Open Forum Infectious Diseases最新文献

[This corrects the article DOI: 10.1093/ofid/ofaf734.].

Bloodstream infection in patients with cardiovascular implantable electronic devices (CIEDs) is not uncommon. Among veterans with CIEDs from 2018 to 2023, 4.7% (1893 of 40 243) developed bacteremia. CIED involvement was identified in 305 patients. Factors associated with increased risk of CIED involvement included known infection of other devices and a diagnosis of endocarditis; urinary tract infection was associated with decreased risk.

We assessed baseline C-reactive protein (CRP) and procalcitonin levels in asymptomatic individuals from malaria-endemic West Africa. C-reactive protein remained unaffected by Plasmodium falciparum parasitemia, while procalcitonin (PCT) was more frequently detectable among malaria-positive individuals. These findings support that CRP thresholds remain valid and highlight the need to explore parasite density-PCT associations.

[This corrects the article DOI: 10.1093/ofid/ofag025.].

Background: Taiwan, a region traditionally considered non-endemic for dengue, experienced an unexpected and large-scale outbreak in 2023. We investigated the multifactorial drivers of this outbreak, including cross-border viral importation, serotype cocirculation, vector ecology, and climate variability.

Methods: We analyzed national dengue surveillance data (2013-2023), meteorological records, and Breteau Index (BI) values, alongside molecular serotyping and whole-genome sequencing of clinical isolates. Time-lagged Poisson regression was used to identify predictors of indigenous dengue transmission in Kaohsiung and Tainan. Full-genome comparisons were conducted between 2023 strains and historical epidemic isolates.

Results: A total of 26 706 laboratory-confirmed cases were reported, primarily in Tainan (80.7%) and Kaohsiung (11.9%). Real-time RT-PCR identified cocirculating DENV-1 and DENV-2 strains. Phylogenetic analysis confirmed the 2023 DENV-1 and DENV-2 strains were genetically linked to contemporary strains from Southeast Asian countries. Whole-genome sequencing identified several nonsynonymous mutations in the NS2A, NS3, and NS5 regions when compared with historical outbreak isolates. Time-lagged regression showed that imported cases, precipitation, and the BI were associated with incidence in univariate models. In Kaohsiung, the best-fitting multivariable model included the BI, but temperature and precipitation were the independent predictors. In Tainan, precipitation and, at longer lags, imported cases were more influential, while the BI lost significance after adjustment.

Conclusions: The 2023 dengue outbreak in Taiwan was driven by a complex interplay between viral introductions, climatic conditions, and vector dynamics. The differing transmission drivers observed between cities highlight the need for region-specific vector surveillance, climate-informed early warning systems, and sustained genomic monitoring to prevent future re-emergence of dengue in this non-endemic setting.

Background: Our previous study suggested that mixed infection with R5 and X4/dual human immunodeficiency virus type 1 (HIV-1) may contribute to coreceptor switch from R5 to X4 HIV-1. To confirm this hypothesis, we investigated mixed HIV-1 infections in people who inject drugs (PWID) infected with the CRF01_AE subtype.

Methods: Viral plasma RNA from PWID were extracted, the V3 region of the HIV-1 gp120 gene was amplified, and deep sequencing was performed. Coreceptor usage was determined using phenotypic assay by cloning each V3 region. Coreceptor usage of minor HIV-1 variants detected by deep sequencing was predicted based on the amino acid sequences of the V3 region.

Results: Deep sequencing of plasma from 36 PWID revealed that mixed HIV-1 infection involving different coreceptor usage occurred in 13 cases (36.1%). Phylogenetic analysis revealed that R5 variants were dominant, whereas X4/dual variants were detected as minor populations in most cases. In 1 case, however, R5 variants emerged as a distinct minor population mixed with X4/dual variants as the major population. Notably, plasma viral RNA load (pVL) was higher in cases of mixed infection with R5 and X4/dual HIV-1 than in those infected solely with R5 HIV-1.

Conclusions: Our observations suggest a possible association between mixed HIV-1 coreceptor usage and coreceptor switch in CRF01_AE-infected PWID, and that mixed infection may be associated with pVL.

Background: Most studies of human metapneumovirus (HMPV) epidemiology have been among inpatients. This study examined the epidemiology of HMPV compared with other common viruses among outpatients seeking care for an acute respiratory illness (ARI) during 5 influenza seasons (2016-2017 to 2019-2020, before the coronavirus disease 2019 pandemic, and in 2021-2022, during the pandemic).

Methods: Outpatients ≥6 months old seeking care for ARI and presenting with cough of ≤7 days' duration provided nasal and pharyngeal swab samples, demographic data, and access to electronic medical record data. Samples were tested with reverse-transcription polymerase chain reaction assays for HMPV, influenza, parainfluenza virus (PIV) 1-4, respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Student's t and χ² tests were used to compare HMPV cases with other ARIs.

Results: After exclusion of 68 coinfections, 7143 patients remained; 2017 had influenza, 762 had RSV, 423 had HMPV, 83 had PIV, 352 had SARS-CoV-2, and 3506 tested polymerase chain reaction negative for all of these viruses. Of all patients with ARI each influenza season, 30.2%-37.1% tested positive for influenza, 11.3%-13.6% for RSV, 4.7%-7.3% for HMPV, and 0.1%-1.9% for PIV. Compared with patients with RSV, those with HMPV less often had congestion, dyspnea, and sore throat. Compared with patients with influenza, those with HMPV were less likely to have fever but more often had congestion or dyspnea and felt worse at 7-14-day follow-up. Children recovered from HMPV faster than adults.

Conclusions: HMPV is an important cause of outpatient ARI during influenza season. Patients with HMPV had slightly different demographic characteristics and symptoms from those with other ARIs.

Background: The clinical and microbiological features of infection due to non-tuberculous mycobacteria (NTM) after hematopoietic stem-cell transplantation (HSCT) remain poorly understood.

Methods: We performed a retrospective, multinational case-control study that included HSCT recipients (≥12 years) diagnosed with NTM disease between January 2008 and December 2018. Controls were HSCT recipients with no evidence of NTM disease, matched (1:2 ratio) by participating center and post-transplant survival. Logistic regression on matched pairs was used to investigate risk factors for NTM disease.

Results: We included 25 cases of NTM disease. The most common HSCT type was allogeneic from unrelated donor (72.0%) after myeloablative conditioning (76.0%). Predominant hematological conditions were acute myelogenous leukemia (28.0%) and myelodysplastic syndrome (24.0%). Most patients (88.0%) had previously received immunosuppressive therapy. The most common species identified were Mycobacterium avium complex (64.0%) and rapidly growing mycobacteria (20.0%). Most patients (68.0%) had pulmonary disease. All but one received antimycobacterial therapy for a median of 267.5 days. Macrolides (83.3%), rifamycins (58.3%) and ethambutol (62.5%) were the most commonly used drugs. Four patients (16.7%) developed adverse events requiring therapy discontinuation. All-cause and attributable mortality rates were 28.0% and 4.0%, respectively. One patient experienced relapse after 464 days. Diagnosis of a non-NTM infection (adjusted odds ratio [aOR]: 3.11; 95% confidence interval [95% CI]: 1.25-7.78) and corticosteroid therapy (aOR: 2.88; 95% CI: 1.16-7.17), both within the previous 90 days, were associated with NTM disease.

Conclusions: NTM disease is a serious complication among heavily immunocompromised HSCT recipients associated with prior non-NTM infection and corticosteroid therapy.

Background: Tuberculosis (TB) recurrence remains a significant public health concern, even in regions with low incidence. Recurrent TB may result from endogenous reactivation of a previous infection or from exogenous reinfection with a new strain. Distinguishing between these mechanisms is crucial for understanding TB dynamics and optimizing control strategies. This study aims to determine the frequency of TB recurrence in Aragón, Spain, a region with low TB incidence, and to identify factors associated with reactivation and reinfection over a 30-year period.

Methods: A retrospective, descriptive study including all genotyped Mycobacterium tuberculosis isolates from 1993 to 2022 was conducted in Aragón. IS6110-RFLP was the method used to genotype strains. Recurrences were classified as reactivation or reinfection based on molecular profiles. Clinical and epidemiological data were retrieved from medical records. Appropriate statistical tests were applied to compare groups.

Results: Among 3510 genotyped TB cases, 81 (2.30%) were recurrent: 68 reactivations (1.93%) and 15 reinfections (0.42%). Reinfection was significantly associated with change of residence, HIV infection, cancer diagnosis in the second episode, and multimorbidity. Time to recurrence was significantly longer in reinfections (median 7.0 years) compared to reactivations (2.0 years). Most isolates belonged to Lineage 4 , and reinfection strains were more often linked to clustered strains circulating in the community.

Conclusions: In this low-incidence setting, TB recurrence is rare and mainly the result of reactivation. Reinfections, though less frequent, are linked to mobility, HIV co-infection, neoplasm, and compromised health status. These findings underscore the importance of long-term molecular surveillance and targeted follow-up for high-risk patients.

Background: SARS-CoV-2 is a major cause of outpatient-attended acute respiratory infections (ARIs). Data from Africa are limited on SARS-CoV-2 infection, variants, symptom profile, and longitudinal trends for outpatient presentation.

Methods: Starting December 2020, we established ARI surveillance at 5 outpatient clinics in coastal Kenya, recruiting ∼15 participants (any age) per week per clinic for SARS-CoV-2 testing and genome analysis. Participants provided respiratory samples, demographic details, and vaccination and symptom data. We compared SARS-CoV-2 clinical and molecular epidemiology before and during Omicron waves using multivariate logistic regression.

Results: By February 2025, we had recruited 14 562 ARI cases, with 1053 (7.2%) testing positive for SARS-CoV-2. The median age of cases was 25 years (IQR, 15-41) and 65.0% were female. Nine infection waves were recorded, with positivity ranging 8.2% to 25.6%. Interwave intervals increased from ≤3 months in 2021 to ≥6 months in 2024. Sixty-eight PANGO lineages were identified from 782 (74.2%) sequenced cases, with 4 predominating local waves (AY.116, BQ.1.8, FY.4.1, LF.7.3.2), which were rare globally (<0.5%) during their detection period. Overall, common symptoms among positive cases were cough (91.5%), nasal discharge (76.7%), and fever (53.1%). Loss of sense of smell was strongly predictive of COVID-19 in the pre-Omicron era, but body malaise, sore throat, joint pain, and nasal discharge were predictive during the Omicron period.

Conclusions: SARS-CoV-2 increasingly shows seasonal annual patterns in coastal Kenya, with its clinical features resembling established endemic respiratory viruses. Its case burden is most pronounced in young adults. Locally dominant genetic variants may differ from those globally.