Journal of Infectious Diseases最新文献

Background: Hemagglutinin (HA)-inhibiting antibodies contribute to the immune defense against influenza infection. However, there are insufficient data on the extent of correlation between vaccine-elicited HA antibodies and protection in children against different influenza strains, particularly when comparing live attenuated influenza vaccines (LAIV) versus inactivated influenza vaccines (IIV).

Methods: We measured postvaccination hemagglutination-inhibition (HAI) titers in 3-15-year-old participants of a cluster-randomized controlled trial of trivalent LAIV(3) versus IIV(3) in Canadian Hutterite colonies. We assessed HAI titers as predictors of symptomatic, reverse transcription polymerase chain reaction (RT-PCR)-confirmed influenza over 3 influenza seasons using Cox proportional hazards regression models with vaccine type as a covariate.

Results: For each log2 unit increase in postvaccination HAI against A/H1N1 in 2013-2014, A/H3N2 2014-2015, and B/Yamagata in 2013-2014 (each the predominant circulating strain for the respective influenza season), the reduction in the risk of confirmed influenza was equal to 29.6% (95% confidence interval [CI], 17.1%-39.5%), 34.8% (95% CI, 17.2%-47.9%), and 31.8% (95% CI, 23.8%-38.5%), respectively. No reduction in the risk of influenza was observed with B/Yamagata-specific HAI titers in 2012-2013, which was dominated by a mixture of Yamagata and Victoria strains. Despite the overall lower HAI titers in the LAIV3 group, both H1N1 and H3N2 HAI titers were associated with protection against subtype matched influenza.

Conclusions: Both LAIV3- and IIV3-elicited HA antibodies are associated with protection against influenza infection in seasons when the vaccine strains match the circulating influenza strain subtypes, supporting the use of HAI as a correlate of protection for both vaccine types in children.

Severe fever with thrombocytopenia syndrome (SFTS) is a highly fatal disease. Droplet digital polymerase chain reaction (ddPCR) presents unparalleled sensitivity and enables absolute quantification of viral load. In this prospective study, we enrolled 111 patients with SFTS and collected 259 continuous samples. Our findings unveil a robust reverse transcription (RT)-ddPCR method for SFTS with a limit of detection of 2.46 copies/µL (95% CI, 1.50-11.05), surpassing the sensitivity of RT-quantitative polymerase chain reaction at 103.29 copies/µL (95% CI, 79.69-216.35). Longitudinal cohort analysis revealed significantly higher RT-ddPCR detection rates at days 10 to 11, 13 to 14, and ≥15 of the disease course as compared with RT-quantitative polymerase chain reaction (P < .05). Positive RT-ddPCR results were associated with declined platelet and elevated aspartate aminotransferase and lactate dehydrogenase on the same day vs negative RT-ddPCR samples. RT-ddPCR exhibits commendable diagnostic efficacy in SFTS, and it remains detectable in blood samples from patients with an extended disease course. Furthermore, RT-ddPCR correlates with clinical laboratory tests, furnishing valuable reference data for clinical diagnosis.

Background: By acting as an environmental sensor, the ligand-induced transcription factor aryl hydrocarbon receptor (AhR) regulates acute innate and adaptive immune responses against pathogens. Here, we analyzed the function of AhR in a model for chronic systemic infection with attenuated Salmonella Typhimurium (STM).

Methods: Wild type and AhR-deficient mice were infected with the attenuated STM strain TAS2010 and analyzed for bacterial burden, host defense functions, and inflammatory stress erythropoiesis.

Results: AhR-deficient mice were highly susceptible to TAS2010 infection when compared with wild type mice, as demonstrated by reduced bacterial clearance and increased mortality. STM infection resulted in macrocytic anemia and enhanced splenomegaly with destruction of the splenic architecture in AhR-deficient mice. In addition, AhR-deficient mice displayed a major expansion of splenic immature red blood cells, indicative of infection-induced stress erythropoiesis. Elevated serum levels of erythropoietin and interleukin 6 upon infection, as well as increased numbers of splenic stress erythroid progenitors already in steady state, probably drive this effect and might cause the alterations in splenic immune cell compartments, thereby preventing an effective host defense against STM in AhR-deficient mice.

Conclusions: AhR-deficient mice fail to clear chronic TAS2010 infection due to enhanced stress erythropoiesis in the spleen and accompanying destruction of the splenic architecture.

Background: Between 2016 and 2023, 3248 cases of circulating vaccine-derived type 2 poliomyelitis (cVDPV2) were reported globally and supplementary immunization activities (SIAs) with monovalent type 2 oral poliovirus vaccine (mOPV2) and novel type 2 oral poliovirus vaccine (nOPV2) targeted an estimated 356 and 525 million children, respectively. This analysis estimates the community-level impact of nOPV2 relative to mOPV2 SIAs.

Methods: We fitted interrupted time-series regressions to surveillance data between January 2016 and November 2023 to estimate the impact of nOPV2 and mOPV2 SIAs on cVDPV2 poliomyelitis incidence and prevalence in environmental surveillance across 37 countries, directly comparing the impact of SIAs in 13 countries where both vaccines were used.

Results: We did not find any statistically significant differences between nOPV2 and mOPV2 SIA impact except for in the Democratic Republic of Congo (DRC), where nOPV2 SIAs had lower impact (adjusted relative risk [aRR] for cVDPV2 poliomyelitis incidence per nOPV2 SIA, 0.505; 95% confidence interval [CI], .409-.623) compared to mOPV2 (aRR, 0.193; 95% CI, .137-.272); P value for difference in RRs = 3e-6.

Conclusions: We find variation in OPV2 SIA impacts globally, with greater certainty about Nigeria and DRC, where large outbreaks provided an opportunity to assess impact at scale. In most countries, we find no significant difference between nOPV2 and mOPV2 SIA impact. We are unable to identify the reason for the significant difference in DRC, which could include differential SIA coverage, timing, vaccine effectiveness, or outbreak dynamics.

Background: Surgical site infection (SSI) is a common and costly complication in spinal surgery. Identifying risk factors and preventive strategies is crucial for reducing SSIs. Generative Pre-trained Transformer 4 (GPT-4) has evolved from a simple text-based tool to a sophisticated multimodal data expert, invaluable for clinicians. This study explored GPT-4's applications in SSI management across various clinical scenarios.

Methods: GPT-4 was employed in clinical scenarios related to SSIs in spinal surgery. Researchers designed specific questions for GPT-4 to generate tailored responses. Six evaluators assessed the responses for logic and accuracy using a 5-point Likert scale. Interrater consistency was measured with Fleiss' kappa, and radar charts visualized GPT-4's performance.

Results: Interrater consistency, measured by Fleiss' kappa, ranged from 0.62 to 0.83. The average scores for logic and accuracy were 24.27 ± 0.4 and 24.46 ± 0.25. Radar charts indicated consistently high performance across criteria. GPT-4 demonstrated proficiency in creating personalized treatment plans, improving SSI management strategies, and identified emerging research trends.

Conclusions: GPT-4 shows a significant potential in SSI management in spinal surgery, promoting patient-centered care and precision medicine. Despite limitations in antibiotics and patient education, GPT-4's continuous learning, data privacy focus, and professional collaboration indicate its potential to revolutionize SSI management, requiring further development.

Background: Understanding factors affecting the infectiousness of influenza cases is crucial for disease prevention and control. Viral shedding is expected to correlate with infectiousness of cases, but it is strongly associated with age and the presence of symptoms.

Methods: To elucidate this complex interplay, we analyze with an individual-based household transmission model a detailed household transmission study of influenza with 442 households and 1710 individuals from 2008 to 2017 in Hong Kong, to characterize the household transmission dynamics and identify factors affecting transmissions.

Results: We estimate that age, fever symptoms, and viral load were all associated with higher infectiousness. However, by model comparison, the best model included age and fever as factors affecting individual infectiousness, and estimates that preschool and school-aged children were 317% (95% credible interval [CrI], 103%, 1042%) and 161% (95% CrI, 33%, 601%) more infectious than adults, respectively, and patients having fever had 146% (95% CrI, 37%, 420%) higher infectiousness. Adding heterogeneity on individual infectiousness of cases does not improve the model fit, suggesting these factors could explain the difference in individual infectiousness.

Conclusions: Our study clarifies the contribution of age, symptoms, and viral shedding to individual infectiousness of influenza cases in households.

Recurrence is a rare complication of group B Streptococcus (GBS) neonatal infections. We conducted a retrospective observational study on GBS neonatal invasive infections in France from 2007 to 2021. A total of 1527 cases were reported, of which 36 (2.36%) were recurrent. Recurrence mainly concerned preterm (68%) and low-birth-weight (72%) infants and was associated with the hypervirulent GBS clonal complex 17 (83%; odds ratio, 2.86 [95% confidence interval, 1.18-6.92]). No β-lactam-tolerant strains were identified, and bacterial whole-genome sequencing could not reveal any specific feature associated with recurrence. Large-cohort studies should be undertaken to address the optimal management of these uncommon diseases.

Background: The role of 2-deoxy-2-18(F) fluoro-D-glucose (FDG) positron emission tomography (PET)-computed tomography (CT) in assessing treatment response in chronic pulmonary aspergillosis (CPA) remains to be determined. The study objective was to compare FDG-PET/CT parameters in persons with CPA achieving treatment success or failure after 6 months of oral itraconazole.

Methods: We performed PET-CT at baseline and after 6 months of oral itraconazole therapy. FDG uptake similar to the background uptake or ≥13 units decline in Z-score was considered a complete metabolic response (CMR). A >25%, >30%, and > 45% decline in standardised uptake value (SUVmax), SUVpeak, and total glycolytic activity (TLG) was labelled as a partial metabolic response (PMR). A >30%, >30%, or >75% increase in the SUVmax, SUVpeak, and TLG represented progressive metabolic disease.

Results: We included 94 persons with CPA (63 male) with a mean age of 46.2 years. A follow-up PET-CT was performed on 77 participants. We recorded treatment success and failure in 43 and 34 patients. CMR was seen in 18.6% of those with treatment success and none with treatment failure. A higher proportion of patients with treatment success achieved PMR; 19% of the patients with treatment success had progressive metabolic disease.

Conclusions: Most PET-CT parameters improved with treatment; however, PET-CT misclassified one-fifth of the participants.