Clinical Infectious Diseases最新文献

The concept of immunity debt is a phenomenon resulting from the suppression of endemic pathogens during the COVID-19 pandemic due to non-pharmaceutical interventions. The reduced circulation of various pathogens during the pandemic, particularly respiratory syncytial virus (RSV), altered typical infectious disease dynamics by reducing levels of population immunity usually acquired through exposure to infection. This concept is demonstrated through the post-pandemic resurgence of diseases such as RSV and group A Streptococcus, and highlights the interplay between reduced pathogen exposure and increased susceptibility in populations. The complexities and nonlinear dynamics of seasonal transmission are observed in differences in pathogen resurgence across regions. These issues highlight the importance of comprehensive disease surveillance and public health strategies in mitigating these long-term epidemiological impacts.

Background: Household transmission of respiratory viruses may drive community spread. Few recent studies have examined household respiratory syncytial virus (RSV) transmission in the United States.

Methods: We conducted a prospective community-based cohort study from 1 June 2022 to 31 May 2023. Participants had blood samples collected and completed nasal swabs and surveys at least weekly, irrespective of symptoms. We tested serum for RSV antibody, nasal swabs by quantitative reverse transcription polymerase chain reaction (RT-qPCR), and performed whole genome sequencing. We evaluated secondary RSV transmission and associated risk factors based on a log-linear Poisson regression model.

Results: RSV was detected among 310 (10%) participants within 200 (20%) households. Most (94%) index cases were symptomatic. We identified 37 cases of potential secondary transmission within 14 days of a distinct index case (10%, 95% confidence interval [CI]: 7%, 14%); median age of index and secondary cases were 6 (interquartile range [IQR]: 3-10) and 35 (7-41) years, respectively, with 89% (24/27) of index cases aged 6 months to 12 years. Factors associated with increased risk of RSV transmission included index case viral detection ≥1 week and contact age ≤12 years. Of 120 sequenced specimens, the main lineages represented were A.d.5.2 (n = 37) and A.d.1 (n = 30). Sequenced viruses from households with ≥2 RSV infections were similar when occurring within ≤14 days (mean pairwise difference 4 [range 0-13], n = 17 households), compared to those >14 days (137 [37-236], n = 2).

Conclusions: Most RSV household transmission occurs from infants and young children to adults. Viral genome sequencing demonstrated that multiple household infections within a 14-day period are likely due to within-household transmission.

Background: Native vertebral osteomyelitis (NVO) is a life-threatening spinal infection with rising incidence and significant morbidity. Despite its growing burden, long-term data on clinical characteristics, management trends, and outcomes remain limited.

Methods: We conducted a 26-year multicenter retrospective cohort study of adults (≥18 years) diagnosed with NVO at Mayo Clinic sites between 1999-2024. Demographic, microbiologic, treatment, and outcome data were analyzed across five time periods. Predictors of treatment failure were assessed using a multivariable competing risk model.

Results: Among 1,255 patients (median age 67; 66% male), lumbosacral involvement was most common (65%), and 21% had multilevel involvement. Pathogens were identified in 77%, most commonly S. aureus (49%; MSSA 37%, MRSA 13%). Over time from 1999-2004 to 2020-2024, Gram-negative bacilli increased from 6% to 14% (p=0.048).Comorbidities including chronic kidney disease (10% to 21%), active chemotherapy (6% to 11%), and immunosuppression (8% to 17%) increased significantly. Additionally, 1-year treatment failure declined (16% to 10%). In multivariable analysis, diabetes mellitus (sHR 1.92, 95% CI 1.18-3.13) and multilevel involvement (sHR 1.67, 95% CI 1.17-2.38) were associated with increased incidence of treatment failure, while concurrent infections (sHR 0.57, 95% CI 0.37-0.87) and higher Charlson Comorbidity Index (CCI) (sHR 0.62, 95% CI 0.43-0.90) were associated with lower failure.

Conclusion: This large multicenter cohort highlights increasing host complexity, shifting microbiology, and predictors of failure, emphasizing the importance of early risk stratification and tailored strategies, such as multidisciplinary evaluation and close follow-up of high-risk patients to improve outcomes.