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Cytokines in wound fluid are used as surrogates for wound healing in clinical research. The current methods used to collect and process wound fluid are noninvasive but not optimal. The aim of this prospective study was to evaluate a method (NovaSwab) by which wound fluid is collected by a surface swab and eluted in a physiological buffer for subsequent cytokine analysis. Wound fluid from 12 patients with leg ulcers was assessed by NovaSwab at the start (Day 0) and at the end of a 23-h collection period of wound fluid retained by foam oblates beneath an occlusive film dressing (Day 1). GM-CSF, IL-1 alpha, IL-1 beta, IL-6, IL-8, PDGF-AA, TNF-alpha and VEGF levels were measured by multiplex and electrochemiluminescence assays. IL-1 alpha (2.4x), IL-1 beta (2.0x) and IL-8 (1.8x) levels increased from Day 0 to Day 1 as detected by NovaSwab, indicating local production of these polypeptides in the wounds. On Day 1, the NovaSwab method yielded higher levels of IL-1 alpha (4.0x), IL-1 beta (2.7x) and IL-6 (2.7x), and 35% lower levels of VEGF than those in wound fluid accumulated for 23 h in foam oblates (on average, 5 ml of wound fluid). In vitro experiments showed that the investigated cytokines in cell-free wound fluid were recovered in a quantitative manner by the NovaSwab method. We conclude that the method presented here is a promising research tool to study the kinetics of soluble cytokines over the course of wound healing. More studies are needed to determine the interobserver variation and reproducibility of the NovaSwab method.

There is an increasing need for inexpensive and rapid screening tests in point-of-care clinical oncology settings. Herein, we develop a swab “dip” test in saliva obtained from consenting patients participating in a lung-cancer-screening programme being undertaken in North West England. In a pilot study, a total of 211 saliva samples (n = 170 benign, 41 designated cancer-positive) were randomly taken during the course of this prospective lung-cancer-screening programme. The samples (sterile Copan blue rayon swabs dipped in saliva) were analysed using attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy. An exploratory analysis using principal component analysis (PCA,) with or without linear discriminant analysis (LDA), was then undertaken. Three pairwise comparisons were undertaken including: (1) benign vs. cancer following swab analysis; (2) benign vs. cancer following swab analysis with the subtraction of dry swab spectra; and (3) benign vs. cancer following swab analysis with the subtraction of wet swab spectra. Consistent and remarkably similar patterns of clustering for the benign control vs. cancer categories, irrespective of whether the swab plus saliva sample was analysed or whether there was a subtraction of wet or dry swab spectra, was observed. In each case, MANOVA demonstrated that this segregation of categories is highly significant. A k-NN (using three nearest neighbours) machine-learning algorithm also showed that the specificity (90%) and sensitivity (75%) are consistent for each pairwise comparison. In detailed analyses, the swab as a substrate did not alter the level of spectral discrimination between benign control vs. cancer saliva samples. These results demonstrate a novel swab “dip” test using saliva as a biofluid that is highly applicable to be rolled out into a larger lung-cancer-screening programme.

The current pandemic has generated the search for new reliable and economic alternatives for the detection of SARS-CoV-2, which produces the COVID-19 disease, one of the recommendations by the World Health Organization, is the detection of the virus by RT-qPCR methods from upper respiratory tract samples. The discomfort of the pharyngeal nasopharyngeal swab described by patients, the requirement of trained personnel, and the generation of aerosols, are factors that increase the risk of infections in this type of intake. It is known that the main means of transmission of SARS-CoV-2 is through aerosols or small droplets, which is why saliva is important as a relevant means of detecting COVID-19. In this study, a modified method based on SARS-CoV-2 RNA release from saliva is described, avoiding the isolation and purification of the genetic material and its quantification of viral copies; the results are compared with paired pharyngeal/nasopharyngeal swab samples (EF/EN). Results showed good agreement in saliva samples compared to EF/EN samples. On average, a sensitivity for virus detection of 80% was demonstrated in saliva samples competing with EF/EN samples. The use of saliva is a reliable alternative for the detection of SARS-CoV-2 by means of RT-PCR in the first days of infection, having important advantages over the conventional method. Saliva still needs to be studied completely to evaluate the detection capacity of the SARS-CoV-2 nucleic acid, however, the described process is viable, due to the decrease in materials and supplies, process times, the increment in the sampling and improvement of laboratory performance.

To characterize COVID-19 epidemiology, numerous population-based studies have been undertaken to model the risk of SARS-CoV-2 infection. Less is known about what may drive the probability to undergo testing. Understanding how much testing is driven by contextual or individual conditions is important to delineate the role of individual behavior and to shape public health interventions and resource allocation. In the Val Venosta/Vinschgau district (South Tyrol, Italy), we conducted a population-representative longitudinal study on 697 individuals susceptible to first infection who completed 4,512 repeated online questionnaires at four week intervals between September 2020 and May 2021. Mixed-effects logistic regression models were fitted to investigate associations of self-reported SARS-CoV-2 testing with individual characteristics (social, demographic, and biological) and contextual determinants. Testing was associated with month of reporting, reflecting the timing of both the pandemic intensity and public health interventions, COVID-19-related symptoms (odds ratio, OR:8.26; 95% confidence interval, CI:6.04–11.31), contacts with infected individuals within home (OR:7.47, 95%CI:3.81–14.62) or outside home (OR:9.87, 95%CI:5.78–16.85), and being retired (OR:0.50, 95%CI:0.34-0.73). Symptoms and next within- and outside-home contacts were the leading determinants of swab testing predisposition in the most acute phase of the pandemics. Testing was not associated with age, sex, education, comorbidities, or lifestyle factors. In the study area, contextual determinants reflecting the course of the pandemic were predominant compared to individual sociodemographic characteristics in explaining the SARS-CoV-2 probability of testing. Decision makers should evaluate whether the intended target groups were correctly prioritized by the testing campaign.

Swabs are useful and common sampling tools in various research fields, such as medicine, ecology, biotechnology, forensic medicine, and pollutant monitoring systems. Collection reagents are one of the essential components in sampling. It is important to develop a sample collection kit and designate an appropriate storage temperature because samples need to be stored for a long time. The purpose of this study was to identify the effects of three collection reagents and three storage temperatures on the recovery of living bacteria without media. We selected Escherichia coli and Staphylococcus aureus as representative environmental bacteria. Distilled water (DW), phosphate buffered saline (PBS), and Tris-EDTA (TE) buffer were used as collection reagents and stored at 22°C, 4°C, and −70°C after sampling. The results of using each collection reagent and storage temperature on the bacteria were compared using relative light units (RLU) and the number of colony forming units (CFU). When using −70°C storage temperature and the TE buffer, the number of living bacteria and the RLU values remained constant. It is therefore recommended that the sample be stored at −70°C immediately after collection and a TE buffer solution be used as the collection reagent.

Introduction In the coronavirus disease 2019 era, debate around the risk of contagion in school is intense in Italy. The Department of Welfare and Health of Florence promoted a screening campaign with rapid antigen tests for all students and school personnel. The aim of this study was to assess the circulation of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in the school setting by means of mass screening in every primary and middle school in Florence. Methods All students and school personnel at primary and middle schools in Florence were asked to take part. The campaign started on 16 November 2020 and was completed on 12 February 2021. If a subject had a positive result on rapid antigen testing, a molecular test was performed to confirm the result. Results In total, 18,414 subjects were tested: 15,233 students (82.7%) and 3181 school personnel (17.3%). The rapid antigen test gave a positive result in 27 cases (0.15%). Of these, only 14 tests were confirmed to be positive on molecular testing. These results show a very low number of cases of SARS-CoV-2 among the study subjects (0.08%). Conclusions These results show that the spread of SARS-CoV-2 in the school setting was low in Florence during the screening period.

Aethina tumida (Coleoptera: Nitidulidae - Small Hive Beetle - SHB), is a parasite of honey bee colonies that causes the notifiable disease called aethinosis. In 2014, SHB was detected in Southern Italy, where it is still present (Calabria region). As part of surveillance activities, official diagnosis of the disease is performed by veterinary services via visual inspection of single hives in the apiaries. New outbreaks can be eradicated and the spread of SHBs limited by early detection of new introductions. We report an alternative protocol for the diagnosis of SHB through swabs and hive debris analysis by PCR. This was tested in three apiaries through the evaluation of different SHB infestation levels with a hive inspection method. This approach for sampling, followed by biomolecular methods, was fast and useful in unfavorable conditions (bad weather, aggressiveness, robbing), could be integrated in the official diagnosis procedures and may act as pre-clinic indicator.

Oral cancer is one of the leading causes of morbidity and mortality globally. There is a lack of studies on the growth of different Candida species in swab pre and post-radiotherapy. Hence, this study aimed to determine different Candida species in the oral cavity of patients who undergo radiotherapy. The study included 50 patients with oral cancer scheduled to undergo radiotherapy. Both saliva and swab samples were collected from all the patients before and after two- and six weeks of starting the radiotherapy. Similar inoculation was performed using the salivary swabs and incubated aerobically at 37°C for 48h. After 48h, culture plates were removed from the incubator and observed for the growth of different fungal species based on the color of the colonies. The culture of samples from patients with oral cancer resulted in the growth of 68% of Candida species in saliva and 44% in swab before initiating radiation. Unlike baseline findings, Candida albicans were identified in a higher number in swab samples (44%) than saliva (24%) post two weeks of radiotherapy. All saliva samples were positive to candida species, in which Candida albicans shows high prevalence (24%). After six weeks of radiotherapy, in the swab, 30% of samples were positive for Candida albicans, and 18% of samples were positive for non-albicans species. Before radiotherapy, at two weeks and six weeks of radiotherapy, saliva samples showed a higher prevalence of Candidal species compared to swab samples. The combination of other Candida species was also higher in saliva samples compared to swab samples during radiotherapy.

Surface sampling is a frequent task in laboratory work and field studies. Simple methods usually have low efficiency in collecting target substances from surfaces. This study developed an advanced tape-stripping approach for efficient sampling on non-absorbent surfaces. A film-forming solution, prepared using polyvinyl alcohol, is applied to the target surface, where it covers and engulfs the surface deposits and then solidifies into an elastic membrane as it is exposed to air. The deposits are collected by stripping off the membrane and re-dissolving it in water. This new approach exhibited an efficiency of 100% in collecting uniform-size microspheres from glass surfaces and extremely high efficiencies (>96.6%) in detecting selected target DNA materials from glass and stainless steel surfaces. In comparison, the common swab-rinse method exhibited an efficiency of 72.6% under similar measuring conditions. The viability of S. aureus during sampling using the new approach decreased as the ethanol concentration in the applied solution increased. Using a solution with a mass ratio of ethanol of 17.6% balanced the effects of multiplication and degradation of the S. aureus on glass surfaces during sampling. Overall, the proposed approach exhibits high efficiency in collecting living and abiotic matter from non-absorbent surfaces, complementing existing sampling methods.

UNLABELLED: Monitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on surfaces is emerging as an important tool for identifying past exposure to individuals shedding viral RNA. Our past work has demonstrated that SARS-CoV-2 reverse transcription-quantitative PCR (RT-qPCR) signals from surfaces can identify when infected individuals have touched surfaces such as Halloween candy, and when they have been present in hospital rooms or schools. However, the sensitivity and specificity of surface sampling as a method for detecting the presence of a SARS-CoV-2 positive individual, as well as guidance about where to sample, has not been established. To address these questions, and to test whether our past observations linking SARS-CoV-2 abundance to Rothia spp. in hospitals also hold in a residential setting, we performed detailed spatial sampling of three isolation housing units, assessing each sample for SARS-CoV-2 abundance by RT-qPCR, linking the results to 16S rRNA gene amplicon sequences to assess the bacterial community at each location and to the Cq value of the contemporaneous clinical test. Our results show that the highest SARS-CoV-2 load in this setting is on touched surfaces such as light switches and faucets, but detectable signal is present in many non-touched surfaces that may be more relevant in settings such as schools where mask wearing is enforced. As in past studies, the bacterial community predicts which samples are positive for SARS-CoV-2, with Rothia sp. showing a positive association. IMPORTANCE: Surface sampling for detecting SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is increasingly being used to locate infected individuals. We tested which indoor surfaces had high versus low viral loads by collecting 381 samples from three residential units where infected individuals resided, and interpreted the results in terms of whether SARS-CoV-2 was likely transmitted directly (e.g. touching a light switch) or indirectly (e.g. by droplets or aerosols settling). We found highest loads where the subject touched the surface directly, although enough virus was detected on indirectly contacted surfaces to make such locations useful for sampling (e.g. in schools, where students do not touch the light switches and also wear masks so they have no opportunity to touch their face and then the object). We also documented links between the bacteria present in a sample and the SARS-CoV-2 virus, consistent with earlier studies.

Hany Mahmoud,1 Ahmed Hamody,2 Hesham M Hefny,3 Dalia Tohamy,4 Islam Awny5 1Department of Ophthalmology, Faculty of Medicine, Sohag University, Sohag, Egypt; 2Anesthesia Department, Sohag University, Sohag, Egypt; 3Clinical Pathology Department, Sohag University, Sohag, Egypt; 4Ophthalmology Department, Assiut University, Assiut, Egypt; 5Department of Ophthalmology, Sohag University, Sohag, EgyptCorrespondence: Hany MahmoudDepartment of Ophthalmology, Faculty of Medicine, Sohag University, EgyptTel +20 1024368111Email drhanymahmoud@gmail.comPurpose: To assess the presence of anti-SARS-CoV-2 IgA in the conjunctival secretions of confirmed COVID-19 patients by nasopharyngeal swabs and correlate its presence with the severity of the disease, patient’s age, sex and ocular symptoms.Methods: This study included 44 positive COVID-19 patients confirmed with nasopharyngeal swabs during the period 17– 28 February 2021 at Sohag Tropical Medicine Hospital. Tears and conjunctival secretions were examined for the presence of anti-SARS-CoV-2 IgA.Results: While non-reactive results are strongly correlated to low titre and vice versa, severity showed significant correlation with neither IgA reactivity nor titre. Meanwhile, IgA reactivity did not show significant correlation with either age or sex. The reactivity and IgA titre are correlated with ocular symptoms.Conclusion: The anti-SARS-CoV-2 IgA could be found in ocular secretions in SARS-CoV-2 patients. There is no correlation with age or sex or severity of the disease; however, they are correlated with ocular symptoms.Keywords: anti-SARS-CoV-2 IgA, ocular, secretions, swab

Purpose: To evaluate the results of conjunctival and nasopharyngeal swab tests in patients with confirmed COVID-19. Methods: This prospective study included 45 patients who were hospitalized for confirmed COVID-19. Nasopharyngeal swab samples were obtained from the patients before hospitalization. Only one eye of each patient was randomly selected for-conjunctival sampling. All participants underwent a complete slit- lamp examination. Conjunctival and nasopharyngeal swab samples were analyzed by reversetranscriptase-polymerase-chain reaction (RT-PCR). Results: Twenty seven (60%) of the patients were male and 18 (40%) were female. Conjunctival swab was positive in only one (2.22%) patient. None of the COVID-19 patients showed ocular changes and symptoms. There were no abnormalities of the ocular surface, anterior chamber or posterior segment at slit-lamp examination. Conclusions: The RT-PCR was not high positive in the conjunctiva as in nasopharyngeal swabs. Ocular changes were not common in COVID-19 patients.

The aim of this study was to evaluate the impact of different moistening agents (RNase-free water, absolute anhydrous ethanol, RNAlater®) applied to collection swabs on DNA/RNA retrieval and integrity for capillary electrophoresis applications (STR typing, cell type identification by mRNA profiling). Analyses were conducted on whole blood, luminol-treated diluted blood, saliva, semen, and mock skin stains. The effects of swab storage temperature and the time interval between sample collection and DNA/RNA extraction were also investigated. Water provided significantly higher DNA yields than ethanol in whole blood and semen samples, while ethanol and RNAlater® significantly outperformed water in skin samples, with full STR profiles obtained from over 98% of the skin samples collected with either ethanol or RNAlater®, compared to 71% of those collected with water. A significant difference in mRNA profiling success rates was observed in whole blood samples between swabs treated with either ethanol or RNAlater® (100%) and water (37.5%). Longer swab storage times before processing significantly affected mRNA profiling in saliva stains, with the success rate decreasing from 91.7% after 1 day of storage to 25% after 7 days. These results may contribute to the future development of optimal procedures for the collection of different types of biological traces.

The coronavirus disease 2019 (COVID-19) pandemic has caused an international shortage of nasopharyngeal flocked swabs, which are one of the main supplies for diagnostic testing In response to this issue, our institution developed locally made nasopharyngeal swabs This report aims to provide a clinical evaluation by conducting a sterility test, reverse transcription polymerase chain reaction (RT-PCR) compatibility test, and a user-based survey test of two batches of locally made flocked swabs Sterility and compatibility tests were conducted at our microbiology laboratory Participants with clinical suspicion of COVID-19 were scheduled for swab tests using Flocked Swab HS-19 and samples obtained were tested using the RT-PCR method The cycle threshold (Ct) value of the samples was recorded A user-based survey was conducted to evaluate the swab stick and flocked-fiber tip performance The sterility test showed no evidence of bacterial growth on both blood agar and thioglycolate medium RT-PCR compatibility test from Ct value of 33 samples of the first batch and 30 samples of the second batch was recorded with a mean Ct of 27 17±2 96 and 23 99±2 18, respectively Six parameters of the swab stick (comfortability, smoothness, flexibility, durability, applicability, and breakpoint performance) showed satisfactory scores with an average of 4 14 out of 5 0 for the first batch and 4 16 for the second batch, while 4 parameters of the flocked-fiber tip (fiber adherence, thickness, symmetricity, and sample collection sufficiency) revealed acceptable scores with an average of 3 6 out of 5 0 for the first batch and 3 75 for the second batch This study indicates that locally made flocked swabs are satisfactory and clinically applicable for testing and diagnosing COVID-19 Furthermore, mass production and distribution across the country are expected The development of these swabs, which involved multidisciplinary teamwork and various industrial partners, portrayed a valuable lesson on how to cope with the pandemic through innovation © 2020 All Rights Reserved

Hany Mahmoud,1 Hatem Ammar,1 Amr El Rashidy,2 Amal H Ali,3 Hesham M Hefny,4 Amr Mounir1 1Sohag Faculty of Medicine, Ophthalmology Department, Sohag University, Sohag, Egypt; 2Tropical Medicine, Sohag Tropical Medicine Hospital, Sohag, Egypt; 3Microbiology and Immunology, Department of Microbiology, Aswan University, Aswan, Egypt; 4Clinical Pathology Department, Sohag University, Sohag, EgyptCorrespondence: Amr MounirSohag Faculty of Medicine, Ophthalmology Department, Sohag University, Almohafza Street, Mailbox: 82511, Sohag City, EgyptTel +201005026170Email dramrmonir@yahoo.comPurpose: To assess SARS-CoV-2 virus in conjunctival tears and secretions of positive confirmed COVID-19 patients.Methods: A case series study that included 28 positive COVID-19 patients confirmed with nasopharyngeal swab in the period 18– 28 May 2020 at Sohag Tropical Medicine Hospital. Tears and conjunctival secretions of these confirmed positive cases were collected with disposable sampling swabs at interval of 3 days after admission due to respiratory symptoms. They were examined for the presence of SARS-CoV-2 by reverse transcription-polymerase chain reaction (RT‐PCR) assay.Results: Thirteen (46.43%) patients were stable, 4 (14.28%) patients suffered from dyspnea, 3 (10.72%) patients suffered from high fever, 5 (17.85%) patients suffered from cough, and 3 (10.72%) patients were on mechanical ventilation. Ten (35.71%) patients suffered from conjunctivitis. Tear and conjunctival swabs were positive in 8 (28.57%) patients, while other patients’ swabs were negative (71.43%). Out of 10 patients with conjunctival manifestations, 3 patients had SARS-CoV-2 in their conjunctiva using (RT‐PCR) test. Out of the 18 patients with no conjunctival manifestations, 5 patients had positive SARS-CoV-2 in their conjunctiva using (RT‐PCR) test.Conclusion: The SARS-CoV-2 virus could be found in tears and conjunctival secretions in SARS-CoV-2 patients with or without conjunctivitis.Keywords: SARS-CoV-2, conjunctiva, conjunctival secretions, tears, swab, RT‐PCR

Objective: The most widely used diagnostic technique for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is real-time reverse transcriptase-polymerase chain reaction (RT-PCR). It can be done on different samples: nasopharyngeal swabs (NPS) or oropharyngeal swabs (OPS), and self-collected saliva. However, negative findings do not rule out infection. Methods: A review was conceived to discuss advantages and limitations of the available diagnostic modalities for nonserologic diagnosis of SARS-CoV-2 based on RT-PCR; the article also proposes some practical suggestions to improve diagnostic reliability. Results: A total of 16 papers (corresponding to 452 patients) of the 56 initially identified were included. Most of the papers describe findings from different samples obtained in limited case series; comparative studies are missing. Conclusions: Diagnostic accuracy of NPS and OPS is suboptimal and the risk of contaminated aerosol dispersal is not negligible. The SARS-CoV-2 RNA can be found in self-collected saliva specimens of many infected patients within 7 to 10 days after symptom onset. There is an urgent need for comparative trials to define the diagnostic modality of choice. Adequate education and training of health care personnel is mandatory.

Automatic flushing of milking clusters between milking events is a control measure aimed at reducing transmission of mastitis pathogens from infectious milk to a subsequently milked cow. We evaluated the effect of flushing with cold water and flushing with water containing peracetic acid (PAA) on the concentration of Staphylococcus aureus in teat cup liners. Thirty-two clusters in a swing-over milking parlor (Dairymaster, Causeway, Ireland) were subjected to a simulated milking with S. aureus–contaminated milk. Sixteen clusters were not flushed (controls), whereas 8 clusters were flushed with cold water (966 ± 32 mL) and 8 clusters were flushed with water containing PAA (200 mL/mL). A random teat cup in each cluster was sampled by rinsing with a phosphate buffer. Teat cup samples were cultured on the day following collection on Baird-Parker plates to determine the concentration of S. aureus. In teat cup samples from control clusters, the mean concentration of S. aureus was 2.8 × 105 cfu/mL. The concentration of S. aureus was zero in teat cup samples from clusters flushed with cold water. In teat cup samples from clusters flushed with water containing PAA, the concentration of S. aureus was in general reduced compared with control clusters, but S. aureus was not removed completely. However, the automatic cluster flushing did not function properly when clusters were flushed with water containing PAA; thus, results reflected the effect of inadequate function rather than the effect of adding disinfectant to the flushing water. Before the main study, we conducted a pilot study to evaluate whether teat cup sampling with swabs and sample analysis with quantitative PCR were appropriate methods for the main study. Specifically, we evaluated the effect of swab sample mass on detection of S. aureus by quantitative PCR in the laboratory, Further, we compared PCR and bacterial culture on detection of S. aureus in a suspension following disinfection of the suspension with PAA. We sampled 20 identical S. aureus suspensions for culture and PCR by swabs before and after disinfection with PAA. Swab sample mass was determined by differential weighing and contributed to 46% of the variation observed in detection of S. aureus by PCR. Following disinfection with PAA, S. aureus remained detectable by PCR, although culturability ceased. Based on these results, we sampled teat cups in the main study with a buffer rinse and quantified S. aureus in the samples by bacterial culture. We concluded that automatic cluster flushing with cold water was effective in removing S. aureus from teat cup liners and that addition of PAA was therefore not necessary.

Objectives: Cleaning validation is the procedure used to ensure that the cleaning process has eliminated the residues of drug substance from on the equipment surface after manufacture. A simple, sensitive, robust, and accurate high performance liquid chromatographic method was developed for the quantitative estimation of dipyridamole in swab samples obtained from the equipment surface after the manufacture of dipyridamole modified release capsules. Materials and Methods: The method was developed by using a Hypersil BDS C18 (150×4.6 mm, 5 μm) column with mobile phase containing a mixture of buffer (potassium dihydrogen phosphate buffer, pH 7.0±0.05) and methanol in the ratio of 30:70 v/v. Flow rate was 1.5 mL/min, column temperature was 45°C, and injection volume was 5 μL. Results: The method was validated and a specificity study was conducted to prove that there was no interference from blank and swab blank at the retention time of dipyridamole. The limit of detection and limit of quantification (LOQ) were established by using a series of linearity solutions and were found to be 0.041 μg/mL and 0.124 μg/mL, respectively. The method precision at the LOQ level was 8.6% relative standard deviation (RSD), method precision was 0.2% RSD, and ruggedness was 0.3% RSD. The method was accurate from the concentration of 0.13 μg/mL to 21.80 μg/mL and the recovery results met the acceptance criteria. The linearity of the method was found from 0.12 μg/mL to 20.14 μg/mL and the r2 value was 0.997. The robustness for the flow rate, wavelength, column temperature, buffer pH, and mobile phase ratio variations was tested, and all the system suitability parameters were met. Conclusion: The method validation was performed as per the regulatory requirements and guidelines. The validation parameters met the acceptance criteria and the proposed method can be applied for the intended routine swab analysis.

Background Buccal swab sampling constitutes an attractive noninvasive alternative to blood drawings for antibody serostatus assays. Here we describe a method to determine the cytomegalovirus immunoglobulin G (CMV IgG) serostatus from dried buccal swab samples. Methods Upon solubilization, CMV IgG is determined by an ELISA assay specifically adapted to cope with low IgG concentrations. The derived CMV titer is normalized against the total protein concentration to adjust for incorrectly or less efficiently sampled buccal swabs. Assay parameters were optimized on a set of 713 samples. Results Validation with 1784 samples revealed distinct results for > 80% of samples with 98.6% specificity and 99.1% sensitivity. Based on the analysis of 1.2 million samples we derived age- and sex-stratified CMV prevalence statistics for Germany, Poland, United Kingdom, and Chile. To confirm accuracy of the assay in routine operation, the CMV status of 6518 donors was reassessed by independent laboratories based on conventional blood samples revealing 96.9% specificity and 97.4% sensitivity. Conclusions The assay accurately delivers the CMV IgG serostatus from dried buccal swab samples for > 80% of the participants. Thereby it provides a noninvasive alternative to plasma-based CMV monitoring for nondiagnostic purposes such as hematopoietic stem cell transplantation donor screening or population studies., We developed an assay to determine the CMV IgG status based on dried buccal swab samples. Assay validation on a set of 1784 samples revealed 99% sensitivity and specificity. We describe CMV prevalence statistics for Germany, Poland, United Kingdom, and Chile.

A swab is a tool for obtaining buccal DNA from buccal mucus for biological analysis. The acquisition of a sufficient amount and high quality of DNA is an important factor in determining the accuracy of a diagnosis. A microneedle swab (MN swab) was developed to obtain more oral mucosal tissues non-invasively. Eight types of MN swabs were prepared with varying combinations of patterns (zigzag or straight), number of MNs, intervals of MNs, and sharpness of tips. When MN swab was applied up to 10 times, the tissue amount and DNA yield increased compared to commercial swabs. A zigzag pattern of microneedles was found to be more efficient than a straight pattern and increasing the number of microneedles in an array increased the DNA yield. The MN swab collected about twice the DNA compared to the commercial swab. In an in vivo test using mini pigs, the lower cycle threshold values of mucosal samples collected with MN swabs compared to samples collected with commercial swabs indicated that a greater amount of DNA was collected for SNP genotyping. A polymer MN swab is easy to manufacture by a single molding process, and it has a greater sampling capacity than existing commercial swabs.

Objectives: The aim of this study was to evaluate the possible relationship between cultural specimens and preterm birth in women admitted for threatened preterm labor. Preterm birth is the leading cause of neonatal mortality and antenatal hospitalization; several risk factors including intrauterine infections have been identified, but its real causes remain poorly understood. Design: This is a retrospective, multicenter, cohort study including 250 women admitted for threatened preterm labor. Methods, Participants/Materials, Setting: All women admitted for threatened preterm labor, i.e., presenting with cervical changes and uterine activity before 37 weeks at the obstetrics unit of the hospitals of Modena, Monza, Carate, and Vimercate were included in the study. We excluded twin pregnancies and cases with preterm premature rupture of membranes at admission. Data about maternal history, pregnancy complications, cervical length, vaginal swabs, and urine culture at admission and gestational age at delivery were collected from clinical records in order to compare the incidence of preterm birth according to some known risk factors, cervical length, and microbiological test at admission. Results: 250 women were included in the study; preterm birth at less than 37 weeks occurred in 44.4% women admitted for threatened preterm labor. The incidence of preterm birth was not different between those with a positive or a negative vaginal swab (48.3 vs. 38.4%, p = 0.22) or positive versus negative urine culture (31.8 vs. 42.1%, p = 0.23) at admission. A shorter cervical length at admission was found in women with subsequent preterm birth (17 vs. 19.5 mm, p = 0.03). Cervical length p = 0.039) predicted the risk of preterm birth. Furthermore, only the history of a previous preterm birth (p = 0.02) and a previous uterine curettage (p = 0.045) was associated with preterm birth. Limitations: The observational and retrospective nature of the study and its small sample size are important limitations of the study. Moreover, women were not systematically or randomly assigned to the screening for vaginal or urinary infections. Conclusions: There is no evidence that the search for vaginal or urinary infections in women admitted for threatened preterm labor is helpful to identify those at increased risk of preterm birth. Although several studies have explored the role of screening for bacterial vaginosis in asymptomatic women and some studies evaluated vaginal or urinary infections in women with preterm birth, none of them focused on the possible role of microbiological specimens as a predictive tool in women admitted for threatened PTL. No association was found in our study, but prospective randomized controlled trials are required to confirm the results of this observation.

Nasopharyngeal swabs (NPS) are considered the gold standard for SARS-CoV-2 testing but are technically challenging to perform and associated with discomfort. Alternative specimens for viral testing, such as oropharyngeal swabs (OPS) and nasal swabs, may be preferable, but strong evidence regarding their diagnostic sensitivity for SARS-CoV-2 testing is still missing. We conducted a head-to-head prospective study to compare the sensitivity of NPS, OPS and nasal swabs specimens for SARS-CoV-2 molecular testing. Adults with an initial positive SARS-CoV-2 test were invited to participate. All participants had OPS, NPS and nasal swab performed by an otorhinolaryngologist. We included 51 confirmed SARS-CoV-2-positive participants in the study. The sensitivity was highest for OPS at 94.1% (95% CI, 87 to 100%) compared to NPS at 92.5% (95% CI, 85 to 99%) (p = 1.00) and lowest for nasal swabs at 82.4% (95% CI, 72 to 93%) (p = 0.07). Combined OPS/NPS was detected in 100% of cases, while the combined OPS/nasal swab increased the sensitivity significantly to 96.1% (95% CI, 90 to 100%) compared to that of the nasal swab alone (p = 0.03). The mean Ct value for NPS was 24.98 compared to 26.63 for OPS (p = 0.084) and 30.60 for nasal swab (p = 0.002). OPS achieved a sensitivity comparable to NPS and should be considered an equivalent alternative for SARS-CoV-2 testing.

Brucellosis is a worldwide zoonosis caused by bacteria from the genus Brucella. Once established, it is very hard to eradicate this disease, since it contaminates animals, the environment, and humans, causing problems for veterinary and public health as well as wildlife protection programs. Swabs are used for sampling in bacteriological and/or molecular diagnostics, from seropositive animals with disease symptoms, from genitalia or tissue lesions, as well as from contaminated environments. The aim of this study was to compare main of the commercially used swab types for sampling and diagnostics of Brucella spp. and determine the optimal storage conditions and time frame for testing. To achieve this, we tested bacterial and molecular methods for detection of Brucella abortus, Brucella melitensis, and Brucella suis using nine swab types, all with different tip materials, treated immediately after spiking, after 72 h at +4°C, and after 72 h at -20°C. Flocked swabs showed the highest capacity to preserve bacterial viability and DNA quality, regardless the storage conditions. Flocked swabs immersed in a protective medium provided the best conditions for Brucella survival in all three storage conditions. At the same time, the efficacy of quantitative PCR (qPCR) detection for all swabs, including the positive control, was above 50%, irrespective of the storage conditions, while bacterial survival was significantly lowered when swabs were kept at +4°C or -20°C for 72 h (48.2% and 27.5%, respectively). Compared to the positive control and other types, the flocked swabs maintained higher reproducibility regarding their capacity to preserve live bacteria in all three storage conditions. IMPORTANCE In order to protect public and veterinary health from highly zoonotic bacteria such as members of the genus Brucella and prevent their dissemination into the environment, direct diagnostics are of utmost importance. However, in addition to the highly specific diagnostic tests, the sampling methods, time necessary for specimens to reach the laboratories, and transport conditions are important factors to consider in order to increase the sensitivity of performed tests, especially bacterial culturing and qPCR. This paper shows how different swab types and storage conditions influence classical bacteriological diagnostics of the most prevalent Brucella species - B. melitensis, B. abortus, and B. suis - but have little impact on molecular methods. The presented results highlight (i) the choice of swab regarding the storage and transport conditions, (ii) the importance of immediate swab treatment upon sampling, and (iii) that molecular methods do not depend on storage conditions, unlike classical bacteriological isolation.

Environmental monitoring in public spaces can be used to identify surfaces contaminated by persons with coronavirus disease 2019 (COVID-19) and inform appropriate infection mitigation responses. Research groups have reported detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on surfaces days or weeks after the virus has been deposited, making it difficult to estimate when an infected individual may have shed virus onto a SARS-CoV-2-positive surface, which in turn complicates the process of establishing effective quarantine measures. In this study, we determined that reverse transcription-quantitative PCR (RT-qPCR) detection of viral RNA from heat-inactivated particles experiences minimal decay over 7 days of monitoring on eight out of nine surfaces tested. The properties of the studied surfaces result in RT-qPCR signatures that can be segregated into two material categories, rough and smooth, where smooth surfaces have a lower limit of detection. RT-qPCR signal intensity (average quantification cycle [Cq]) can be correlated with surface viral load using only one linear regression model per material category. The same experiment was performed with untreated viral particles on one surface from each category, with essentially identical results. The stability of RT-qPCR viral signal demonstrates the need to clean monitored surfaces after sampling to establish temporal resolution. Additionally, these findings can be used to minimize the number of materials and time points tested and allow for the use of heat-inactivated viral particles when optimizing environmental monitoring methods. IMPORTANCE Environmental monitoring is an important tool for public health surveillance, particularly in settings with low rates of diagnostic testing. Time between sampling public environments, such as hospitals or schools, and notifying stakeholders of the results should be minimal, allowing decisions to be made toward containing outbreaks of coronavirus disease 2019 (COVID-19). The Safer At School Early Alert program (SASEA) (https://saseasystem.org/), a large-scale environmental monitoring effort in elementary school and child care settings, has processed >13,000 surface samples for SARS-CoV-2, detecting viral signals from 574 samples. However, consecutive detection events necessitated the present study to establish appropriate response practices around persistent viral signals on classroom surfaces. Other research groups and clinical labs developing environmental monitoring methods may need to establish their own correlation between RT-qPCR results and viral load, but this work provides evidence justifying simplified experimental designs, like reduced testing materials and the use of heat-inactivated viral particles.

Since the beginning of 2020, the betacoronavirus SARS-CoV-2 is causing a global pandemic of an acute respiratory disease termed COVID-19. The diagnostics of the novel disease is primarily based on direct virus detection by RT-PCR, however, the availability of test kits may become a major bottleneck, when millions of tests are performed per week. To increase the flexibility of SARS-CoV-2 diagnostics, three real-time RT-PCR assays listed on the homepage of the World Health Organization were selected and investigated regarding their compatibility with three different RT-PCR kits. Furthermore, the reaction volume of the PCR chemistry was reduced up to half of the original protocol to make the individual reactions more cost- and resource-effective. When testing dilution series of culture-grown virus, nearly identical quantification cycle values (Cq) were obtained for all RT-PCR assay/chemistry combinations. Regarding the SARS-CoV-2 detection in clinical samples, agreeing results were obtained for all combinations for virus negative specimens and swabs containing high to medium viral genome loads. In cases of very low SARS-CoV-2 genome loads (Cq &gt, 36), inconsistent results were observed, with some test runs scoring negative and some positive. However, no preference of a specific target within the viral genome (E, RdRp, or N) or of a certain chemistry was seen. In summary, a reduction of the reaction volume and the type of PCR chemistry did not influence the PCR sensitivity.

This work verified the use of cytological diagnosis, as a method of identification of disorders in dogs and cats domiciled in the municipality of Barra-BA seen at the University Veterinary Hospital (HVU) of the Federal University of Western Bahia (UFOB). The study was conducted from the analysis of cytological samples related to clinical cases seen in the years 2018 and 2019. A total of 711 animals were seen, of these counted 105 (101 canines and 4 felines - 59 females and 46 males) requests for the cytological examination. Most of the animals (28.57%) were 6 to 10 years old, with the prevalence of No Defined Breed animals (62.38%). The inflammatory processes were diagnosed in 43.80% of the cases, identified as having infectious cause in 86.90% (30% by Leishmania spp., 27.5% bacterial infections, 27.5% by the yeast Malassezia spp. and other 15% by association of this fungus with bacteria). Inflammatory processes of non-infectious origin were recorded in 13.10% cases (84% infiltrated by inflammatory cells and 16% as lick dermatitis). Non-inflammatory processes were observed in 19.05% of the samples, 95% of which were of neoplastic origin, (63.15% TVT, 21.05% Squamous Cell Carcinoma, 10.05% Adenocarcinoma and 5.30% Trichoblastoma). Among the non-inflammatory and non-neoplastic processes (5%) an epidermal cyst was diagnosed (100%). The applicability of cytological diagnosis in dogs and cats denotes importance since it helps veterinarians in confirming clinical suspicions, allowing the issuance of diagnostic reports, establishment of treatments and epidemiological data that enable the implementation of control measures of diseases. Este estudio verificó el uso del diagnóstico citológico, como método de identificación de trastornos en perros y gatos domiciliados en el municipio de Barra-BA atendidos en el Hospital Veterinario Universitario (HVU) de la Universidad Federal del Oeste de Bahía (UFOB). El estudio se realizó a partir del análisis de muestras citológicas relacionadas con casos clínicos atendidos en los años 2018 y 2019. Se atendieron 711 animales, de los cuales se contabilizaron 105 (101 caninos y 4 felinos - 59 hembras y 46 machos) solicitudes de examen citológico. La mayoría de los animales (28,57%) tenían entre 6 y 10 años, prevaleciendo los animales Sin Raza Definida (62,38%). Los procesos inflamatorios se diagnosticaron en el 43,80% de los casos, identificándose como causa infecciosa en el 86,90% (30% por Leishmania spp., 27,5% infecciones bacterianas, 27,5% por la levadura Malassezia spp. y otro 15% por asociación de este hongo con bacterias). Los procesos inflamatorios de origen no infeccioso se registraron en el 13,10% de los casos (el 84% infiltrados por células inflamatorias y el 16% como dermatitis por lamido). Se observaron procesos no inflamatorios en el 19,05% de las muestras, de las cuales el 95% eran de origen neoplásico, (63,15% TVT, 21,05% Carcinoma de células escamosas, 10,05% Adenocarcinoma y 5,30% Tricoblastoma). Entre los procesos no inflamatorios y no neoplásicos (5%) se diagnosticó un quiste epidérmico (100%). La aplicabilidad del diagnóstico citológico en perros y gatos denota importancia una vez, ayudó a los médicos veterinarios en la confirmación de las sospechas clínicas, permitiendo la emisión de informes diagnósticos, establecimiento de tratamientos y datos epidemiológicos que hacen posible la implantación de medidas de control de las enfermidades. Este trabalho verificou a utilização do diagnóstico citológico, como método de identificação de afecções em cães e gatos domiciliados no município de Barra-BA atendidos no Hospital Veterinário Universitário (HVU) da Universidade Federal do Oeste da Bahia (UFOB). O estudo foi realizado a partir da análise de amostras citológicas relativas aos casos clínicos atendidos nos anos de 2018 e 2019. Foram atendidos 711 animais, desses contabilizadas 105 (101 caninos e 4 felinos - 59 fêmeas e 46 machos) solicitações do exame citológico. A maioria dos animais (28,57%) apresentavam de 6 a 10 anos, prevalecendo os animais Sem Raça Definida (62,38%). Os processos inflamatórios foram diagnosticados em 43,80% dos casos, identificados como de causa infecciosa em 86,90% (30% por Leishmania spp., 27,5% infecções bacterianas, 27,5% pela levedura Malassezia spp. e outros 15% por associação deste fungo a bactérias). Os processos inflamatórios de origem não infecciosa foram registrados em 13,10% casos (84% infiltrados de células inflamatórias e 16% como dermatite por lambedura). Observou-se processos não inflamatórios em 19,05% das amostras, sendo 95% de origem neoplásica, (63,15% TVT, 21,05% Carcinoma de Células Escamosas, 10,05% Adenocarcinoma e 5,30% Tricoblastoma). Já entre os processos não inflamatórios e não neoplásicos (5%) diagnosticou-se um cisto epidérmico (100%). A aplicabilidade do diagnóstico citológico em cães e gatos denota importância uma vez que, auxiliou médicos veterinários na confirmação de suspeitas clínicas, permitindo a emissão de laudos diagnósticos, estabelecimento de tratamentos e dados epidemiológicos que possibilitam a implantação de medidas de controle das enfermidades.

Introduction in the COVID-19 era, the debate around the risk of contagion at school, is intense in Italy. The Department of Welfare and Wealth of Florence promoted a screening campaign with antigen rapid tests for all the students and school personnel. The aim of this study is to assess the SARS-Cov2 circulation in the school setting by means of a mass screening conducted in every primary and middle school of Florence. Methods All the students attending primary and middle schools of Florence and the school personnel were asked to take part. The campaign started on 16th November 2020 and was completed on 12th February 2021. If the antigen rapid test resulted positive, a molecular test was provided to confirm the result. Results 18,414 subjects were tested with 15,233 students (82.7%) and 3,181 members of the school personnel (17.3%). Only in 27 cases (0.15%) the rapid test gave a positive result. Moreover, only 14 of the 27 positive rapid tests were confirmed as positive by the molecular test. These results show a very low number of SARS-CoV-2 cases among the people tested (0.08% of the total). Conclusions These results show that the spread of SARS-CoV-2 infection at school, during the months of the screening and with the respect of strict preventive measures was low.

Background Differential diagnosis of interstitial lung diseases (ILDs) during the COVID-19 pandemic is difficult, due to similarities in clinical and radiological presentation between COVID-19 and other ILDs on the one hand, and frequent false-negative swab results on the other. We describe a rare form of interstitial and organizing pneumonia resembling COVID-19, emphasizing some key aspects to focus on to get the right diagnosis and treat the patient properly. Case presentation A 76-year-old man presented with short breath and dry cough in the midst of the COVID-19 outbreak. He showed bilateral crackles and interstitial-alveolar opacities on X-ray, corresponding on computed tomography (CT) to extensive consolidations with air bronchograms, surrounded by ground glass opacities (GGO). Although his throat-and-nasopharyngeal swab tested negative, the picture was overall compatible with COVID-19. On the other hand, he showed subacute, rather than hyperacute, clinical onset; few and stable parenchymal consolidations, rather than patchy and rapidly evolving GGO; pleural and pericardial thickening, pleural effusion, and lymph node enlargement, usually absent in COVID-19; and peripheral eosinophilia, rather than lymphopenia, suggestive of hypersensitivity. In the past year, he had been taking amiodarone for a history of ventricular ectopic beats. CT scans, in fact, highlighted hyperattenuation areas suggestive of amiodarone pulmonary accumulation and toxicity. Bronchoalveolar lavage fluid (BALF) investigation confirmed the absence of coronavirus genome in the lower respiratory tract; conversely, high numbers of foamy macrophages, eosinophils, and cytotoxic T lymphocytes with low CD4/CD8 T-cell ratio were detected, confirming the hypothesis of amiodarone-induced cryptogenic organizing pneumonia. Timely discontinuation of amiodarone and initiation of steroid therapy led to resolution of respiratory symptoms, systemic inflammation, and radiographic opacities. Conclusions A comprehensive analysis of medical and pharmacological history, clinical onset, radiologic details, and peripheral and BALF cellularity, is required for a correct differential diagnosis and management of ILDs in the COVID-19 era.

Background: Swabbing of implants removed from potentially infected sites represents a time saving and ubiquitously applicable alternative to sonication approaches. The latter bears an elevated risk of processing related contaminations due to the high number of handling steps. Since biofilms are usually invisible to the naked eye, adequate swabbing relies on the chance of hitting the colonized area on the implant. A targeted directed swabbing approach could overcome this detriment. Method: Three dyes were tested at different concentrations for their toxicity on biofilm-associated cells of S. epidermidis, the species most frequently identified as a causative agent of implant-associated infections. Results: Malachite green (0.2%) delivered the highest bacterial recovery rates combined with the best results in biofilm visualization. Its suitability for diagnostic approaches was demonstrated for smooth and rough implant surfaces. Biofilm-covered areas were successfully visualized. Conclusion: Subsequent targeted swab-sampling resulted in a significantly increased bacterial recovery rate compared to a dye-free “random swabbing” diagnostic approach.

Chronic wounds are a prominent health concern affecting 0.2% of individuals in the Western population. Microbial colonization and the consequent infection contribute significantly to the healing process. We have compared two methods, cultivation and 16S amplicon sequencing (16S-AS), for the characterization of bacterial populations in both swabs and biopsy tissues obtained from 45 chronic wounds. Using cultivation approach, we detected a total of 39 bacterial species, on average 2.89 per sample (SD = 1.93), compared to 5.9 (SD = 7.1) operational taxonomic units per sample obtained with 16S-AS. The concordance in detected bacteria between swab and biopsy specimens obtained from the same CWs was greater when using cultivation (58.4%) as compared to 16S-AS (25%). In the entire group of 45 biopsy samples concordance in detected bacterial genera between 16S-AS and cultivation-based approach was 36.4% and in swab samples 28.7%. Sequencing proved advantageous in comparison to the cultivation mainly in case of highly diverse microbial communities, where we could additionally detect numerous obligate and facultative anaerobic bacteria from genera Anaerococcus, Finegoldia, Porphyromonas, Morganella, and Providencia. Comparing swabs and biopsy tissues we concluded, that neither sampling method shows significant advantage over the other regardless of the method used (16S-AS or cultivation). In this study, chronic wound microbiota could be distributed into three groups based on the bacterial community diversity. The chronic wound surface area was positively correlated with bacterial diversity in swab specimens but not in biopsy tissues. Larger chronic wound surface area was also associated with the presence of Pseudomonas in both biopsy and swab specimens. The presence of Corynebacterium species at the initial visit was the microbial marker most predictive of the unfavorable clinical outcome after one-year follow-up visit.

Background: Vaginal swabs have been traditionally used for the diagnosis of bacterial vaginosis (BV). Currently, there are limited studies that have investigated the use of other sample types other than vaginal swabs for the detection of BV from South African populations. This study investigated whether urine can be used for the detection of BV-associated microorganisms in South African pregnant women. Methods: One-hundred self-collected vaginal swabs and urine samples were obtained from women presenting for antenatal care at King Edward VIII Hospital in Durban. The BD MAX™ vaginal panel assay was used for diagnosing BV and droplet digital polymerase chain reaction was used to quantify Gardnerella vaginalis, Prevotella bivia, Atopobium vaginae and Lactobacillus crispatus . The absolute counts were determined on the QX200 Droplet Reader (Bio-Rad) using the QuantaSoft Software. Data analysis was performed with statistical computing software called R, version 3.6.1. Results: Median copy numbers obtained for G. vaginalis and P. bivia across urine and swabs in BV-positive samples were not significantly different ( p = 0.134 and p = 0.652, respectively). This was confirmed by the correlation analysis that showed a good correlation between the two sample types ( G. vaginalis [ r = 0.63] and P. bivia [ r = 0.50]). However, the data obtained for A. vaginae differed, and a weak correlation between urine and swabs was observed ( r = 0.21). Bacterial vaginosis-negative samples had no significant difference in median copy numbers for L. crispatus across the urine and swabs ( p = 0.062), and a good correlation between the sample types was noted ( r = 0.71). Conclusion: This study highlights the appropriateness of urine for the detection of microorganisms associated with BV.

Candida is a commensal yeast. It can be infective when the host’s defense mechanism is weakened, as in the case of squamous cell carcinoma patients. We aimed to evaluate the prevalence and clinical mycological manifestation of candidiasis in 150 cancer cases comprised of preoperative and post-operative (with or without radiotherapy) upper aerodigestive squamous cell carcinoma. A total of 150 patients suffering from squamous cell carcinoma of the Upper Aero-Digestive Tract (UADT) were divided into preoperative (n = 48), post-operative without radiotherapy (n = 29) and post-operative with radiotherapy (n = 73). Samples were collected using cotton swabs and cultured. Candida species were identified according to color pigmentation on Candida Differential Agar (CDA) plate. The clinico-mycological association of patients was evaluated by the chi-square test, and 98 out of 150 patients showed the presence of various Candida species. The major species isolated was Candida albicans (53%), followed by Candida tropicalis (16%). There was a significant statistical difference between patients who showed mycological associations and patients who did not have any such association (p = 0.0008). The prevalence of oral candidiasis was found to be 65.33% among total cases of upper aero-digestive squamous cell carcinoma. Chronic erythematous cases of candidiasis were mainly seen in preoperative squamous cell carcinoma cases, whereas the acute erythematous type of candidiasis was mainly seen in post-operative cases who received radiotherapy. The clinicomycological assessment can help to correlate the signs and symptoms with the presence of candidiasis in upper aerodigestive squamous cell carcinoma patients. Meticulous testing and examination can help in the early detection of candidiasis. Future studies are needed to develop advance scientific preventive strategies for high-risk cases.

Hany Mahmoud,1 Ahmed Hamody,2 Hesham M Hefny,3 Dalia Tohamy,4 Islam Awny5 1Department of Ophthalmology, Faculty of Medicine, Sohag University, Sohag, Egypt; 2Anesthesia Department, Sohag University, Sohag, Egypt; 3Clinical Pathology Department, Sohag University, Sohag, Egypt; 4Ophthalmology Department, Assiut University, Assiut, Egypt; 5Department of Ophthalmology, Sohag University, Sohag, EgyptCorrespondence: Hany MahmoudDepartment of Ophthalmology, Faculty of Medicine, Sohag University, EgyptTel +20 1024368111Email drhanymahmoud@gmail.comPurpose: To assess the presence of anti-SARS-CoV-2 IgA in the conjunctival secretions of confirmed COVID-19 patients by nasopharyngeal swabs and correlate its presence with the severity of the disease, patient’s age, sex and ocular symptoms.Methods: This study included 44 positive COVID-19 patients confirmed with nasopharyngeal swabs during the period 17– 28 February 2021 at Sohag Tropical Medicine Hospital. Tears and conjunctival secretions were examined for the presence of anti-SARS-CoV-2 IgA.Results: While non-reactive results are strongly correlated to low titre and vice versa, severity showed significant correlation with neither IgA reactivity nor titre. Meanwhile, IgA reactivity did not show significant correlation with either age or sex. The reactivity and IgA titre are correlated with ocular symptoms.Conclusion: The anti-SARS-CoV-2 IgA could be found in ocular secretions in SARS-CoV-2 patients. There is no correlation with age or sex or severity of the disease; however, they are correlated with ocular symptoms.Keywords: anti-SARS-CoV-2 IgA, ocular, secretions, swab

The epidemic of a novel coronavirus, named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still gradually spreading worldwide. Real-time fluorescence quantitative reverse transcriptase polymerase chain reaction (reverse transcriptase-polymerase chain reaction, RT-PCR), run in biological samples, is the gold standard method for confirmation of infection. In Italy, two consecutive negative results in oropharyngeal and nasopharyngeal swabs allow patients’ discharging from the hospital or quarantine interruption. Since several recent studies reported false-negative swab results, we present a peculiar double negative case then become positive after a new contact with her boyfriend. Additionally, we discuss the risk derived from SARS-CoV-2 asymptomatic spreader’s confinement suspension., Journal of Preventive Medicine and Hygiene, Vol. 62 No. 1 (2021): 2021621

In light of the present pandemic of novel coronavirus disease 2019 (COVID-19) and the unprecedented high demand for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing worldwide, there are shortages of established specimen collection devices for respiratory viral testing for diagnostic microbiology laboratories. This creates the need to validate unverified collection devices from manufacturers that may not be a registered supplier for medical devices., In light of the present pandemic of novel coronavirus disease 2019 (COVID-19) and the unprecedented high demand for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing worldwide, there are shortages of established specimen collection devices for respiratory viral testing for diagnostic microbiology laboratories. This creates the need to validate unverified collection devices from manufacturers that may not be a registered supplier for medical devices. As clinical laboratories do not routinely perform quality control of established collection devices, there is a need to have a systematic, robust approach to the assessment of substitute unregistered collection swabs and viral transport media (VTM). A discussion of the aspects requiring consideration when determining the suitability and implementation of new collection devices is presented. These specific assessment criteria include an inspection of device integrity, determination of swab and VTM sterility and in vitro performance, VTM stability, and examination of the clinical performance of the device. This method was used in a front-line medical microbiology laboratory on swabs and VTM from an unregistered manufacturer, with suboptimal results that precluded implementation. As the pandemic continues, it will be important for diagnostic laboratories to adopt a flexible and streamlined approach to maintaining adequate supply chains for testing reagents and materials.

Background: Swabbing of implants removed from potentially infected sites represents a time saving and ubiquitously applicable alternative to sonication approaches. The latter bears an elevated risk of processing related contaminations due to the high number of handling steps. Since biofilms are usually invisible to the naked eye, adequate swabbing relies on the chance of hitting the colonized area on the implant. A targeted directed swabbing approach could overcome this detriment. Method: Three dyes were tested at different concentrations for their toxicity on biofilm-associated cells of S. epidermidis, the species most frequently identified as a causative agent of implant-associated infections. Results: Malachite green (0.2%) delivered the highest bacterial recovery rates combined with the best results in biofilm visualization. Its suitability for diagnostic approaches was demonstrated for smooth and rough implant surfaces. Biofilm-covered areas were successfully visualized. Conclusion: Subsequent targeted swab-sampling resulted in a significantly increased bacterial recovery rate compared to a dye-free “random swabbing” diagnostic approach.

A cleaning validation for a family of compounds utilizing swab sampling and rinse solution procedures, and high performance liquid chromatography for separation and detection of the analytes was performed.Effective parameters on recovery including sampling method, swab characteristics, solvent, swabbing technique, and material substance of product contact surfaces within the manufacturing equipment for swab and rinse sampling method, quantitative cleaning verification method, and active pharmaceutical ingredient (API) level and nature have been studied.The limit of detection and the limit of quantitation for the HPLC method were determined to be 0.0198 µg/mL, and 0.0495 µg/mL of the analyte, respectively. The linearity on replicate injections of the standard prepared in the range of 0.78, 1.55, 3.1, and 6.2 µg/mL, and relative standard deviation (R.S.D.) found to be 1.2, 1.0, 0.9, and 0.6, respectively with correlation coefficient of R2 = 0.9999. Recovery coverage for each type of surface was acceptable, ranging from 63.88% for swab sampling of stainless steel to 97.85% for rinse sampling of PVC. The acceptance criteria for precision on replicate injections of the analyte prepared in three concentration levels covering the specified range of 50, 100, and 200% was successfully accomplished R.S.D. lower than 15% for recovery results.Thus, choosing the appropriate sampling method, swab type, and surface condition can affect and increase recovery rate determination efficiency.

Swabbing tests have proved to be an effective method of diagnosis for a wide range of diseases. Potential occupational health hazards and reliance on healthcare workers during traditional swabbing procedures can be mitigated by self-administered swabs. Hence, we report possible methods to apply closed kinematic chain theory to develop a self-administered viral swab to collect respiratory specimens. The proposed sensorized swab models utilizing hollow polypropylene tubes possess mechanical compliance, simple construction, and inexpensive components. In detail, the adaptation of the slider-crank mechanism combined with concepts of a deployable telescopic tubular mechanical system is explored through four different oral swab designs. A closed kinematic chain on suitable material to create a developable surface allows the translation of simple two-dimensional motion into more complex multi-dimensional motion. These foldable telescopic straws with multiple kirigami cuts minimize components involved in the system as the characteristics are built directly into the material. Further, it offers a possibility to include soft stretchable sensors for realtime performance monitoring. A variety of features were constructed and tested using the concepts above, including 1) tongue depressor and cough/gag reflex deflector; 2) changing the position and orientation of the oral swab when sample collection is in the process; 3) protective cover for the swabbing bud; 4) a combination of the features mentioned above.

The activity of the SARS-CoV-2 virus has not yet been studied in a post-mortem setting. The absence of these data has led to the prohibition of exposure of infected corpses during burial procedures. Our aim was to assess the virus’s persistence and the possibility of transmission in the post-mortem phase including autopsy staff. The sample group included 29 patients who were admitted to our Covid-19 Centre who died during hospitalisation and the autopsy staff. All the swabs were subjected to a one-step real-time reverse transcription polymerase chain reaction with cycle threshold (Ct) values. Swab collection was performed at 2 h, 4 h, 6 h, 12 h, over 24 since death. The following were the analysis of patients’ swabs: 10 cases were positive 2 h after death; 10 cases positive 4 h after death; 9 cases were found positive 6 h after death; 7 cases positive 12 h after death; 9 cases remained positive 24 h after death. The swabs performed on all the forensic pathologist staff on duty who performed the autopsies were negative. The choice to avoid rituals and the display of corpses before and at the burial procedures given appears cautiously valid due to the persistence of the SARS-CoV-2 virus in the post-mortem period. Although the caution in choosing whether or not to perform an autopsy on infected corpses is acceptable, not to perform autopsies is not biologically supported.

Objective Nose and nasopharyngeal swab is the preferred and worldwide‐accepted method to detect the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) within the nose and nasopharynx. This method may be linked with possible difficulties, such as patient's discomfort or complications. This article shows a pilot study of SARS‐CoV‐2 detection with nasal and nasopharyngeal lavage fluids (level of evidence: 3). Methods Nasal lavage fluid was collected from patients who were submitted to SARS‐CoV‐2 screening test, due to a preceding positive rapid antigen test. A control group was enrolled among health care professionals whose nasopharyngeal swab tested negative. Nasal lavages were performed using isotonic saline solution injected through a nasal fossa. Both lavage fluid and traditional nasopharyngeal swab were analyzed by real‐time (RT) PCR and antigenic test. Results A total of 49 positive subjects were enrolled in the study. Results of the analysis on lavages and nasopharyngeal swabs were concordant for 48 cases, regardless of the antigenic and molecular test performed. RT‐PCR resulted weakly positive at swab in one case and negative at lavage fluid. Among the control group (44 subjects), nasopharyngeal swab and lavage fluid analyses returned a negative result. Sensitivity of the molecular test based on nasal lavage fluid, compared to traditional nasal swab, was 97.7%, specificity was 100%, and accuracy was 98.9%, with high agreement (Cohen's κ, 0.978). Conclusion Nasal and nasopharyngeal lavages resulted to be highly reliable and well tolerated. A larger series is needed to confirm these results. This approach may potentially represent a valid alternative to the traditional swab method in selected cases. Level of Evidence 3.

The diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection requires the detection of viral RNA by reverse transcription–polymerase chain reaction (RT-qPCR) performed mainly using nasopharyngeal swabs. However, this procedure requires separate analysis per each individual, performed in advanced centralized laboratory facilities with specialized medical personnel. In this study, an alternative approach termed “solid waste-based surveillance (SWBS)” was explored, in order to investigate SARS-CoV-2 infection in small communities through the indirect sampling of saliva left on waste. Sampling was performed at 20 different sites in Italy during the second peak of COVID-19. Three swabs were positive for SARS-CoV-2 using a published RT-qPCR protocol targeting the non-structural protein 14 region, and the viral load ranged 4.8 × 103–4.0 × 106 genome copies/swab. Amino acid substitutions already reported in SARS-CoV-2 sequences circulating in Italy (A222V and P521S) were detected in two positive samples. These findings confirmed the effectiveness of SWBS for non-invasive and dynamic SARS-CoV-2 surveillance., Graphical abstract Unlabelled Image

Current diagnostic techniques for the detection of the small hive beetle (SHB), Aethina tumida are limitedly available and not cost effective. More sensitive pragmatic methods are preferred for early detection. To improve diagnostics, we focused on sampling techniques for SHB frass, as an indicator for SHB presence in a honey bee colony. In this study, we successfully tested a novel approach of employing swab sample collection of frass for real-time PCR detection of SHB

Purpose To evaluate the diagnostic reliability and practicability of self-collected oropharyngeal swab samples for the detection of SARS-CoV-2 infection as self-sampling could enable broader testing availability and reduce both personal protective equipment and potential exposure. Methods Hospitalized SARS-CoV-2-infected patients were asked to collect two oropharyngeal swabs (SC-OPS1/2), and an additional oropharyngeal swab was collected by a health care professional (HCP-OPS). SARS-CoV-2 PCR testing for samples from 58 participants was performed, with a 48-h delay in half of the self-collected samples (SC-OPS2). The sensitivity, probability of concordance, and interrater reliability were calculated. Univariate and multivariate analyses were performed to assess predictive factors. Practicability was evaluated through a questionnaire. Results The test sensitivity for HCP-OPS, SC-OPS1, and SC-OPS2 was 88%, 78%, and 77%, respectively. Combining both SC-OPS results increased the estimated sensitivity to 88%. The concordance probability between HCP-OPS and SC-OPS1 was 77.6% and 82.5% between SC-OPS1 and SC-OPS2, respectively. Of the participants, 69% affirmed performing future self-sampling at home, and 34% preferred self-sampling over HCP-guided testing. Participants with both positive HCP-OPS1 and SC-OPS1 indicating no challenges during self-sampling had more differences in viral load levels between HCP-OPS1 and SC-OPS1 than those who indicated challenges. Increasing disease duration and the presence of anti-SARS-CoV-2-IgG correlated with negative test results in self-collected samples of previously confirmed SARS-CoV-2 positive individuals. Conclusion Oropharyngeal self-sampling is an applicable testing approach for SARS-CoV-2 diagnostics. Self-sampling tends to be more effective in early versus late infection and symptom onset, and the collection of two distinct samples is recommended to maintain high test sensitivity.

Background It has been suggested that women admitted for delivery should have universal PCR testing for SARS‐CoV‐2. Yet, the considerable difference in the incidence of COVID‐19 between different geographic regions may affect screening strategies. Therefore, we aimed to compare questionnaire‐based testing versus universal PCR testing for SARS‐CoV‐2 in women admitted for delivery. Methods A prospective cohort study of women admitted for delivery at a single center during a four‐week period (April 22‐May 25, 2020). All women completed a questionnaire about COVID‐19 signs, symptoms, or risk factors, and a nasopharyngeal swab for PCR for SARS‐CoV‐2. Women who were flagged as suspected COVID‐19 by the questionnaire (questionnaire‐positive) were compared with women who were not flagged by the questionnaire (questionnaire‐negative). Results Overall, 446 women were eligible for analysis, of which 54 (12.1%) were questionnaire‐positive. PCR swab detected SARS‐CoV‐2 in four (0.9%) women: 3 of 392 (0.8%) in the questionnaire‐negative group, and 1 of 54 (1.9%) in the questionnaire‐positive group (P = .43), yielding a number needed to screen of 92 (95% CI 62‐177). In 96% of the cases, the PCR results were obtained only in the postpartum period. No positive PCR results were obtained from neonatal testing for SARS‐CoV‐2. The sensitivity of the questionnaire was 75.0%, and the negative predictive value was 99.7%. Conclusions Although the rate of positive PCR results was not significantly different between the groups, the number needed to screen is considerably high. The use of questionnaire‐based PCR testing in areas with low incidence of COVID‐19 allows for a reasonable allocation of resources and is easy to implement.

INTRODUCTION: We describe cytologic and immunohistologic findings in virus transport medium on cases under investigation of SARS-CoV-2 infection. METHODS: Cytologic findings in cases under investigation of SARS-CoV-2 infection from one hundred consecutive nasopharyngeal swab were reviewed. Immunohistochemistry and SARSCoV-2 RT-PCR determination were performed to detect virus. RESULTS: No viral inclusions were noted in squamous cells obtained from virus transport medium. Immunohistochemical study with monoclonal antibody against SARS-CoV-2 viral nucleoprotein showed positivity in squamous cells. No positivity was present in others cellular components. CONCLUSIONS: SARS-CoV-2 predominantly localizes squamous cells in cytology samples of patients with RT-PCR positive determination of SARSCoV-2. The results of the current study support the notion that the nasopharyngeal region is the anatomical station that SARS-CoV-2 infects first, and the infection can lead to the migration of the virus into the lower airways.