In this study, we compared the predictive performances of quick sequential organ failure assessment (qSOFA), the acute physiology and chronic health evaluation (APACHE II) scores, and the severity grading score (SGS) for evaluation of the disease prognosis of patients with Crimean-Congo hemorrhagic fever (CCHF) at the emergency department. We recorded the qSOFA, SGS, and APACHE II scores at admission and at the 72nd and 120th hour in 97 patients admitted to the emergency department and diagnosed with CCHF. In our study, the area under a receiver operating characteristic curve values of qSOFA, SGS, and APACHE II at admission were found to be 0.640, 0.824, and 0.576, respectively. No statistical significance was found for a qSOFA score ≥ 2 at admission as a predictor of mortality. The use of qSOFA score for diseases with a mortal prognosis such as CCHF is insufficient in predicting the prognosis.

Scrub typhus (ST) is a mite-borne rickettsiosis caused by the intracellular bacterium Orientia tsutsugamushi (OTS), which is classified as a biosafety level-3 (BSL-3) pathogen. For serological tests of ST, mouse fibroblast cells infected with the five prevalent serotypes of OTS in Japan are generally used as antigens for indirect immunofluorescence assay (IFA). In this study, Spodoptera frugiperda derived insect cell line (Sf9) cells infected with recombinant type-specific antigen (rTSA)-expressing baculovirus were used for IFA. The paired serum samples of 15 ST patients, 10 rickettsiosis patients, and 10 control individuals were used. IgM and IgG titers determined by the rTSA-based IFA were correlated with those determined by the OTS-infected cell-based IFA (R² = 0.7319 to 0.7956). Based on the criteria for serological diagnosis, such as a suitable cutoff for single serum samples (IgM ≥ 1:160) and/or a significant increase in IgG titers between paired sera (≥ 4-fold), all 15 ST patients diagnosed as positive with the OTS-infected cell-based IFA were also diagnosed as positive by the rTSA-based IFA, whereas all 10 rickettsiosis patients and 10 control individuals were not. Thus, the rTSAs, which can be prepared in BSL-2 laboratories, are efficacious for the serological diagnosis of ST.

In Indonesia, the highly pathogenic avian influenza A/H5N1 virus has become endemic and has been linked with direct transmission to humans. From 2013 to 2014, we isolated avian influenza A/H5N1 and A/H3N6 viruses from poultry in Indonesia. This study aimed to reveal their pathogenicity in mammals using a mouse model. Three of the isolates, Av154 of A/H5N1 clade 2.3.2.1c, Av240 of A/H5N1 clade 2.1.3.2b, and Av39 of A/H3N6, were inoculated into BALB/c mice. To assess morbidity and mortality, we measured body weight daily and monitored survival for 20 d. Av154- and Av240-infected mice lost 25% of their starting body weight by day 7, while Av39-infected mice did not. Most of the Av154-infected mice died on day 8, while the majority of the Av240-infected mice survived until day 20. A 50% mouse lethal dose was calculated to be 2.0 × 10¹ 50% egg infectious doses for Av154, 1.1 × 10⁵ for Av240 and > 3.2 × 10⁶ for Av39. The Av154 virus was highly virulent and lethal in mice without prior adaptation, suggesting its high pathogenic potential in mammals. The Av240 virus was highly virulent but modestly lethal, whereas the Av39 virus was neither virulent nor lethal. Several mammalian adaptive markers of amino acid residues were associated with the highly virulent and lethal phenotypes of the Av154 virus.

The serogroups O1 and O139 of the marine bacterium Vibrio cholerae are responsible for causing cholera in humans. The pentose sugar arabinose is nonmetabolizable by the pathogen and is present in environmental niches as well as in the human intestine. In this study, arabinose-mediated V. cholerae growth interference was assessed in M9 minimal medium containing gluconate as the sole carbon source in the light of Entner-Doudoroff (ED) pathway, an obligatory metabolic route for gluconate utilization. V. cholerae O1 and O139 strains failed to grow in the presence of ≥ 0.3% arabinose in M9 with 0.2% gluconate, but there was no growth inhibition in the presence of arabinose in M9 with 0.2% glucose. Transcriptional analysis of edd and eda, the genes constituting the ED pathway, showed ~100- and ~17-fold increases, respectively, in M9-gluconate. Minor increases of ~4- and ~2-fold for edd and eda, respectively, were noted in AKI medium supplemented with 0.5% arabinose. The observed arabinose-mediated growth inhibition can contribute toward deepening the understanding of altered phenotypes, if any, via complementation/expression studies in V. cholerae with pBAD vectors and arabinose as an inducer.

Seven human mastadenovirus (HAdV) species (A–G) are known with more than 100 reported types. HAdV is highly resistant to common hand sanitizers. Epidemic keratoconjunctivitis and pharyngoconjunctival fever are caused by HAdV, which can be explosively transmitted in a confined space, resulting in outbreaks, such as nosocomial infections. Given the absence of an antiviral agent against the HAdV infection, it is important to prevent the spread of the infection by using disinfectants. Ozone has already been well-known for its bactericidal and virucidal effects. ALTANT is an ozonated alcohol preparation developed by E-TECH Co., Ltd. (Kobe, Hyogo, Japan). In this study, we mixed ALTANT with different HAdV types at a ratio of 9:1 and determined HAdV viability after instantaneous reactions for varying periods (flash to 5 minutes) using the TCID50 assay. The assay results demonstrated that the HAdV viability decreased by 1/10 to 1/100 within 1 minute after the reaction; additionally, slight differences in the reactivity were observed among the HAdV types. HAdV viability decreased by a factor of > 4log₁₀, and the virus was eliminated within 3 minutes. This study demonstrated the potent HAdV disinfection effect of ALTANT.

Emergence and spread of multidrug-resistant organisms (MDRO) is an urgent social and public health problem. Here, we carried out an epidemiological survey to clarify the geographical characteristics and factors influencing the prevalence of MDRO. Data on the prevalence of MDRO in 47 prefectures in Japan were extracted from the Japanese Nosocomial Infection Surveillance, a nationwide database for infection control. Potential factors for MDRO were analyzed using data selected from the pharmacological, medical service, infection control, environmental, social, and food-related categories, based on the characteristics of each organism and the correlations between them and MDRO prevalence. Statistical data for potential factors were obtained from public domains. The use of antibiotics was found to be correlated with the prevalence of penicillin-resistant Streptococcus pneumoniae, 3rd-generation cephalosporin- and fluoroquinolone-resistant Escherichia coli, and methicillin-resistant Staphylococcus aureus. Negative correlation between the consumption of food such as kelp and fermented soybeans that facilitate the growth of lactic acid bacteria and the prevalence of 3rd-generation cephalosporin- and fluoroquinolone-resistant E. coli suggested an association between the intestinal microflora and MDRO colonization. In addition to the use of antibiotics, lifestyle, food culture, and social factors such as tobacco smoking, average atmospheric temperature, prevalence of three-generation households, ratio of elderly population, average duration of tourist stay, chicken and fermented soybean consumption, and the competency of healthcare services may also affect MDRO prevalence.

We report the first detection of a macrolide-resistant Bordetella pertussis strain in Japan. The isolate was highly resistant to the macrolides (minimum inhibitory concentrations for erythromycin and clarithromycin: > 256 µg/ml, for azithromycin: 32 µg/ml) and A2047G mutation was identified in the 23S rRNA. The Multilocus Sequence Typing and Multilocus Variable Number of Tandem Repeat Analysis genotypes of this isolate were MT195 and ptxP1/ptxA1/prn1/fim3A/fhaB3, respectively, suggesting a relationship with the macrolide-resistant B. pertussis lineage currently found in China. This raises the possibility that macrolide-resistant B. pertussis has already fully spread in Japan. For a better control of B. pertussis infections, the surveillance for macrolide-resistant B. pertussis is essential in not only Japan, but also other Asian countries.

In this study, we investigated four clinical cases of microbial contamination of in-use intravenous infusion fluid, detected by measuring “Adenosine triphosphate (ATP) + adenosine monophosphate (AMP)” (“ATP+AMP”) levels. High “ATP+AMP” values correlate with microbial contamination, and by utilizing these values as indicator for microbial contamination possibility, we were able to rapidly detect the contamination and recommend replacement of catheters and administration sets. In three out of four cases, changing the infusion fluid led to improvement in the condition of the patients. “ATP+AMP” levels can be used to confirm microbial contamination of in-use intravenous infusion fluids, as it is fast (several minites) and convenient to measure them.

The coronavirus induced disease 2019 (COVID-19) outbreak caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Wuhan (China) in December 2019 is currently spreading rapidly worldwide. We recently reported a laboratory protocol for the diagnosis of SARS-CoV-2 based on real-time reverse transcriptase PCR (RT-PCR) assays using two primer sets, N and N2. On January 30–31, 2020, the protocol and the reagents for these assays were distributed to the local public health institutes and quarantine depots in Japan nationwide, and thereafter SARS-CoV-2 diagnostic testing was initiated. For further validation, the assays were compared with the commercially available kits using the SARS-CoV-2 viral RNA and clinical specimens obtained from COVID19-suspected individuals. The LightMix Modular SARS and Wuhan CoV E-gene (LM S&W-E) assay was highly sensitive for the SARS-CoV-2, as was the N2 set, as both the assays showed consistent results for the clinical specimens. While the LM S&W-E set targets the highly conserved region of E gene in the SARS-CoV and SARS-CoV-2, the N2 set was designed to target specifically the unique region in the SARS-CoV-2 N gene. Therefore, the N2 set exhibits high specificity and sensitivity for SARS-CoV-2 detection. These results indicate that the protocol using the N and N2 sets is comparable to the commercially available kits, and thus is reliable for laboratory diagnosis of COVID-19.

We report the second case of deceased donor liver transplantation in a patient co-infected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) in Japan. A 48-year-old patient with hemophilia A was infected with HIV and HCV through contaminated factor VIII concentrate in his childhood and developed cirrhosis and hepatocellular carcinoma. The patient was on the transplant list for a deceased donor liver. The patient had broad spectrum anti-HLA class I and II antibodies, which may be attributed to repeated whole blood transfusions in the past. Catastrophic coagulopathy during the surgery was predicted because of the underlying hemophilic status and severe thrombocytopenia requiring HLA-matched platelet products, which are difficult to obtain quickly. To maintain adequate platelet counts (> 5 × 10⁴/µL) while awaiting liver transplantation, a thrombopoietin receptor agonist and rituximab were administered. During surgery, factor VIII concentrate was administered according to a previously planned protocol. Adequate hemostasis was obtained, and the operation was completed without uncontrollable coagulopathy. The postoperative course was uneventful, and the patient was discharged on postoperative day 41. Detailed planning is required for surgical patients with hemophilia and HIV/HCV cirrhosis, especially for those with a diverse spectrum of anti-HLA antibodies.

We report a case of non-necrotizing soft tissue infection and streptococcal toxic shock syndrome (STSS) caused by a novel emm subtype (emm76.10) of group A Streptococcus pyogenes (GAS). A 54-year-old Japanese woman suffering from fever, fatigue, and lower abdominal pain along with erythema for 3 days was admitted to our hospital. Additionally, she presented with hypotension and multiple organ failure. Exploratory incision was performed due to the presence of STSS and for an examination of the necrotizing soft tissue infection from her lower abdomen to the left thigh. Tissue cultures from the exudates and fascia yielded positive results for GAS growth, although blood cultures returned as negative. After 15 days of antimicrobial therapy, she recovered fully without any complications. Genotyping of the isolate indicated a novel emm subtype (emm76.10), with 5 amino acid substitutions in the emm76.0 subtype sequence and the full-length sequence of 780 bp. This isolate was resistant to tetracyclines, macrolides-lincosamides, and fluoroquinolones, owing to the presence of antibiotic resistance determinants, tet(M) and erm(B), and point mutations, Ser79Phe/Ser81Phe, in the quinolone resistance-determining regions of parC/gyrA. In conclusion, our observations suggest the importance of early-stage exploratory incision and drainage from the infected region for the isolation and characterization of causative bacteria to facilitate selection of appropriate antibiotics for treatment.

Coronavirus disease 2019 (COVID-19) is a severe infectious disease of the respiratory tract caused by a novel coronavirus, severe acute respiratory syndrome coronavirus 2, and has a high mortality rate. The disease emerged from Wuhan, China, in late 2019, and spread to Japan, including Hokkaido, in January 2020. In February 2020, 3 children were diagnosed with COVID-19 in Furano, Hokkaido, Japan. During this period, influenza and human metapneumovirus infections were prevalent among children in the Furano region. Two of the 3 patients experienced co-infection with other respiratory viruses, including influenza virus A or human metapneumovirus. To the authors’ knowledge, the cases described in the present report were the first pediatric patients with COVID-19 in Japan. In children with COVID-19, the possibility of co-infection with other respiratory pathogens should be considered.

Japanese encephalitis (JE) is a clinical disease caused by inflammation of the central nervous system. The symptoms of this disease range broadly in severity from mild febrile illness to acute meningomyeloencephalitis. JE has been associated with a variety of neurological abnormalities, such as altered sensorium, seizures, focal neurological deficit, and acute flaccid paralysis (AFP). However, to date, AFP has never been reported as an initial manifestation of JE. Here, we present a case of AFP manifesting as the initial symptom of JE in a Chinese patient. A 30-year-old Chinese man was admitted to the West China Hospital of Sichuan University after experiencing AFP in the right upper limb, followed by hyperpyrexia and unconsciousness. Assay of cerebrospinal fluid from a lumbar puncture revealed high levels of proteins and anti- JE virus IgM antibodies. Intravenous acyclovir was administered; however, the weakness persisted and more extensive muscle wasting from the proximal to distal right upper limb occurred over 7 months. This case report highlights that JE needs to be added to the differential diagnosis of AFP in adults, especially in JE endemic seasons and areas.