RESUMEN
This study aimed to elucidate the 12-month durability of neutralizing antibodies (NAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in patients infected during the 2020 workplace outbreaks of coronavirus disease 2019 (COVID-19) in Japan. We followed 33 Japanese patients infected with SARS-CoV-2 in April 2020 for 12 months (12M). Patients were tested for NAbs and for antibodies against the SARS-CoV-2 nucleocapsid (anti-NC-Ab) and antibodies against the spike receptor-binding domain (anti-RBD-Ab). Tests were performed at 2M, 6M, and 12M after the primary infection (api) with commercially available test kits. In 90.9% (30/33) of patients, NAbs persisted for 12M api, though the median titers significantly declined from 78.7% (interquartile range [IQR]: 73.0-85.0%) at 2M, to 59.8% (IQR: 51.2-77.9) at 6M (P = 0.008), and to 56.2% (IQR: 39.6-74.4) at 12M (P<0.001). An exponential decay model showed that the NAb level reached undetectable concentrations at 35.5 months api (95% confidence interval: 26.5-48.0 months). Additionally, NAb titers were significantly related to anti-RBD-Ab titers (rho = 0.736, P<0.001), but not to anti-NC-Ab titers. In most patients convalescing from COVID-19, NAbs persisted for 12M api. This result suggested that patients need a booster vaccination within one year api, even though NAbs could be detected for over two years api. Anti-RBD-Ab titers could be used as a surrogate marker for predicting residual NAb levels.
Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Formación de Anticuerpos , COVID-19/epidemiología , Brotes de Enfermedades , Humanos , Japón/epidemiología , Glicoproteína de la Espiga del Coronavirus , Lugar de TrabajoRESUMEN
OBJECTIVES: Human parechovirus (HPeV), especially HPeV A3 (HPeV3), causes sepsis-like diseases and sudden infant death syndrome in neonates and young infants. Development of rapid and easier diagnostic laboratory tests for HPeVs is desired. METHODS: Original inner primers, outer primers, and loop-primers were designed on the 5' untranslated region of HPeV3. HPeV3 ribonucleic acids (RNAs), other viral RNAs, and clinical stool samples were used to confirm whether the designed primers would allow the detection of HPeV3 with the reverse transcription loop-mediated isothermal amplification (RT-LAMP) technique. RESULTS: Three combinations of primers were created and it was confirmed that all primer sets allowed the detection of HPeV3 RNAs. The primer sets had cross-reactivity with HPeV type 1 (HPeV1), but all sets showed negative results when applied to coxsackievirus, echovirus, enterovirus, norovirus, and adenovirus genomes. Four of six stool samples, obtained from newborn and infant patients with sepsis-like symptoms, showed positive results with our RT-LAMP technique. CONCLUSIONS: This manuscript is the first description of an RT-LAMP for the diagnosis of HPeVs, allowing a faster, easier, and cheaper diagnosis. This technique is clinically useful for newborns and infants who have sepsis-like symptoms.
Asunto(s)
Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Parechovirus/aislamiento & purificación , Infecciones por Picornaviridae/diagnóstico , Humanos , Lactante , Recién Nacido , Técnicas de Diagnóstico Molecular/economía , Técnicas de Amplificación de Ácido Nucleico/economía , Parechovirus/genética , Infecciones por Picornaviridae/virología , ARN Viral/análisis , ARN Viral/genética , Sensibilidad y Especificidad , Factores de TiempoRESUMEN
Japan has reported 26 cases of coronavirus disease 2019 (COVID-19) linked to cruise tours on the River Nile in Egypt between March 5 and 15, 2020. Here, we characterized the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome of isolates from 10 travelers who returned from Egypt and from patients possibly associated with these travelers. We performed haplotype network analysis of SARS-CoV-2 isolates using genome-wide single-nucleotide variations. Our analysis identified two potential Egypt-related clusters from these imported cases, and these clusters were related to globally detected viruses in different countries.
RESUMEN
Seven cases of Streptococcus suis infection in Japan during 1994 and 2006 were summarized. All cases had porcine exposure and five of them had hand skin injury during the exposure. Five cases presented symptoms of meningitis, three presented symptoms of sepsis, and one resulted in sudden death. All of the isolated S. suis belonged to Lancefield's group D and to serotype 2. They were susceptible to penicillin G, ampicillin, cefotaxime, and ciprofloxacin. However, six of them were resistant to both erythromycin and clindamycin, and four were also resistant to minocycline. Multilocus sequence typing of six isolates showed that they belonged to sequence type (ST) 1, and their pulsed-field gel electrophoresis (PFGE) patterns were similar. The remaining isolate was ST28 and its PFGE pattern was distinct from those of the others.
Asunto(s)
Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/fisiopatología , Streptococcus suis/clasificación , Streptococcus suis/aislamiento & purificación , Porcinos/microbiología , Zoonosis/transmisión , Animales , Antibacterianos/farmacología , Técnicas de Tipificación Bacteriana , ADN Bacteriano/análisis , Electroforesis en Gel de Campo Pulsado , Femenino , Humanos , Japón/epidemiología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Serotipificación , Infecciones Estreptocócicas/microbiología , Streptococcus suis/efectos de los fármacos , Streptococcus suis/genética , Enfermedades de los Porcinos/microbiología , Enfermedades de los Porcinos/transmisión , Zoonosis/microbiologíaRESUMEN
Diarrheagenic Escherichia coli are differentiated from non-pathogenic members with enterotoxin production, enteroinvasiveness and serotyping. However, the serotypic members are rarely sufficient to reliably identify a strain as diarrheagenic on E. coli. Recently, there are many definite articles which the adhesive E. coli strain against intestinal epithelial cells is enterovirulent. In this study, 1,748 E. coli isolates of diarrheagenic and non-diarrheagenic categories which belonged to EHEC, ETEC, EIEC EPEC and non-EPEC were examinated by PCR method for the presence of eaeA, aggR and bfpA regarding adherence factor genes, and astA of EAST1. The strains examined were recognized to variable carrying geno-patterns, and a large number of EHEC, EPEC and non-EPEC had carried either eaeA or aggR genes. In EHEC isolates, a carrying pattern with the most high frequency was only eaeA, and this type was recognized in the isolates of serotype O157, O26 and O111. EPEC and non-EPEC isolates were recognized eaeA or aggR which harboring with astA or not. Of 508 EPEC isolates from human, a total of 137 isolates (27.0%) carried aggR, and a total of 74 isolates (14.6%) had eaeA, while of the 91 isolates from non-human were recognized aggR and eaeA with 2.2% (2 isolates) and 12.1% (11 isolates), respectively. Also, of 266 non-EPEC isolates from human, a total of 16 isolates (6.0%) carried aggR, and a total of 58 isolates (21.8%) had eaeA. On the other hand, 22 (7.0%) of 316 isolates examined from non-human had eaeA, however no isolate had aggR. Thirteen isolates of EIEC and 218 ETEC isolates were screened, and only 6 ETEC isolates had either eaeA or aggR. The astA gene was recognized in the isolates of all categories, and ETEC strains had more frequently. The bfpA gene was recognized with more frequently in a serotype O157: H45, which is obtained from human with diarrhea, however, this strain was not recognized a member of the EPEC serotype. There is no diagnostic system for the strain of E. coli that cause diarrheal diseases, therefore more laboratories are unable to identify them. The authors had confirmed which PCR technique is a useful simple and rapid method for the detection of adherence factor genes on E. coli strains. From the these results, we showed a differentiation method using PCR technique which have relation with adherence factor, enterotoxin-production and invasiveness, and we firmly believe that application of the procedure is a reasonable and useful method for the identification of diarrheagenic E. coli.