Parechovirus A3 (PeVA3) was first reported in 2004 and has been recognized as a causative agent of mild and severe infectious diseases in children. We first reported an outbreak of PeVA3-associated myalgia (PeVA3-M) in Yamagata, Japan, in 2008. We have repeatedly observed PeVA3-M cases in 2011, 2014, and 2016, and identified the first child case in 2014. Reports of PeVA3-M have increased since 2014, indicating that the recognition of PeVA3-M has spread across Japan. The findings showed that PeVA3-M commonly occurs among adults aged 30–40 years, particularly in males. Elevation of creatinine phosphokinase, C-reactive protein, and myoglobin, as well as magnetic resonance imaging findings, suggest inflammation of the muscles and/or fascia of the four limbs. Patients recover within 1–2 weeks without any sequelae. A longitudinal molecular epidemiological study in Yamagata revealed that PeVA3 strains cause a variety of diseases, ranging from mild to severe, including PeVA3-M, in subjects ranging from neonates to adults, irrespective of their genetic cluster. As PeVA3-M has not yet been reported abroad, more widespread recognition of PeVA3-M as an emerging disease is important. We hope this review will help clinicians and researchers in understanding PeVA3-M and therefore advance related research in Japan as well as around the world.

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Little is known about the therapeutic use of hydroxychloroquine in pediatric patients with coronavirus disease 2019 (COVID-19). Here, we retrospectively retrieved data of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PCR-positive pediatric patients from 20 hospitals in 8 Turkish cities. We obtained epidemiological, clinical, and laboratory features of the patients, as well as the drugs used for treating COVID-19. A total of 237 nasopharyngeal swab SARS-CoV-2 PCR-positive children were included in the study from March 26, 2020 to June 20, 2020. The mean age of asymptomatic children (118 ± 62 months) was higher than that of symptomatic children (89 ± 69 months). Symptomatic children had significantly lower mean lymphocyte counts and higher mean CRP, D-dimer, procalcitonin, and LDH levels than asymptomatic children in the univariate analysis. Among 156 children, 78 (50%), 15, 44, and 21 were treated with a hydroxychloroquine-containing regimen, hydroxychloroquine + azithromycin + oseltamivir, hydroxychloroquine + azithromycin, and hydroxychloroquine alone, respectively. Among 156 patients who received medical treatment, 90 (58%) underwent pre- and/or post-treatment electrocardiogram (ECG). However, none of them had ECG abnormalities or required hydroxychloroquine discontinuation due to adverse drug reactions.

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Human papillomavirus (HPV) infection is one of the most commonly reported sexually transmitted infections. Persistent infection is associated with the development of cervical cancer. Men may serve as a medium for HPV transmission among women, and much remains unknown about the prevalence and genotypes of HPV infection among men in Yunnan Province. This study was designed to investigate these parameters among men in this region. Clinical information was collected from January 2015 to May 2020, and 369 men who wished to undergo tests for HPV were included in this study. HPV screening was performed using the HPV GenoArray Test Kit, and the anatomical site of sample collection was the urethra. The mean age was 36.15 ± 9.08 years. Our results revealed that the prevalence of HPV infection among men was 23.85% in Yunnan Province, and there was no association between age and HPV prevalence in men. There were 72 (81.81%) individuals positive for a single HPV type, and 16 (18.19%) positive for multiple HPV types. The most prevalent oncogenic HPV types were found to be 52, 51, and 16. The most prevalent types of HPV infection were similar between men and women in this region, though the prevalence of HPV in men was relatively high.

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Isolation of seasonal coronaviruses, which include human coronavirus (HCoV) OC43, HCoV-HKU1, and HCoV-NL63, from primary cultures is difficult because it requires experienced handling, an exception being HCoV-229E, which can be isolated using cell lines such as RD-18S and HeLa-ACE2-TMPRSS2. We aimed to isolate seasonal CoVs in Yamagata, Japan to obtain infective virions useful for further research and to accelerate fundamental studies on HCoVs and SARS-CoV-2. Using modified air-liquid interface (ALI) culture of the normal human airway epithelium from earlier studies, we isolated 29 HCoVs (80.6%: 16, 6, 6, and 1 isolates of HCoV-OC43, HCoV-HKU1, HCoV-NL63, and HCoV-229E, respectively) from 36 cryopreserved nasopharyngeal specimens. In ALI cultures of HCoV-OC43 and HCoV-NL63, the harvested medium contained more than 1 × 10⁴ genome copies/µL at every tested time point during the more than 100 days of culture. Four isolates of HCoV-NL63 were further subcultured and successfully propagated in an LLC-MK2 cell line. Our results suggest that ALI culture is useful for isolating seasonal CoVs and sustainably obtaining HCoV-OC43 and HCoV-NL63 virions. Furthermore, the LLC-MK2 cell line in combination with ALI cultures can be used for the large-scale culturing of HCoV-NL63. Further investigations are necessary to develop methods for culturing difficult-to-culture seasonal CoVs in cell lines.

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The prognostic value of interleukin-6 (IL-6) in coronavirus disease 2019 (COVID-19) needs to be clarified. In this retrospective study, COVID-19 patients treated at Renmin Hospital of Wuhan University from January 7 to February 8, 2020 with measurements of serum IL-6 levels within 1 week after admission were included. Data regarding demographics, clinical characteristics, laboratory tests, complications, and outcomes were collected and analyzed. Sixty-six patients diagnosed with COVID-19 were included in this study (31 patients were females). They were divided into a normal group (serum IL-6 <10 pg/mL, n = 35) and an abnormal group (serum IL-6 <10 pg/mL, n = 31). Compared with the normal group, the incidence of critical cases (P <0.001), acute respiratory distress syndrome (ARDS) (P = 0.001), acute cardiac injury (P = 0.002), cardiac insufficiency (P = 0.039), mechanical ventilation rate (P = 0.002), and mortality (P = 0.021) was significantly increased in the abnormal group. Serum IL-6 concentration was an independent predictor of fatal outcome (P = 0.04). The optimal cutoff value of serum IL-6 concentration for predicting fatal outcomes was 26.09 pg/mL (P <0.001). In COVID-19, elevated serum IL-6 levels were associated with critical illness, use of mechanical ventilation, and complications, including heart injury and ARDS, and could predict a fatal outcome. Early detection of serum IL-6 levels after admission should be necessary in COVID-19 patients.

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The dimeric form of HIV-1 protease (PR) is required for its full proteolytic activity. The stability of the dimer primarily depends on the termini interface, with N-terminal residues 1–4 of one monomer encountering C-terminal residues 96–99 of another. We made an alanine substitution for valine 3 (V3) or leucine 97 (L97) at the termini dimer interface and tested their proteolytic activity. We found that an alanine substitution for L97 (PRL97A) completely inhibited the proteolytic activity of the PR. However, an alanine substitution for V3 (PRV3A) partially impaired the proteolytic activity. We then introduced two forced-dimerization systems involving nucleocapsid (NC) replacement or the addition of 1–2 leucine zippers to determine whether the proteolytic activity of dimer-defective PRs could be restored. We found that two forced-dimerization systems compensated for the defect in PRV3A, but not in PRL97A. This implies that PRV3A and PRL97A potentially impair the PR via different mechanisms or cause defects in PR activity to different extents. These novel findings will likely serve as a foundation for developing new PR inhibitors for treating drug-resistant HIV-1 infections in the future.

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Steroids are expected to be effective in the treatment of cytokine release syndrome, which is considered to be associated with severe cases of coronavirus disease 2019 (COVID-19). We aimed to investigate the use of steroids and its effects. We conducted a retrospective chart review and an analysis of 226 consecutive hospitalized patients with confirmed COVID-19. Patients were divided into those who received steroids (steroid group) and those who did not (no steroid group). Inverse probability weighted analysis was performed to assess the effect of steroids on in-hospital mortality. The steroid group had higher rates of preexisting hypertension and peripheral vascular disease as well as higher lactate dehydrogenase levels, d-dimer levels, and inflammatory markers than the no steroid group (all P <0.05). The steroid group had significantly higher rates of multifocal pneumonia than the no steroid group at admission (75.4% vs. 50.3%, P = 0.001). Notably, the steroid group had higher rates of developing bacterial infection (25% vs. 13.1%, P = 0.041) and fungal infection (12.7% versus 0.7%, P <0.001) during the hospital course than the no steroid group. After adjustment, it was observed that steroids did not decrease or increase in-hospital mortality (odds ratio [95% confidence interval]: 1.02 [0.60–1.73, P = 0.94]). There was an increase in bacterial and fungal infections with steroid use.

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This study assessed whether invasive group B Streptococcus (GBS) isolates were similar to non-invasive isolates from adult patients. Invasive and non-invasive GBS isolates were collected from three hospitals and two laboratory centers between January 2015 and October 2019. The isolates were identified by 16S rRNA amplicon sequencing and amplification of the GBS-specific dltS gene. The virulence gene profiles, capsular genotypes, sequence types (STs)/clonal complexes (CCs), and antimicrobial resistance (AMR) phenotypes/genotypes were determined for the 72 invasive and 50 non-invasive isolates that were comparatively analyzed. We observed a significantly decreased rate of rib detection in the invasive isolates compared to that in the non-invasive isolates (77.8% vs. 92.0%, P < 0.05). Additionally, we found significant differences in the prevalence of CC1 (23.6% vs. 46.0%, P < 0.05) and CC26 (12.5% vs. 2.0%, P < 0.05) between invasive and non-invasive populations. However, there were no significant differences in the comparative data of the virulence gene profiles, capsular genotypes, other STs/CCs, and AMR phenotypes/genotypes between the two populations. These findings suggest that both invasive and non-invasive isolates share similar features in terms of virulence gene profile, capsular genotype, ST/CC, and AMR genotype/phenotype (except for the rates of rib detection and CC1/CC26 prevalence).

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Studies describing reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay-based infection control strategies (LAMP-based ICSs) for coronavirus disease 2019 (COVID-19) are limited. We reviewed the medical records of cases in which RT-LAMP was performed. Standard ICSs and LAMP-based ICSs were implemented during the study period. The strategies were intended to impose longer periods of infection control precautions (ICPs) for specific patients, such as those with a history of exposure to COVID-19 patients and/or bilateral ground glass opacities (bGGO) on chest computed tomography (CT). Of 212 patients, which included 13 confirmed COVID-19 patients in the diagnostic cohort, exposure to COVID-19 patients (P <0.0001) and chest CT bGGO (P = 0.0022) were identified as significant predictors of COVID-19. In the 173 hospitalized patients in which the results of the first RT-LAMP were negative, the duration of ICPs was significantly longer in patients with exposure to COVID-19 and/or a high clinical index of suspicion and patients with bGGO than in the remaining patients (P = 0.00046 and P = 0.0067, respectively). Additionally, no confirmed COVID-19 cases indicating nosocomial spread occurred during the study period. Establishing a comprehensive system that combines rational LAMP-based ICSs with standard ICSs might be useful for preventing nosocomial spread.

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This study aimed to evaluate the infection rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among different populations in Wuhan, China. This cross-sectional survey-based study examined the results of SARS-CoV-2-specific serological tests and RT-PCR tests for 4,454 community residents and 4,614 healthcare workers performed from May 15 to May 29, 2020. The healthcare workers were classified as administrative and logistical staff (n = 1,378), non-first-line healthcare workers (n = 2,630), or first-line healthcare workers (n = 606) according to their frequency of contact with coronavirus disease (COVID-19) patients. The positive rates of SARS-CoV-2-specific IgG, IgM, and RNA were 2.9%, 0.4%, and 0.1% for the community residents and 3.3%, 0.6%, and 0.2% for the healthcare workers, respectively. There were no statistically significant differences between the rates of the two groups. Spearman’s correlation analysis showed that the frequency of contact with COVID-19 patients negatively correlated with the positive rates of RT-PCR (r_s = -0.036, P = 0.016), but did not significantly correlate with the positive rates of IgM (r_s = -0.006, P = 0.698) or IgG (r_s = 0.017, P = 0.239). There was no statistically significant difference between the SARS-CoV-2-specific IgG, IgM, or RNA positive rates of the community residents and those of the healthcare workers. The positive rate of SARS-CoV-2 RNA was lower for the first-line healthcare workers than for the non-first-line healthcare workers and the administrative and logistical staff.

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Following the 2018 rubella outbreak in Japan, this study aimed to assess rubella prevention measures based on the vaccination and immunization status of pregnant women in Japan. Our cohort study involved 3 local core hospitals in Yokohama City, and a total of 666 pregnant women were recruited between June 2018 and September 2019 and answered an online questionnaire. In total, 67.5% of the pregnant women had received rubella vaccination. The rate of rubella vaccination among pregnant women in the present survey was lower than that among age-matched female participants in a nationwide survey conducted in 2018. Overall, the study results showed that pregnant women in their 20s had a higher vaccination rate than those in their 40s, women who were nonsmokers before pregnancy had a higher vaccination rate than those who were smokers, and pregnant women who were aware that rubella may affect their fetuses had a higher vaccination rate than those who were unaware of this. This survey elucidated multiple predictive factors for rubella vaccination among pregnant women in Japan. Our results confirm the recommendation that women considering pregnancy should be vaccinated against rubella.

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Coronavirus disease 2019 (COVID-19) emerged in mid-December 2019 and has rapidly spread worldwide. We conducted a retrospective analysis of data from patients with COVID-19 to construct a simple risk prediction score to be implemented in prehospital settings. Patients were classified into critical and non-critical groups based on disease severity during hospitalization. Multivariate analysis was performed to identify independent risk factors and develop a risk prediction score. A total of 234 patients were included in the study. The median age of the critical group was significantly older than that of the non-critical group (68.0 and 44.0 years, respectively), and the percentage of males in the critical group was higher than that in the non-critical group (90.2% and 60.6%, respectively). Multivariate analysis revealed that factors such as age ≥ 45 years, male sex, comorbidities such as hypertension and cancer, and having fever and dyspnea on admission were independently associated with the critical COVID-19 infection. No critical events were noted in patients with a total risk factor score of ≤ 2. Contrastingly, patients with a total risk factor score ≥ 4 were more likely to have critical COVID-19 infection. This risk prediction score may be useful in identifying critical COVID-19 infections.

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Necrotizing pneumonia caused by Panton-Valentine leukocidin (PVL)-positive community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has high mortality rates and is currently a serious clinical issue. PVL is a two-component toxin (LukS-PV and LukF-PV). It can cause necrosis in target cells by forming pores consisting of an octamer comprised of LukS-PV and LukF-PV. However, considering the specificity of PVL towards several target cells and species, the specific effect of PVL remains controversial. Therefore, we focused on necrotizing pneumonia caused by PVL-positive S. aureus and clarified the effect of PVL on alveolar macrophages, which play a central role in innate immunity in the alveolar space. We constructed recombinant PVL (rPVL) components and stimulated alveolar macrophages isolated from rabbits to evaluate cytotoxicity and pro-inflammatory cytokine release. Recombinant LukS-PV (rLukS-PV), but not recombinant LukF-PV (rLukF-PV), induced pro-inflammatory cytokine release. Specifically, tumor necrosis factor (TNF)-α release was mediated by the C5a receptor (C5aR) expressed on rabbit alveolar macrophages, and the toxicity of rPVL, consisting of rLukS-PV and rLukF-PV, towards rabbit alveolar macrophages was mediated by the same receptor. Overall, our findings shed light on the C5aR-mediated cytotoxic effect of PVL on alveolar macrophages, which may be useful for understanding the mechanism of necrotizing pneumonia caused by PVL.

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This study aimed to develop and validate a bedside risk analysis system for predicting the clinical severity and prognosis of patients with coronavirus disease 2019 (COVID-19). In total, 444 COVID-19 patients were included and randomly assigned in a 2:1 ratio to 2 groups: derivation group and validation group. The new scoring system comprised of the following 8 variables: history of malignant diseases, history of diabetes mellitus, dyspnea, respiratory rate >24 breaths/min, C-reactive protein level >14 mg/L, white blood cell count >8×10⁹/L, platelets count <180 × 10¹²/L, and lymphocyte count <1 × 10⁹/L. The sensitivity analysis revealed that this new scoring system was more efficient than the sequential organ failure assessment scoring system on the first day of admission. The receiver characteristic curve analysis revealed that the new risk scoring predicted the severe cases of COVID-19 infection with an area under the curve of 0.831 (95% confidence interval [CI]: 0.783–0.879) and 0.798 (95% CI: 0.727–0.869) in the derivation and validation groups, respectively. This proposed risk score system is a fairly reliable and robust tool for evaluating the severity and prognosis of patients with COVID-19. This may help in the early identification of severe COVID-19 patients with poor prognosis, requiring more intense interventions.

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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently a major worldwide concern. Guidelines have been issued regarding precautions for healthcare workers caring for SARS-CoV-2-infected patients. Despite accurate observance of infection control measures, including contact precautions, we encountered an OXA-23-producing Acinetobacter baumannii outbreak in 5 intensive care units of 10 beds each in our tertiary care teaching hospital.

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Persistent high-risk (HR) human papillomavirus (HPV) infection is an essential risk factor for cervical carcinoma and precancerous lesion. There are differences in HPV distribution among different countries, regions and ethnic groups. The aim of this research was to reveal the epidemiological characteristics of HPV in Chongqing, China. In this study, 13,788 women aged 18 to 78 were screened for 23 HPV genotypes by PCR-reverse dot blot hybridization. The total HPV-positive rate was 19.9% (2,745/13,788), while the positive rates for HR, and low-risk (LR) HPV were 17.3% (2,379/13,788), and 4.6% (638/13,788), respectively. In addition to cervical cancer (CC) and cervical intraepithelial neoplasia (CIN) patients, the HPV infection rates among infertile women and women with gynecological diseases were markedly higher than that among healthy women. The HPV and HR-HPV infection rates in the different age groups showed statistically significant differences, and the prevalence peaks were observed in women under 20 years and over 50 years of age. Overall, HPV-52, HPV-16 and HPV-58 ranked as the top 3 most common subtypes among women in Chongqing. The results of this research provide epidemiological information regarding HPV infection in Chongqing. These data constitute valuable evidence for the prevention and management of cervical carcinoma and development of HPV vaccines.

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Multiple countries have reported evacuation missions to repatriate their citizens in the early phase of the emergence of COVID-19 from China. However, a paucity of data exists on how to optimally execute an evacuation while balancing the risk of transmission during the flight and avoiding spread to the evacuees’ home countries. We describe the collective findings of the flight evacuation mission from Wuhan, China to Tokyo, Japan from January 28 to February 17, 2020. The evacuation team established the evacuation processing flow, including a focused health questionnaire, temperature monitoring, ticketing and check-in, and boarding procedure planning. The evacuees were seated according to pre-planned zones. Additionally, to facilitate the triage of evacuees for medical needs, we conducted in-flight quarantine to determine the disposition of the evacuees. All evacuees, regardless of their health condition, were required to perform rigorous hand hygiene frequently and to wear surgical masks throughout the flight. We implemented strict infection prevention and control throughout the mission, including in-flight quarantine. The pre-planned protocol and vigilant observation during the flight were crucial elements of this mission. Our experience is of value in developing a more refined plan for the next outbreak.

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Soft tissue infections with Mycobacterium mageritense are uncommon. We report the case of a 5-year-old girl who developed a subcutaneous abscess in her right ankle caused by M. mageritense. She had a history of acute encephalopathy and adrenal insufficiency and was hospitalized for acute pancreatitis. During hospitalization, the patient developed fever and tachycardia. Blood culture was positive for gram-positive bacilli. Although initial testing with matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) reported a different organism, a repeat test identified M. mageritense. One month after the positive blood culture, she developed redness and swelling in the right ankle. The pus from the subcutaneous abscess after drainage grew M. mageritense, which was further confirmed by the sequencing of housekeeping genes. Based on sensitivity testing, the patient was treated with tosufloxacin and linezolid. The local inflammatory signs gradually improved on starting the treatment. The antibiotics were administered for 6 months, and she experienced no relapse during the 8 months of follow-up after the completion of therapy. This is the first case report of a pediatric M. mageritense infection, which also highlights an important potential pitfall of MALDI-TOF MS. Further, we observe that the choice of antimicrobials for the treatment of M. mageritense is more limited in children than in adults.

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Volume 74, no.3, p.214-219, 2021. Page 214, affiliation “¹TBA Co., LTD, Sendai; ²Hokkaido University Research Center for Zoonosis Control, Sapporo; ³Hokkaido University, GI-CoRE Global Station for Zoonosis Control, Sapporo; ⁴Zambia National Public Health Institute, Ministry of Health, Lusaka, Zambia; ⁵Department of Pathology and Microbiology, University Teaching Hospital Ministry of Health, Lusaka, Zambia; and ⁶Ministry of Health, Ndeke House, Lusaka, Zambia.” should read “¹TBA Co., LTD, Sendai, Japan; ²Hokkaido University Research Center for Zoonosis Control, Sapporo, Japan; ³Hokkaido University, GI-CoRE Global Station for Zoonosis Control, Sapporo, Japan; ⁴Zambia National Public Health Institute, Ministry of Health, Lusaka, Zambia; ⁵Department of Pathology and Microbiology, University Teaching Hospital Ministry of Health, Lusaka, Zambia; and ⁶Ministry of Health, Ndeke House, Lusaka, Zambia”.

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