An experimental verification of fungal overgrowth in temporary houses at the site of the Great East Japan Earthquake.

Fungal contamination in the indoor air of prefabricated temporary houses at the site of the Great East Japan Earthquake revealed extremely high levels compared to those found in conventional residences. We experimentally investigated fungal growth levels on different interior materials to support fungal overgrowth in prefabricated temporary houses. Three species each of allergenic fungi and invasive fungi observed in temporary housing were selected for inoculation tests with various interior materials. The experiments with fungal inoculation were conducted in conformance with standards for industrial products described in the Japanese" JIS Z 2911:2018 Methods of test for fungus resistance" with small modifications. After incubation, visual and stereomicroscopic assessments were performed to determine fungal growth levels. The viability of the fungi varied according to the interior material type. Our findings demonstrate the importance of antifungal measures in indoor environments and the need for additional research on the growth levels of fungal species on various interior materials.

Real-World Effectiveness of High-Dose Olanzapine and Clozapine for Treatment-Resistant Schizophrenia in Japan: A Retrospective Bidirectional Mirror-Image Study.

BACKGROUND: Clozapine is considered the gold standard medication for treatment-resistant schizophrenia (TRS). However, given that clozapine treatment is associated with the burden of regular blood monitoring and the risk of life-threatening adverse effects, high-dose olanzapine can serve as an alternative treatment. We conducted a bidirectional mirror-image study to evaluate the effectiveness of high-dose olanzapine compared with clozapine. METHODS: We included patients with TRS who switched from olanzapine to clozapine or switched from clozapine to olanzapine, and received high-dose (>20 mg/d) olanzapine treatment for ≥4 weeks at Yamanashi Prefectural Kita Hospital. We obtained data on hospitalization, seclusion, and modified electroconvulsive therapy (mECT) during the clozapine phase and the olanzapine phase. RESULTS: A total of 44 patients were included. When patients switched from high-dose olanzapine to clozapine (n = 32), significant reductions were found in the total days of seclusion, the total number of mECT, and the number of patients who received mECT at least once. When patients switched from clozapine to high-dose olanzapine (n = 12), a significant reduction was found in the number of patients who received mECT at least once. When data from both directions of treatment were combined, significant reductions were found in the total days of seclusion, the total number of mECT, and the number of patients who received mECT at least once in favor of clozapine. CONCLUSIONS: Findings suggest that high-dose olanzapine may not be as effective as clozapine for patients with TRS in real-world practice. However, it should be noted that there are unique circumstances that restrict the use of clozapine in Japan.

Patterns of long-term care service use and multimorbidity in older Japanese adults: A cross-sectional study of claim data.

AIM: The long-term care (LTC) insurance system provides a combination of several services in Japan; therefore, it is important to clarify service utilization. Furthermore, it is important to consider multimorbidity among older adults, who frequently present several diseases. This study aimed to clarify LTC service utilization patterns, including those for newly added multifunctional services, and to describe the basic characteristics, including multimorbidity, of these patterns. METHODS: We included 37 419 older adults in care need levels 1-5, living at home, who used LTC services in October 2017. We used LTC and medical claims data that were linked using unique identifiers from the National Health Insurance, Advanced Elderly Medical Insurance, and LTC Insurance of Shizuoka Prefecture in Japan. LTC service utilization patterns were identified using cluster analysis based on service fees. Multimorbidity was analyzed using the Charlson Comorbidity Index (CCI) and compared characteristics in these patterns. RESULTS: Six LTC service utilization patterns were identified: light use (51.0%), intensive use of day care (33.7%), intensive use of short stay (6.3%), intensive use of home help (5.1%), multifunctional LTC in small-group homes (MLS) use (3.7%), and MLS and home-visiting nurses (MLSH) use (0.2%). MLSH use had the highest CCI (3.6 ± 2.3). Intensive use of day care and short stay had the lowest CCI (2.6 ± 1.9). CONCLUSIONS: The characteristics of multimorbidity differed by LTC service utilization patterns. Our findings are useful for considering service utilization that takes into account the characteristics of older adults. Geriatr Gerontol Int 2024; 24: 283-289.

Physical function decline predictors in nursing home residents using new national quality indicators.

AIM: To determine the predictors of physical function (PF) decline among nursing home residents using items from the Long-term care Information system For Evidence (LIFE), a system launched in 2021 to ensure the quality of long-term care. METHODS: The LIFE data of 1648 residents from 45 nursing homes in Japan were retrospectively collected in July 2021 (T0) and January 2022 (T1), including demographics, PF assessed by the Barthel index (BI), nutrition and oral health, and cognitive function. The Dementia Behavior Disturbance scale was used to assess the frequency of certain behaviors, such as "waking at midnight." The predictors of PF decline, defined as a decrease ≥5 in the BI score at T1 compared with that at T0, were determined using mixed-effects logistic regression analyses. PF at T0 was classified into high (>60 BI) and low (≤60 BI) groups. RESULTS: The participants' mean age was 87.2 ± 7.1 years, and 45.3% experienced PF decline. The significant predictors of PF decline were age ≥ 90 years, body mass index <18.5 kg/m2 , dementia diagnosis, moderate and severe cognitive impairments, not vocalizing reciprocal exchanges at will, always "waking at midnight," and high PF at T0. CONCLUSIONS: The LIFE items predicted PF decline among nursing home residents, suggesting that LIFE data can be used to ensure the quality of long-term care. Geriatr Gerontol Int 2024; 24: 123-132.

The Process of Home-Visiting Nurses Supporting People with Mental Disorders.

The number of people with mental disorders (PMD) living in the community is increasing; however, it is unclear how home-visiting nurses (HVNs) supporting them in the community acquire their support skills. This study aimed to reveal the process of how HVNs learn support skills for PMD. Semi-structured interviews were conducted with 14 HVNs supporting PMD living in the community. The grounded theory approach was used for data analysis. As a result, two stages were present: "Explore the personal recovery of PMD" and "Believe in the potential of PMD and accompanying them". The first stage is further divided into two themes: "Overlapping the worlds of PMD and HVNs", and "Easing difficulty in living for PMD". In the first stage, HVNs gained a better understanding of PMD and obtained insight into the support they needed in their daily lives. In the second stage, HVNs became to provide the support that PMD truly needed. HVNs gained a deeper understanding of the reality of PMD through their support. After HVNs found the support PMD required, they sought to provide it, ultimately resulting in finding ways to facilitate the personal recovery of PMD.

Unplanned Hospital Visits and Poor Oral Health With Undernutrition in Nursing Home Residents.

OBJECTIVES: In 2021, the Japanese government began operating a long-term care (LTC) database called the Long-Term Care Information System for Evidence (LIFE). However, its utility has not been verified. Regarding unplanned hospital visits of nursing home residents, one of the challenges in LTC is that poor oral health with undernutrition could indicate high-risk residents. Therefore, this study examined the association between poor oral health with undernutrition assessed using the LIFE data and unplanned hospital visits of nursing home residents. DESIGN: Retrospective cohort study. SETTING AND PARTICIPANTS: The participants were 237 residents aged ≥65 years in 4 nursing homes in Japan. The analyses included 1041 LIFE data entries repeatedly measured for the participants every month and unplanned hospital visit data during the observation period. METHODS: The participants' LIFE and unplanned hospital visit data were obtained from the nursing home providers. Poor oral health was defined using oral items included in the LIFE data and body mass index. Using the LIFE data, the association between poor oral health and unplanned hospital visits within 1 month after LIFE assessment entries was analyzed. The odds ratios (ORs) and 95% CIs were calculated using a generalized linear mixed model. RESULTS: In total, 59 of 1041 LIFE data (5.7%) entries were unplanned hospital visits within 1 month after LIFE assessment. Among patient characteristics, significant differences were noted in dementia diagnosis [OR (95% CI): 2.66 (1.26-5.63)], although no significant differences were observed in other characteristics. Multivariate analysis using participant identification as a random effect confirmed that poor oral health was associated with unplanned hospital visits within 1 month [adjusted OR (95% CI): 2.63 (1.05-6.61)]. CONCLUSIONS AND IMPLICATIONS: Poor oral health assessed using the LIFE data could be used as an indicator to identify nursing home residents at high risk for unplanned hospital visits.

Toward developing care outcome quality indicators for home care for older people: A prospective cohort study in Japan.

INTRODUCTION: Care quality in Japan's long-term care (LTC) agencies, including home care, is the responsibility primarily of individual agencies, and the evaluation of service processes and outcomes is minimal. OBJECTIVES: To describe the development of quality indicators for LTC (QIs-LTC) in Japan. METHODS: QIs-LTC were developed through literature review and expert panel discussions and then were piloted and used in a 2-year longitudinal survey. The survey (launched in September 2019) targeted older people receiving home care (n = 1450), their family members (n = 880), their professional home care providers (n = 577), and managers of home care agencies (n = 122). RESULTS: Across eight domains (maintaining dignity, minimizing symptoms and disease deterioration, maintaining nutritional status, maintaining bladder/bowel control, encouraging physical activities, experiencing sound sleep, maintaining serenity and contentedness, and maintaining family's well-being), 24 care quality objectives were set with 24 outcome QIs-LTC and 144 process QIs-LTC. In the survey, 84.8% of clients were using home care nursing, 26.3% were living alone, and 39.5% had dementia. In the month preceding the data collection, 13.9% of clients had a new disease or worsening of an existing disease, 8.8% were hospitalized at least once, and 47.9% did not participate in activities of interest. About 20% of clients' families were unable to spend time peacefully, and 52.8% were exhausted from the client's care. CONCLUSIONS: The QIs-LTC developed in the current study are generic and client- and family-centered. They encompass objective and subjective information and would facilitate standardized monitoring if adopted and comparison between LTC settings, including home care. In addition, future research directives are outlined. Geriatr Gerontol Int 2023; 23: 383-394.

Determination of the biological origin of enzyme preparations using SDS-PAGE and peptide mass fingerprinting.

Enzymes are mainly extracted from the culture broth of microorganisms. Various commercially available enzyme preparations (EPs) are derived from different microorganisms, and the source of the EP should be the same as that mentioned in the manufacture's information. The development of analytical methods that can determine the origin of the final products is important for ensuring that the EPs are nontoxic, especially when used as food additives. In this study, various EPs were subjected to SDS-PAGE, and the main protein bands were excised. After in-gel digestion, the generated peptides were analysed using MALDI-TOF MS, and protein identification was performed by searching the set of peptide masses against protein databases. In total, 36 EPs including amylase, ß-galactosidase, cellulase, hemicellulase and protease were analysed, and the information about the enzyme sources was obtained for 30 EPs. Among these, the biological sources determined for 25 EPs were consistent with the manufacturer's information; for the remaining five, enzymes produced by closely-related species were shown as matching proteins due to high sequence similarity. Six enzymes derived from four microorganisms could not be identified because their protein sequences were not registered in the database. As these databases are expanded, this approach of using SDS-PAGE and peptide mass fingerprinting (PMF) can determine the biological origin of enzymes rapidly and contribute to ensuring the safety of EPs.

[Suitability of Culture Broth and Conditions for Escherichia coli Growth and Gas Production as a Test for Food Additives in EC Broth].

The growth and gas production test for Escherichia coli in the microbiological examination of food additives is stipulated in the ninth edition of Japan's Specifications and Standards for Food Additives (JSFA) and described as a part of the "Confirmation Test for Escherichia coli" in "Microbial Limit Tests" in the same manuscript. The growth and gas production test for E. coli indicated that the positive or negative of "gas production and/or turbidity" in EC broth should be confirmed after incubating at 45.5±0.2℃ for 24±2 h. If both gas production and turbidity are negative, the culture is additionally incubated up to 48±2 h to determine E. coli contamination. The internationally referenced Bacteriological Analytical Manual of the U.S. FDA had revised the incubation temperature in tests for coliforms and E. coli from 45.5±0.2℃ to 44.5±0.2℃ in 2017. Therefore, we conducted research in anticipation of this temperature change being reflected in the microbiological examination of the JSFA. We used seven EC broth products and six food additives across eight products that are available in Japan in order to compare the growth and gas production at temperatures of 45.5±0.2℃ and 44.5±0.2℃ of E. coli NBRC 3972, which is designated as the test strain in JSFA. Both with/without food additives, the number of EC broth products in which medium turbidity and gas production by the strain were positive in three out of three tubes at all test times was greater at 44.5±0.2℃ than at 45.5±0.2℃. These results suggest that the growth and gas production test for E. coli could be more appropriately conducted by incubation at 44.5±0.2℃ in the "Confirmation Test for Escherichia coli" for E. coli in the JSFA in comparison to 45.5±0.2℃. Furthermore, there were differences in the growth and gas production of E. coli NBRC 3972 depending on the EC broth product used. Therefore, the importance of "Media growth promotion test" and "Method suitability test" in the ninth edition of the JSFA should be emphasized.

The Mechanism of Ochratoxin Contamination of Artificially Inoculated Licorice Roots.

Ochratoxin (OT) contamination of medicinal herbs is a serious threat to human health. This study was performed to investigate the mechanism of OT contamination of licorice (Glycyrrhiza sp.) root. Licorice root samples were cut into eight parts, which were placed separately on sucrose-free Czapek Dox agar medium, inoculated with the spores of ochratoxigenic Aspergillus westerdijkiae. After incubation for 10 and 20 days, the OT contents of the samples were determined by high-performance liquid chromatography, and microtome sections prepared from the samples were analyzed by desorption electrospray ionization tandem mass spectrometry, to visualize OT localization. The same sections were further examined by light microscopy and scanning electron microscopy, to investigate the path of fungal mycelial penetration of the inner roots. OT concentrations tended to increase from the upper- to the middle-root parts. OTs were located in cut areas and areas of cork layer damage; they were not present in the undamaged cork layer, indicating that the structure of this layer prevents OT contamination of the licorice root.

Antimicrobial resistance profiles of Campylobacter jejuni and Salmonella spp. isolated from enteritis patients in Japan.

Understanding the antimicrobial resistance of Campylobacter jejuni and Salmonella spp. isolated from patients with enteritis will aid in therapeutic decision-making. This study aimed to characterize C. jejuni and Salmonella spp. isolates from patients with enteritis. For C. jejuni, the resistance rates against ampicillin, tetracycline, and ciprofloxacin were 17.2%, 23.8%, and 46.4%, respectively. All the C. jejuni isolates were susceptible to erythromycin, which is recommended as a first-choice antimicrobial if Campylobacter enteritis is strongly suspected. C. jejuni was classified into 64 sequence types (STs), and the five major STs were ST22, ST354, ST21, ST918, and ST50. The ciprofloxacin-resistance rate of ST22 was 85.7%. For Salmonella, the resistance rates against ampicillin, cefotaxime, streptomycin, kanamycin, tetracycline, and nalidixic acid were 14.7%, 2.0%, 57.8%, 10.8%, 16.7%, and 11.8%, respectively. All the Salmonella spp. isolates were susceptible to ciprofloxacin. Therefore, fluoroquinolones are the recommended antimicrobials against Salmonella enteritis. S. Thompson, S. Enteritidis, and S. Schwarzengrund were the three most prevalent serotypes. The two cefotaxime-resistant isolates were serotyped as S. Typhimurium and were found to harbor blaCMY-2. The results of this study would help select antimicrobials for treating patients with Campylobacter and Salmonella enteritis.

Analysis of risk factors for post-tonsillectomy hemorrhage in adults.

OBJECTIVES: To identify the risk factors for post-tonsillectomy hemorrhage (PTH) in adult patients (>19 years). METHODS: 275 adult patients who underwent tonsillectomy between 2009 and 2019 were retrospectively analyzed. Possible risk factors associated with PTH were investigated by univariate and multivariate logistic regression analyses. RESULTS: PTH occurred in 39 of 275 patients (14.2%). Regarding underlying diseases, PTH occurred more frequently in focal infection of IgA nephropathy. Furthermore, bipolar electrocautery was the other risk factor for PTH on multivariate analysis. CONCLUSION: Focal infection of IgA nephropathy and bipolar electrocautery were identified as the risk factors for PTH.

Distribution of periodontopathic bacterial species between saliva and tonsils.

Periodontopathic bacteria cause an inflammatory disease localized in the periodontal tissue and are associated with various conditions in other body parts. The distribution of periodontopathic bacterial species in the tonsils is unknown, even though the tonsils are located close to the oral cavity, and inflammation of the tonsils causes various systemic diseases. We detected the major periodontopathic bacterial species residing in saliva and tonsil specimens from 25 subjects undergoing tonsillectomy. Nine of the ten major periodontopathic bacterial species were detected by polymerase chain reaction of tonsil specimens, among which Campylobacter rectus was the most common (80.0%), followed by Porphyromonas gingivalis (36.0%). The other seven types of periodontopathic bacterial species were distributed with 0% to 25.0% abundance in the tonsil specimens. C. rectus had a high detection rate in tonsil specimens (> 75.0%), regardless of whether it was detected in the corresponding saliva specimens. However, the detection rate for P. gingivalis in tonsil specimens was significantly higher in subjects with P. gingivalis-positive saliva (77.8%) than in those with P. gingivalis-negative saliva (6.3%; P < 0.001). Furthermore, 75.0% of P. gingivalis in tonsil specimens did not have the known fimA gene that encodes the 41-kDa filamentous appendage protein FimA, which is expressed on the cell surface of the bacteria. Our results suggest that certain periodontopathic bacterial species are detected in the tonsils either independently of or depending on their distribution in the oral cavity and may be involved in tonsil-related diseases.

Preparation of Monoclonal Antibodies Specifically Reacting with the Trichothecene Mycotoxins Nivalenol and 15-Acetylnivalenol via the Introduction of a Linker Molecule into Its C-15 Position.

Nivalenol (NIV) is a trichothecene mycotoxin that is more toxic than deoxynivalenol. It accumulates in grains due to infection with Fusarium species, which are the causative agents of scab or Fusarium head blight. An immunoassay, which is a rapid and easy analytical method, is necessary for monitoring NIV in grains. However, a specific antibody against NIV has not been prepared previously. To establish an immunoassay, we prepared NIV, introduced a linker, and generated antibodies against it. NIV was prepared from a culture of Fusarium kyushuense obtained from pressed barley through chromatographic procedures with synthetic adsorbents and silica gel. NIV was reacted with glutaric anhydride, and the reaction was stopped before mono-hemiglutaryl-NIV was changed to di-hemiglutaryl-NIV. 15-O-Hemiglutaryl-NIV was isolated via preparative HPLC and bound to keyhole limpet hemocyanin (KLH) using the active ester method. Two different monoclonal antibodies were prepared by immunizing mice with the NIV-KLH conjugate. The 50% inhibitory concentration values were 36 and 37 ng/mL. These antibodies also showed high reactivity in a direct competitive enzyme-linked immunosorbent assay and specifically reacted with NIV and 15-acetyl-NIV but not with deoxynivalenol and 4-acetyl-NIV.

Dietary Patterns of 479 Indonesian Adults and Their Associations with Sodium and Potassium Intakes Estimated by Two 24-h Urine Collections.

The excess sodium (Na) intake and insufficient potassium (K) intake are frequently observed all over the world, including Indonesia. This study explored the dietary patterns of Indonesian people and evaluated their associations with Na and K intakes. Na and K intakes were assessed by repeated 24-h urine collection. The dietary patterns of the previous month were extracted by factor analysis using the Indonesian Food Frequency Questionnaire. The participants were community-dwelling Indonesian men and women (n = 479) aged 20 years and over. We identified four dietary patterns in each sex. After controlling for confounding factors, the high quantile of 'Noodle, oil, and salty sea products' pattern was associated with the high Na intake in both men and women (p = 0.02 and <0.001, respectively). The 'Meat, vegetable, oil, and fruit' pattern statistically significantly contributed to the high K intake in men (p = 0.04), but not in women (p = 0.26). The 'Vegetable, non-oil, and milk' pattern in men and 'Meat, vegetable, and fruit' pattern in women were associated with low Na:K ratios (p = 0.03 and 0.01, respectively). Neither 'bread' nor 'fish' appeared as a major determinant of any dietary patterns in this population. The 'Noodle, oil, and salty sea products' pattern should be avoided to reduce sodium intake.

Family-oriented interventions in long-term care residential facilities for older people: A scoping review of the characteristics and outcomes.

INTRODUCTION: Family-oriented interventions in long-term care (LTC) residential facilities are heterogenous in design, characteristics, and outcomes. OBJECTIVES: To synthesize characteristics (e.g., type, provider, and duration) and outcomes of family-oriented interventions in LTC residential facilities. METHODS: We followed the JBI methodology and searched seven databases for quantitative, qualitative, and mixed method studies that reported family-oriented interventions in LTC residential settings for older people; defined in this review as ≥60 years. Interventions that included residents, resident families, health professionals, or any combinations of these three were included if the study reported post-intervention assessment of at least one family-related outcome. RESULTS: Thirteen studies met the inclusion criteria. Interventions were found to be multifaceted, and education was the most common element. Nurses were the most common intervenors, and most interventions had more than one target (residents, resident families, or staff). Most outcomes were related to family involvement, satisfaction with care, quality of life, communication, symptom management, and shared decision making, and none of the studies reported a negative impact. CONCLUSIONS: Family-oriented interventions were associated with high care quality and better resident-staff-family partnership. Staff education and staff-family conversation are relatively cheap interventions to help family involvement, facilitate shared decision-making, and improve family satisfaction.

Survival of SARS-CoV-2 and bovine coronavirus on common surfaces of living environments.

Aerosols or saliva containing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can contaminate living environments, and viruses can be indirectly transmitted. To understand the survival potential of the virus, the viral titers of bovine coronavirus (BCoV), as a model virus, and SARS-CoV-2 were measured on porous and non-porous surfaces. The amount of infectious BCoV recovered remained relatively high on non-porous substrates. However, it quickly decreased on several non-porous surfaces such as nitrile rubber. The time taken to reach the limit of detection on non-woven masks, as a porous substrate, was longer than that of non-porous substrates. On porous substrates other than non-woven masks, the amount of virus recovered quickly decreased, and then remained at a low level. Representative substrates were tested with SARS-CoV-2. The decrease in the amount of infectious virus recovered was similar to that of BCoV, although that of SARS-CoV-2 was more rapid. RNA derived from SARS-CoV-2 was also detected using real-time PCR, and it remained on surfaces much longer than infectious virus, on all substrates. Therefore, it is important to measure the viral titer to avoid the overestimation of infectious virus contamination in the environments. Our results suggest that the surface structure was not directly related to viral survivability.

Cross-genus inhibitory activity of polyoxins against aflatoxin production by Aspergillus parasiticus and fumonisin production by Fusarium fujikuroi.

Co-exposure to aflatoxin and fumonisin is a health concern where corn is a staple food, and a method to prevent co-contamination of these mycotoxins in foods is urgently needed. Polyoxins are chitin synthase inhibitors produced by Streptomyces cacaoi var. asoensis. The aflatoxin production inhibitory activity of a commercially available polyoxin D and four polyoxins purified from polyoxin AL water-soluble powder, an agricultural chemical containing polyoxins, was tested. The five polyoxins dose-dependently inhibited aflatoxin production by Aspergillus parasiticus and the IC50 values of polyoxin A, B, D, K and L were 16, 74, 110, 9 and 280 µmol L-1, respectively. Polyoxins also inhibited fumonisin production by Fusarium fujikuroi, and the IC50 values of polyoxin B, D, K and L were 270, 42, 65 and 62 µmol L-1, respectively. Polyoxins repressed the transcription of genes encoding proteins required for aflatoxin biosynthesis in A. parasiticus and fumonisin biosynthesis in F. fujikuroi. Polyoxin K and D also inhibited conidiation in A. parasiticus and F. fujikuroi, respectively. These results suggest that a mixture of polyoxins may effectively prevent co-contamination of aflatoxin and fumonisin in foods.

Matrix-Assisted Laser Desorption and Ionization Time-of-Flight Mass Spectrometry Analysis for the Direct Detection of SARS-CoV-2 in Nasopharyngeal Swabs.

The most common diagnostic method used for coronavirus disease-2019 (COVID-19) is real-time reverse transcription polymerase chain reaction (PCR). However, it requires complex and labor-intensive procedures and involves excessive positive results derived from viral debris. We developed a method for the direct detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal swabs, which uses matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-ToF MS) to identify specific peptides from the SARS-CoV-2 nucleocapsid phosphoprotein (NP). SARS-CoV-2 viral particles were separated from biological molecules in nasopharyngeal swabs by an ultrafiltration cartridge. Further purification was performed by an anion exchange resin, and purified NP was digested into peptides using trypsin. The peptides from SARS-CoV-2 that were inoculated into nasopharyngeal swabs were detected by MALDI-ToF MS, and the limit of detection was 106.7 viral copies. This value equates to 107.9 viral copies per swab and is approximately equivalent to the viral load of contagious patients. Seven NP-derived peptides were selected as the target molecules for the detection of SARS-CoV-2 in clinical specimens. The method detected between two and seven NP-derived peptides in 19 nasopharyngeal swab specimens from contagious COVID-19 patients. These peptides were not detected in four specimens in which SARS-CoV-2 RNA was not detected by PCR. Mutated NP-derived peptides were found in some specimens, and their patterns of amino acid replacement were estimated by accurate mass. Our results provide evidence that the developed MALDI-ToF MS-based method in a combination of straightforward purification steps and a rapid detection step directly detect SARS-CoV-2-specific peptides in nasopharyngeal swabs and can be a reliable high-throughput diagnostic method for COVID-19.