Japanese Journal of Infectious Diseases

Influenza A/(H1N1)pdm09 virus evolves through continuous antigenic variation in both surface antigens such as hemagglutinin (HA) and neuraminidase (NA) proteins impacting pathogenicity, immune effectiveness and drug resistance. This study reports on evolution and dynamics of 527 HA protein sequences of influenza A/(H1N1)pdm09 Indian isolates submitted between the years 2009-2020. These isolates were aligned along with a reference sequence and 22 sequences representing different clades using MEGA X and subjected to phylogenic analyses...

Receptor interacting serine/threonine kinase (RIPK) 2 is associated with cellular inflammation and immune regulation. The current study explored the roles of RIPK2 in osteomyelitis and the potential upstream targets of RIPK2. S. aureus-induced osteomyelitis mouse model was established in the wide-type (WT) and ubiquitin specific peptidase 8 (USP8)-deficient (USP-/- ) mice and osteomyelitis-related symptoms were evaluated. Bone marrow-derived macrophages (BMDMs) were isolated from WT and USP-/- mice. ELISAs, qPCR, and immunoblot analysis were used to determine the levels of target biomarkers, which were induced by lipopolysaccharide (LPS), CpG or PAM3CSK4...

Mobile digital chest x-ray (CXR) is a commonly used method for pulmonary tuberculosis (PTB) screening among homeless people in the Nishinari District, Osaka City, Japan. We investigated mobile CXR screening (MCS) to calculate the case finding rate of culture-confirmed PTB among homeless examinees in the Nishinari District from 2013 to 2019. PTB was defined by sputum culture-confirmed cases. Examinees with culture-confirmed PTB more than 90 days after MCS were defined as no progression to active tuberculosis when undergoing MCS...

Sapovirus (SaV) and astrovirus (AstV) are important viral agents causing acute gastroenteritis. In this study, to determine the percentage of SaV and AstV as causative viruses of infectious gastroenteritis, we examined 53 samples of unknown cause from pediatric clinics in Kobe, Japan, where sentinel surveillance for infectious gastroenteritis was conducted from 2016 to 2019. SaV and AstV were screened for their presence by real-time PCR. Positive samples were genotyped by sequencing and genetic analysis of the partial regions of capsid and RdRp...

MenACYW-TT is a quadrivalent meningococcal tetanus toxoid-conjugate vaccine designed to prevent invasive meningococcal disease. The primary objective of this study was to demonstrate non-inferiority of the vaccine seroresponse to a single dose of MenACYW-TT compared to a licensed Meningococcal quadrivalent diphtheria-conjugate vaccine, MCV4-DT. This Phase III double-blind, multi-center study was conducted in meningococcal vaccine-naive participants aged 2-55 years in Japan (NCT04368429; JapicCTI-205288). Participants were randomized 1:1 to MenACYW-TT (n=180) or MCV4-DT (n=180)...

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a causative agent of SFTS. Although SFTS is a fatal tick-borne zoonosis, the virus can infect humans without tick bite exposure. Recently, direct SFTSV transmission from companion pets to humans has become a significant problem. Herein, we reported a case of SFTSV transmission from a dead community cat to a woman who buried the cat in Miyazaki prefecture, Japan. The community cat died without a diagnosis of SFTS, and the woman buried it without precaution...

We aimed to study the effects of methyltransferase 3 (METTL3) inhibitor on osteomyelitis in this study. Bone marrow cells (BMs) and peripheral blood mononuclear cells (PBMCs) were isolated. Primary BMs-derived macrophages (BMDMs) were incubated with lipopolysaccharide (LPS), poly (I: C), or PAM3CSK4 after pretreatment with STM2457. S.aureus was injected into the intramedullary canal to construct an osteomyelitis C57BL/6 mice model, which was further treated with STM2457. The body weight, μCT three-dimensional analysis, and bacterial burdens were obtained...

The development of human respiratory syncytial virus (HRSV) vaccine was hampered by an enhanced respiratory disease due to Th2-biased immune response. In this study, adjuvants MA103 and aluminum phosphate (Adju-Phos) were used to verify the immunogenicity of RBF protein (F protein expressed by E. coli). Both adjuvants significantly increased the neutralizing antibody titer and the number of IFN-γ-secreting CD4+ T cells in mice. However, from the IgG1/IgG2a and IFN-γ/IL-4-secreting CD4+ T cells ratio, MA103 significantly enhanced Th1-biased immune response...

In 2012, Escherichia fergusonii harboring heat-labile enterotoxin (LT) was isolated from healthy chickens in South Korea. However, little is known about the prevalence, spread, and pathogenicity of the strains for humans and animals. This study aimed to comprehend public health threats such as the distribution, antimicrobial resistance, and genetic diversity of E. fergusonii carrying LTs. E. fergusonii containing LT was isolated from 15.0% (52/346) of chicken fecal samples from all three farms but not from 360 pig samples...

Klebsiella oxytoca is an opportunistic pathogen that causes nosocomial infections. We describe an unusual clinical strain of indole-negative K. oxytoca, GU175, isolated from the urine of a patient with cystitis. The GU175 strain was identified as K. pneumoniae with a probability of 99.40%, negative for indole production, and resistant to third-generation cephalosporins by using the MicroScan Walkaway 40 SI system with the Negative combo EN1 J panel. Biochemical characterization of this strain using a lysine-indole motility medium was negative for indole production...

Twin pregnancy is often associated with adverse obstetric outcomes. Mother to child transmission of HIV in twin pregnancy is less explored. The present study aimed to determine the risk of vertical transmission of HIV in HIV exposed twin pregnancy in comparison to singleton and to explore associated factors. We conducted a retrospective cohort study involving 348 HIV exposed babies (58 twin and 290 singleton) through systematic sampling from program database of West Bengal, India from April 2016 to March 2021...

The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in late 2021 and gradually overtook the Delta variant, which was the predominant variant at that time. The Omicron variant has been consecutively replaced by related sublineages. The real-time RT-PCR assays developed by the National Institute of Infectious Diseases, Japan (i.e., the NIID-N2 and NIID-S2 assays) are the reference assays that have been used in Japan since the outbreak of SARS-CoV-2. To evaluate the applicability of the NIID assays for the Omicron variants, trends in the prevalence of nucleotide mismatches in the primer/probe sequences were traced using sequences registered in the Global Initiative on Sharing Avian Influenza Data database...

Antibiotic treatment is critical for gonorrhea-infected individuals and for preventing disease transmission. The aim of this study was to analyze the antimicrobial susceptibility and molecular epidemiological characteristics of Neisseria gonorrhoeae isolates in Changsha, China. A total of 271 N. gonorrhoeae isolates collected from clinical laboratories of two hospitals between 2016 and 2021 were analyzed for antimicrobial susceptibility using the agar dilution method. N. gonorrhoeae multi-antigen sequence typing (MG-MAST) was conducted for genotyping, and phylogenetic analysis was determined using porB and tbpB sequences...

Biosafety Level 4 (BSL-4) laboratories are necessary to study microorganisms that are highly pathogenic to humans and have no prevention or therapeutic measures. Currently, most BSL-4 facilities have suit-type laboratories to conduct experiments on highly pathogenic microorganisms. In 2021, the first Japanese suit-type BSL-4 laboratory was constructed at Nagasaki University. Positive pressure protection suit (PPPS) is a primary barrier that protect and isolate laboratory workers from pathogens and the laboratory environment...

We assessed biofilm production ability (BPA) of noninvasive Streptococcus dysgalactiae subsp. equisimilis (SDSE) from humans/companion animals and determined relationships between BPA populations and other host/microbiological features. Sixty-four companion animal-/human-origin isolates were collected with host information. We measured BPA using crystal violet staining, along with doing emm typing, multilocus sequence typing, and antimicrobial resistance (AMR) phenotyping/genotyping, and detection of virulence-associated genes (VAGs) (prtF1-prtF2-lmb-cbp-sicG-srtp1-srtp2-brpA)...

Burkholderia pseudomallei, the highly infectious causative organism of melioidosis, was first discovered in Myanmar in 1911. The identification of B. pseudomallei was elucidated in Myanmar because of its genetic relatedness among Burkholderia species. In this study, we identified 2 isolates of Burkholderia cenocepacia, 2 Acinetobacter baumannii complex, and 18 clinical isolates of B. pseudomallei by Vitek 2. These isolates were first screened with a latex agglutination test, which showed positive results in 20 of 22 isolates...

Penicillinase-producing Neisseria gonorrhoeae (PPNG) possessing blaTEM-135 is a serious public health threat. With only a single change in amino acid sequence, blaTEM-135 could evolve into TEM-type extended-spectrum beta-lactamase (ESBL), which hydrolyzes extended-spectrum cephalosporins, including ceftriaxone and cefixime. We investigated the molecular epidemiological characteristics, types of plasmids of PPNG isolates, and prevalence of PPNG clinical isolates producing TEM-135 beta-lactamases. N. gonorrhoeae multiantigen sequence typing (NG-MAST) was used to determine the molecular epidemiological characteristics of 99 PPNG isolates collected from 2015 to 2017...

Plastic bronchitis (PB) is a rare and severe respiratory disease characterized by the formation of branching mucus casts, resulting in airway obstruction. PB can be divided into two types. Type 1 PB is primarily due to inflammatory casts caused by allergic diseases. In type 2 PB, mucinous casts are produced in association with congenital heart diseases. PB is also associated with viral respiratory infections, particularly influenza A (H1N1) pdm09 virus, which is the most common pathogen affecting pediatric patients...

Invasive aspergillosis (IA) is an important cause of morbidity and mortality. In this study, we aimed to present our 10-year IA experience in a single center. Fifty-nine pediatric patients diagnosed with IA were included in the study. The male/female ratio of these patients was 42/17. The median age was 8.75 years. Hematologic malignancy was present in the majority of the patients (40/59, 68%). The mean duration of neutropenia was 18.5 days. Cytosine arabinoside was the most common immunosuppressive therapy directed at T-cells at the time of IA diagnosis...

The treatment of severe hemorrhagic fever with renal syndrome (HFRS) cases is difficult.We lack an early warning model for severe HFRS patients today. We retrospectively collected the data of 235 HFRS patients from January 2013 to December 2019, as well as 394 laboratory indicators. The multivariate logistic regression model was used to construct an early warning model for severe disease. The accuracy of the model was evaluated based on the area under the receiver operating characteristic (ROC) curve. The area under curve (AUCs) of the early warning models both exceeded 0...