Swab Method Research Articles

Effect of Probiotic Lactobacillus Casei on Secretory Immunoglobulin A (S-IgA) Levels in Rats Norvegicus Strain Wistar Post Ovariectomy

Estrogen promotes the growth of Lactobacillus colonies in the vagina, converting glycogen in superficial cells into lactic acid, resulting in a low vaginal pH that inhibits pathogenic bacteria. Post-menopause, Lactobacillus growth declines, leading to thinner secretions, higher vaginal pH, and a weakened immune system. This study investigates the effect of Lactobacillus casei extract on secretory immunoglobulin A (IgA) levels, vaginal acidity, and beneficial bacteria in the vaginal mucosa. An experimental post-test-only control group design was employed with 24 female rats aged 8-10 weeks, weighing 180-220 grams. Following ovariectomy and a 14-day acclimation, the rats were divided into four groups: a control group (K) with no treatment and three treatment groups (P1, P2, P3) receiving Lactobacillus casei extract at doses of 2ml, 2.25ml, and 2.5ml, respectively, administered orally for 14 days. On day 15, vaginal acidity was measured using a swab method, and IgA levels were assessed via ELISA; gram-positive staining was performed for bacterial identification. One-way ANOVA revealed that Lactobacillus casei extract significantly increased IgA levels and reduced vaginal acidity (p = 0.003 and p = 0.000). The reduction in acidity is attributed to Lactobacillus converting glycogen into lactic acid, maintaining vaginal acidity, while S-IgA on the mucosal surface acts as an opsonin and antigen-presenting cell to inhibit pathogenic growth. The study concludes that Lactobacillus casei extract can elevate secretory IgA levels and normalize vaginal pH.

Validation of the Diabetomics CovAB SARS-CoV-2 antibody test in children: comparison with serology.

Recently a study determining the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in unvaccinated children in NJ (Katic et al. 2023. Pediatric Academic Societies Meeting; Washington, D.C. https://2023.pas-meeting.org/searchbyposterbucket.asp?bm=Public+Health+%26+Prevention&t=Public+Health+%26+Prevention&pfp=Track) was conducted using a gum swab method for antibody detection. The Diabetomics CovAB test, which qualitatively identifies antibodies to SARS-CoV-2 spike protein, is a point-of-care, low-cost test, that is easy to administer in children. While this test provides sensitive and specific results in adults [US Food and Drug Administration (FDA). 2022. Center for devices and radiological health. EUA authorized serology test performance. Available from: https://www.fda.gov/medical-devices/covid-19-emergency-use-authorizations-medical-devices/eua-authorized-serology-test-performance], data on its accuracy in children is lacking. As a follow-up to the above-mentioned study, we compared the results of the gum swab test to a serologic antibody test. We found that the gum swab test was inferior to serology but was fairly sensitive and specific with a high positive predictive value. While the test is not ideal for diagnostic purposes in children it can be a valuable tool for public health officials and pediatricians to understand the extent of past health interventions.

Antibacterial Efficacy of Benzalkonium Chloride Gel with Tongue Brush on S. Mutans and L. Acidophilus and Tongue Coating – A Randomized Controlled Trial

Introduction: The tongue microbiota, like other parts of the oral cavity, plays a significant role in the development of dental caries. S. mutans and L. acidophilus species, are associated with the initiation and progression of dental caries.  Aim: To assess the efficacy of benzalkonium Chloride gel along with tongue cleaning aids in the reduction of tongue coating and bacterial count on dorsal surface of the tongue.  Materials and Methods: A double blinded randomized control trial was conducted among 17-25 years old college students. A total of 60 participants were randomly divided into 4 groups according to their use of tongue cleaning aids as follows: Group A, Tongue Brush Alone; Group B, Tongue Brush with Chlorhexidine Mouthwash (Clohex ADS); Group C, Tongue Brush with Chlorhexidine Gel (Hexigel); and Group D, Tongue Brush with Benzalkonium Chloride Gel. The Winkel tongue coating index (WTCI) was used to measure the tongue coating at baseline and at 14th day and the participant’s tongue coatings on dorsal surface were sampled using swab method, and the number of S. mutans and L. acidophilus colonies were counted before and after intervention.  Results: Both the Hexigel group and Benzalkonium chloride gel group reduced both the bacterial load and tongue coating at 14th Day compared to the baseline data.  Conclusion: This study suggests that usage of Tongue brush along with Benzalkonium Chloride gel decreased the tongue coating and the number of bacteria on the dorsal tongue surface.

Sample collecting methods for bacterial community structure analysis of scalp hair: non-invasive swabbing versus intrusive hair shaft cutting

Human skin samples for microbiome analysis are traditionally collected using a non-invasive swabbing method. Here, we compared the differences in bacterial community structures on scalp hair and scalps with samples collected using non-invasive swabbing and cutting/removal of scalp hair in 12 individuals. Hair-related samples, such as hair shafts and hair swabs, had significantly higher alpha diversity than scalp swab samples, whereas there were no significant differences between hair shafts and hair swabs. The relative abundances of the three major phyla and five major operational taxonomic units were not significantly different between the hair shaft and hair swab samples. The principal coordinate analysis plots based on weighted UniFrac distances were grouped into two clusters: samples from hair-related areas and scalp swabs, and there were significant differences only between samples from hair-related areas and scalp swabs. In addition, a weighted UniFrac analysis revealed that the sampling site-based category was a statistical category but not a hair sampling method-based category. These results suggest that scalp hair bacteria collected using non-invasive swab sampling were comparable to those collected cutting/removal of scalp hair.

Integration of surface swab with optical microscopy for detection and quantification of bacterial cells from stainless-steel surfaces.

Swab sampling is a common method for recovering microbes on various environmental surfaces. Its successful application for a specific target depends on the proper swab method and the following detection assay. Herein, we evaluated critical factors influencing surface swab sampling, aiming to achieve the optimal detection and quantification performance of optical detection for bacterial cells on stainless-steel surfaces. Our results showed the recovery rate of Salmonella enterica (SE1045) cells from the 10×10cm2 stainless-steel surface reached up to 92.71±2.19% when using ammonia bicarbonate-moistened polyurethane foam swabs for gentle collection, followed by ultrasound-assisted release in NH4HCO3 solution. Among the six different foam swabs, the Puritan™ Sterile Large Foam Swab contributed the lowest background noise and highest recovery efficiency when integrated with the optical detection assay. Notably, our method exhibited a strong linear relationship (r2=0.9983) between the detected cell numbers and the theoretical number of SE1045 cells seeded on surfaces in the range of 104-107 Colony Forming Units (CFU), with a limit of detection of 7.2×104 CFU 100cm-2. This integration was completed within 2 h, exhibiting the applicable potential in various settings.

Determination of the effects of hand hygiene education given to nursing students in intensive care unit on hand microbiota

Purpose: This study is conducted with the purpose of comparing fourth-year nursing students' hand hygiene practices and beliefs with their hand flora. Additionally, we aim to assess the effectiveness of hand hygiene education in this context. Material and Methods: This research has been conducted using a pre-test, post-test, and control group quasi-experimental design. The Hand Hygiene Application Inventory and the Hand Hygiene Belief Scale administered as pre-tests. Students underwent tape stripping and swab methods to collect samples for their hand flora before any interventions. A post-test was conducted for the experimental group. Results: The hand hygiene beliefs and practices of both groups were similar before training. When the Hand Hygiene Application Inventory and Hand Hygiene Belief Scale scores before and after the training were examined, an increase was observed in the scale scores after the training. In this study, the microorganisms present in the general hand flora were identified simplistically, and the changes were observed after hand hygiene education. Furthermore, the study shed light on the structure of hand flora after education in terms of microbial load. Conclusion: It has been experimentally determined that there is a significant decrease in hand microbiota load and pathogenic groups with hand hygiene education.

Simple tape-stripping method for highly reliable and quantitative analysis of skin microbiome.

The composition of human skin microbiome profoundly impacts host skin health and disease. However, the relationship between skin homeostasis or the development of skin diseases and daily changes in skin microbial composition is poorly understood. Longitudinal samplings at more frequent intervals would address this issue, while conventional sampling methods have technical difficulties, leading to limitations in sampling opportunities. Here, we developed a simple and stable tape-stripping method regardless of the operator's skill. Our method enables skin microbial sampling within 30 seconds and taking multiple skin microbial samples from the same body site. The amount of microbial DNA among multiple sampling sites could be measured within 13.5%. The sequencing results of multiple sampling showed high consistency, Pearson's correlation coefficient between multiple samples of 0.98. Furthermore, these results were comparable to those collected by the conventional swabbing method. These results demonstrate that our tape-stripping method enables simple microbiome collection and highly reliable quantitative skin microbiome analysis. These features of our method would lead to a further understanding of skin disease development or diagnosis of skin conditions in clinical research by increasing the opportunities for microbial sampling.

Exploring the relationship between caffeine metabolism-related CYP1A2 rs762551 polymorphism and team sport athlete status and training adaptations

BackgroundThis study aimed to achieve a dual objective: to compare the frequencies of CYP1A2 rs762551 genotypes between team sport athletes and a control group, and to determine the association between the rs762551 polymorphism and changes in physical performance after a six-week training program among elite basketball players.MethodsThe study encompassed an analysis of 504 individuals, comprising 320 athletes and 184 controls. For the Turkish cohort, DNA was isolated using the buccal swab method, and genotyping was conducted using the KASP technique. Performance assessments included the Yo-Yo IR2 and 30 m sprint tests. For Russian participants, DNA samples were extracted from peripheral blood, a commercial kit was used for DNA extraction, and genotyping of the rs762551 polymorphism was conducted using DNA microarray.ResultNotably, a statistically significant linear decline in the prevalence of the CC genotype was observed with ascending levels of athletic achievement within team sports (sub-elite: 18.0%, elite: 8.2%, highly elite: 0%; p = 0.001). Additionally, the CA genotype was the most prevalent genotype in the highly elite group compared to controls (80.0% vs. 45.1%, p = 0.048). Furthermore, statistically significant improvements in Yo-Yo IR2 performance were noted exclusively among basketball players harboring the CA genotype (p = 0.048).ConclusionsThe study’s findings indicate that the rs762551 CC genotype is a disadvantage in elite team sports, whereas the CA genotype provides an advantage in basketball performance.

The potential of indigenous Bacillus sp. BT3.1 as an antifungal biopesticide against the plant pathogen Fusarium oxysporum

Abstract. Nafidiastri FA, Lolita NT, Riqina HS, Aurora BZ, Geraldi A, Nurhariyati T, Supriyanto A, Ni’matuzahroh, Fatimah, Salamun. 2024. The potential of indigenous Bacillus sp. BT3.1 as an antifungal biopesticide against the plant pathogen Fusarium oxysporum. Biodiversitas 25: 2679-2686. Biosurfactants are green surfactants that bacteria can produce, one of which is Bacillus. This genus can produce lipopeptide-type biosurfactants, namely surfactin, that can inhibit the growth of fungal pathogens. This research aims to determine the biosurfactant activity on molasses substrates and the antifungal activity of isolate BT3.1 against Fusarium oxysporum. The biosurfactant activity test method tested hemolytic activity using the spot method, surface tension analysis, and emulsification activity. In addition, an antifungal activity test was also carried out using the swab method. Characterization of isolate BT3.1 was carried out macroscopically and microscopically. The macroscopic characteristics of isolate BT3.1 show that bacteria from the genus Bacillus are moderate in size, white, irregular with serrate colony edges, shiny raised elevations, and a shiny surface texture. Microscopic characteristics of the isolate showed Gram-positive bacteria with oval-shaped endospores in the center. Based on the results of the biosurfactant activity test, isolate BT3.1 showed beta-type hemolysis activity, reduced surface tension by 23.3 mN/m on distilled water and 12 mN/m on NB media, and produced an emulsion activity value of around 52%. The results of the production of crude extract of BT3.1 isolate on 2, 4, and 6% molasses substrates showed optimal biosurfactant activity at a concentration of 4% with an incubation time of 48 hours. The antifungal activity of isolate BT3.1 showed that 80% inhibited the growth of Fusarium oxysporum, so the indigenous bacteria Bacillus sp. BT-3.1 has the potential to be developed as a raw material candidate for antifungal biopesticides against the plant pathogen Fusarium oxysporum.

Comparison of methods for sampling and detection of carbapenemase-producing organisms in clinical handwash basin drains in health care

There are currently no standardised methods for the sampling and testing of clinical hand wash basin (HWB) samples for the detection of carbapenemase-producing organisms (CPO). Methods of sampling (drain aspirate versus swab from top of drain) and detection of CPO in clinical HWB drains in two different healthcare settings, one which was dealing with a hospital wide outbreak of CPO (hospital A) and another with no reported outbreaks (hospital B) were compared. Drain aspirates and swabs from HWB drains were tested using multiplex PCR together with culture-based methods. No significant difference in detection of CPO was found between drain aspirate or swab methods of sampling. Direct PCR on samples detected significantly more carbapenemase genes than culture on CARBA agar (p < 0.0001 and 0.0045 respectively). A higher percentage of HWB drains were positive in hospital A both by culture and direct PCR, and a significantly higher number of carbapenemase genes were detected in hospital A HWB drain aspirate both by PCR and culture (p = 0.014 and 0.0071 respectively). There was a high correlation between drain swab positivity by PCR and culture in hospital A (91%) compared to hospital B where it was only 33%. No difference could be found in drain contamination rates when HWB with rear drain was compared against those with drain directly below the tap. Colonisation of HWB at the top of the drain may be related to risk of cross transmission of CPO from healthcare environment to patients.

Comparative performance of contact plate metod and swab method for surface microbial contamination on medical fabrics

BackgroundThe contact plate method is widely accepted and used in various fields where hygiene and contamination levels are crucial. Evidence regarding the applicability of the contact plate method for sampling fabric microbial contamination levels in real medical environments was limited. This study aimed to assess the applicability of the contact plate method for detecting microbial contamination on medical fabrics in a real healthcare environment, thereby providing a benchmark for fabric microbial sampling methods.MethodsIn a level three obstetrics ward of a hospital, twenty-four privacy curtains adjacent to patient beds were selected for this study. The contact plate and swab method were used to collect microbial samples from the privacy curtains on the 1st, 7th, 14th, and 28th days after they were hung. The total colony count on each privacy curtain surface was calculated, and microbial identification was performed.ResultsAfter excluding the effects of time, room type, and curtain location on the detected microbial load, the linear mixed-effects model analysis showed that contact plate method yielded lower colony counts compared to swab method (P < 0.001). However, the contact plate method isolated more microbial species than swab method (P < 0.001). 291 pathogenic strains were isolated using the contact plate method and 133 pathogenic strains were isolated via the swab method. There was no difference between the two sampling methods in the detection of gram-negative bacteria (P = 0.089). Furthermore, the microbial load on curtains in double-occupancy rooms was lower than those in triple-occupancy rooms (P = 0.021), and the microbial load on curtains near windows was lower than that near doors (P = 0.004).ConclusionContact plate method is superior to swab method in strain isolation. Swab method is more suitable for evaluating the bacterial contamination of fabrics.

Preliminary study on the diversity and quantity analysis of oral bacteria according to the sampling methods

Objectives: Oral bacterial samples included subgingival, supragingival, and saliva plaques. As the diversity and number of microorganisms deffer depending on the area of the oral cavity and the method used, an appropriate and reliable collection method is important. The present study investigated oral bacterial sampling methods. Methods: Supragingival dental plaque was collected from the buccal and lingual tooth surfaces of study participants using sterilized cotton swabs. Plaques were collected from the subgingival area using a sterilized curette. Bacterial genomic DNA was extracted using MagNA Pure 96 DNA and Viral NA low-volume kits. Real-time polymerase chain reaction (PCR) was performed using the PowerCheck™ Periodontitis Pathogens Multiplex Real-time PCR kit. Results: Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Fusobacterium nucleatum of the orange complex were not observed in the subgingival biofilms of all study participants. For Porphyromonas. gingivalis, a significant correlation was observed between supragingival, subgingival, and total tooth surface biofilms. Compared to the supragingival and subgingival biofilmss, total tooth surface biofilm exhibited the highest bacterial count when the inswabbing method was used. Conclusions: Based on these findings, the supragingival swab method is recommended for oral bacterial research.

Evaluation of Oral Microflora-Related to Dental Caries and Salivary pH in type II Diabetic Patients.

Diabetes mellitus is one of the chronic diseases and a group of metabolic disorders characterized by a high blood sugar level over a prolonged period. The present study aimed to evaluate and correlate HbA1c, salivary pH, and oral bacterial microflora (streptococcus and lactobacillus colony-forming unit (CFU)) related to dental caries in normal, controlled, and uncontrolled type II diabetic patients. A total of 90 samples were taken for this study. The HbA1c test was recorded and grouped into three (normal, prediabetic, and diabetic). CFUs (streptococcus and lactobacillus) were evaluated by the spit-and-swab method. Salivary pH was measured with a pH strip with color coding. By using the post hoc test, the P-value was significant. The CFU of streptococcus and lactobacillus in the saliva spit and swab method is statistically significant for P <0.005 and P <0.01 among normal, prediabetic, and diabetic groups. In diabetic patients, there is a higher incidence of dental caries (s.d. 6.7), a higher CFU (s.d. 6194.5) in the bacterial microflora, and a lower salivary pH (s.d. 0.6) than in prediabetic and normal patients. From the present study, we conclude that there is a slight increase in the CFU of Streptococcus mutans in diabetic patients compared to non-diabetic patients. This CFU increase and decrease in salivary PH were strongly associated with increased dental caries in diabetic patients.

The use of Kudoh method for culture of Mycobacterium tuberculosis and Mycobacterium africanum in The Gambia.

Mycobacterium tuberculosis culturing remains the gold standard for laboratory diagnosis of tuberculosis. Tuberculosis remains a great public health problem in developing countries like The Gambia, as most of the methods currently used for bacterial isolation are either time-consuming or costly. To evaluate the Kudoh swab method in a West African setting in Gambia, with a particular focus on the method's performance when culturing Mycobacterium africanum West Africa 2 (MAF2) isolates. 75 sputum samples were collected in the Greater Banjul Area and decontaminated in parallel with both the standard N-acetyl-L-Cysteine-NaOH (NALC-NaOH) and the Kudoh swab method in the TB diagnostics laboratory in the Medical Research Council Unit The Gambia between 30th December 2017 and 25th February 2018. These samples were subsequently cultured on standard Löwenstein-Jensen and Modified Ogawa media respectively and incubated at 37°C for mycobacterial growth. Spoligotyping was done to determine if the decontamination and culture methods compared could equally detect Mycobacterium tuberculosis, Mycobacterium africanum West Africa 1 and Mycobacterium africanum West Africa 2. Among the 50 smear positives, 35 (70%) were culture-positive with Kudoh and 32 (64%) were culture positive with NALC-NaOH, whilst 7(28%) of the 25 smear negative samples were culture positive with both methods (Table 2). There was no significant difference in recovery between both methods (McNemar's test, p-value = 0.7003), suggesting that the overall positivity rate between the two methods is comparable. There were no differences in time-to-positivity or contamination rate between the methods. However, Kudoh yielded positive cultures that were negative on LJ and vice versa. All findings were irrespective of mycobacterial lineages. The Kudoh method has comparable sensitivity to the NALC-NaOH method for detecting Mycobacterium tuberculosis complex isolates. It is easy to perform and could be an add on option for mycobacterial culture in the field in The Gambia, since it requires less biosafety equipment.

Comparison of Three Preharvest Sampling Strategies to Monitor Pathogens in Cattle Lairage Areas

The objective of this study was to compare preharvest monitoring strategies by evaluating three different sampling methods in the lairage area to determine pathogen recovery for each sampling method and incoming pathogen prevalence from the cattle to inform in-plant decision making. Samples were gathered over a 5-month period, from February to June 2022, at a harvesting and processing facility located in Eastern Nebraska. Sampling methods included (i) fecal pats, (ii) boot swabs, and (iii) MicroTally swab. A total of 329 samples were collected over the study period (fecal pats: n = 105, boot swabs: n = 104, and MicroTally swabs: n = 120). Specific media combinations, an incubation temperature of 42°C, and incubation timepoints (18–24 h) were utilized for each matrix and the prevalence of Salmonella, Escherichia coli O157:H7, and six non-O157 Shiga-toxin producing E. coli (STEC) was evaluated using the BAX system Real-Time PCR assay. Overall, results from the study concluded that boot swabs were an effective sampling method for pathogen detection in the cattle lairage area. Boot swabs (97.1%) were statistically more likely to detect for Salmonella (p < 0.05) when compared to fecal pats (67.6%) and MicroTally swab (77.5%) methods. For E. coli O157:H7 and STEC – O26, O121, O45, and O103 prevalence, boot swabs were significantly better at detecting for these pathogens (p < 0.05) than MicroTally swabs (OR = 3.16 – 11.95) and a comparable sampling method to fecal pats (OR = 0.93 – 2.01, p > 0.05). Lastly, all three sampling methods detected a very low prevalence for E. coli O111 and O145; therefore, no further analysis was conducted. The boot swab sampling method was strongly favored because they require little training to implement, are inexpensive, and they do not require much sampling labor; therefore, would be a simple and effective sampling method to implement within the industry to evaluate pathogen prevalence preharvest.

The cotton swab method: an accurate and less invasive way to assess fecal consistency in weaned pigs

BackgroundResearchers and pig veterinarians are interested in assessing pigs’ fecal consistency. This study developed a standardized protocol and scale for the cotton swab method, which is a way of assessing the fecal consistency in pigs. The accuracy of the cotton swab method was evaluated in weaned pigs using fecal dry-matter analysis as a golden standard. The study also proposed fecal dry-matter percentage thresholds for the categorization of fecal consistency on a four-point scale.ResultsThe thresholds of 10.3%, 16.6%, and 21.9% fecal dry-matter were suggested for categorization of the consistency of fecal samples on a four-point scale. The accuracy of the cotton swab method was high. The agreement to the four-point fecal consistency score derived from the fecal dry-matter percentage was almost perfect (weighted Gwet’s agreement coefficient = 0.87 [95% confidence interval: 0.84; 0.91]). The cotton swab method had a sensitivity of 85.0% (95% confidence interval: 76.5; 91.4) and a specificity of 95.2% (95% confidence interval: 92.0; 97.3) when used to diagnose whether pigs had diarrhea or not. For non-diarrheic pigs, the method almost always (n = 287/289) required less handling than the collection of a fecal sample by digital rectal manipulation.ConclusionThe cotton swab method is an accurate way to assess fecal consistency in pigs, both on a four-point scale and as a dichotomous diarrhea score. The method is quick to perform and less invasive than methods relying on the collection of fecal samples. New fecal dry-matter thresholds between feces of different consistencies were proposed.

A flexible semiconductor SERS substrate by in situ growth of tightly aligned TiO2 for in situ detection of antibiotic residues.

Semiconductor materials have become a competitive candidate for surface-enhanced Raman scattering (SERS) substrate. However, powdered semiconductors are difficult to execute a fast in situ detection for trace analytes. Here, we developed a new flexible semiconductor SERS substrate by in situ densely growing anatase TiO2 nanoparticles on the surface of cotton fabric through a filtration-hydrothermal method, in which TiO2 exhibits excellent controllability in size and distribution by regulating the ratio of water to alcohol in synthesis and the number of filtration-hydrothermal repetitive cycle. Cotton fabric/TiO2 (Cot/TiO2) substrate exhibits a high SERS activity and excellent spectral repeatability. The developed substrate has an ultra-high stability that can withstand long-term preservation; it can even resist the corrosions of strong acid and alkali, as well as high temperature up to 100°C and low temperature down to - 20°C. The flexible substrate can be used to carry out a rapid in situ detection for quinolone antibiotic (enrofloxacin and enoxacin) residues on the fish body surface by using a simple swabbing method, with highquantitative detection potential (up to an order of magnitude of 10-7M), and even for the simultaneous detection of both drug residues. The flexible substrate also exhibits an excellent recyclability up to 6 recycles in the actual SERS detection.

Comparison of swabbing and cutting-out DNA collection methods from cotton, paper, and cardboard surfaces

Choosing an inappropriate method of sample collection can often have a detrimental impact on DNA recovery. Multiple studies highlight the importance of selecting the recovery method based on the type of surface the DNA sample is located on. This study aimed to investigate the efficacy of sample collection via the single cotton swabbing method in comparison to recovery directly from the material cut from the surface. The three types of surfaces included cotton, paper, and cardboard. DNA sources comprised cell-free and cellular DNA, as well as blood and saliva as examples of body fluids commonly encountered at crime scenes. The data analysis revealed that the cutting-out method resulted in higher DNA recovery from all but cardboard surfaces, making it the more efficient collection method. Despite its limitations, the cutting-out method should be considered as the DNA recovery method of choice when suitable.

Novel approach for detecting classical swine fever virus from swabs of wild boar cut tails using nested real-time PCR.

We devised a method to detect the classical swine fever virus (CSFV) in tail-wiped swabs from wild boars. The CSFV gene in swabs was detected with high sensitivity using nested real-time polymerase chain reaction (PCR), which is a combination of reverse transcription-PCR (RT-PCR) and real-time PCR. We compared CSFV gene detection from boar tissue using the conventional and our tail-wiped swab method. The tail-wiped swab method showed sensitivity and specificity of 100% (26/26) and 98.8% (172/174), respectively compared to the conventional method. Thus, the swab-based CSFV detection method was considered to have detection sensitivity comparable to that of conventional methods. Additionally, we conducted surveillance for CSFV in wild boars on Awaji Island. CSFV was detected in 10.7% (45/420) of samples.

Efficacy of SARS-CoV-2 detection from used surgical masks compared with standard detection method

The real-time reverse transcription-polymerase chain reaction (RT-PCR) test is the gold standard for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection. Proper specimen collection and obtaining a sufficient specimen are the most essential steps for laboratory diagnosis. The nasopharyngeal (NP) swab is recommended as the reference collection method. However, NP swab collection is invasive and uncomfortable for patients and poses some risk to healthcare workers. This study aimed to compare the efficacy of SARS-CoV-2 RNA detection from surgical masks with the NP swab method using RT-PCR testing. Of 269 patients, RT-PCR RNA from NP swabs was detected among 82 patients (30.5%) and was undetected among 187 patients (69.5%). All patients were tested for SARS-CoV-2 RNA from surgical masks. SARS-CoV-2 RNA was detected in 25/82 (30.5%) surgical mask filters, while undetected among 57 (69.5%). For the surgical mask with an average use time of 7.05 h, the sensitivity was 30.5%, the specificity was 100.0%, with positive predictive value of 100.0% and negative predictive value of 76.2%. Therefore, surgical masks could be an alternative non-invasive specimen source for SARS-CoV-2 RT-PCR testing. The results of our study suggest that the test could be employed after wearing surgical masks for at least 8-12 h, with increased sensitivity when used for more than 12 h.