their interaction for CBC variables. There was a treatment × day interaction for eosinophils (P = 0.02) and percent eosinophils (P = 0.03). Eosinophils were greater (P < 0.01) for ZEL on d 3 and 6 post-dexamethasone challenge. On d 11 and 12, eosinophils for CON rebounded such that their concentration was greater than ZEL (P < 0.01). Lymphocytes, neutrophil and monocyte concentration did not differ (P ≥ 0.44); however, a day effect (P ≤ 0.01) existed such that each variable increased transiently after dexamethasone challenge. All cattle had BHV-1 present in a nasal swab sample on at least one sample day, with prevalence of BHV-1 in nasal swab samples being greatest on d 5 (80% positive; P = 0.01). However, no treatment differences were detected for BHV-1 prevalence in this study. The DNA immunostimulant altered eosinophil concentrations but did not mitigate BHV-1 recrudesce after dexamethasone challenge

Resistance pattern of methicillin resistant Staphylococcus aureus among nasal isolates of HIV infected patients in a tertiary care hospital

Background: Patients infected with HIV have an increased risk of nasal Staphylococcus aureus carriage as well as consecutive staphylococcal infections and is a major reservoir for MRSA which is potential risk factors for community acquired MRSA. Knowing the Nasal carriage status of Staphylococcus aureus and their Antibiogram will be beneficial for effective management of these patients.Methods: Nasal swab sample were collected from all the participants and processed for culture and identification of Staphylococcus aureus and their antimicrobial sensitivity. All the Staphylococcus aureus isolates were tested for Methicillin resistance by Oxacillin screen agar test, cefoxitin disc diffusion test and further confirmed by mecA gene PCR.Results: In this study out of 220 HIV seropositive patients, 43.64% isolates were confirmed to be S. aureus, 18.75% MRSA and 81.25% were MSSA. Cefoxitin disc diffusion showed 100% specificity (95% CI; 97.05%-100.00%), 100% sensitivity (95% CI; 83.89-100.00%) and 100% accuracy (95% CI; 97.47% to 100.00%) while comparing with gold standard mecA gene PCR. Among the nasal carriers; males (60%) ware dominant on females (40%). 31-50 years age group was strongly associated with MRSA nasal carriage. None of the isolates were resistant against lenozolid, teicoplanin and vancomycin while ampicillin (75%), ciprofloxacin (62.5%), clindamycin (59.38%) and cotrimoxazole (53.13%) showed increased resistance against S. aureus nasal carriage.Conclusions: Resistance among HIV positive persons for all antibiotics showed statistically significant while compared to control group. Cefoxitin disc diffusion can be used as surrogate agent for mecA gene detection.