Background: Pandemic influenza A(H1N1)pdm09 emerged in Thailand in 2009. A prospective longitudinal adult cohort and household transmission study of influenza-like illness (ILI) was ongoing in rural Thailand at the time of emergence. Symptomatic and subclinical A(H1N1)pdm09 infection rates in the cohort and among household members were evaluated.
Methods: A cohort of 800 Thai adults underwent active community-based surveillance for ILI from 2008-2010. Acute respiratory samples from ILI episodes were tested for A(H1N1)pdm09 by qRT-PCR; acute and 60-day convalescent blood samples were tested by A(H1N1)pdm09 hemagglutination inhibition assay (HI). Enrollment, 12-month and 24-month follow-up blood samples were tested for A(H1N1)pdm09 seroconversion by HI. Household members of influenza A-infected cohort subjects with ILI were enrolled in household transmission investigations in which day 0 and 60 blood samples and acute respiratory samples were tested by either qRT-PCR or HI for A(H1N1)pdm09. Seroconversion between annual blood samples without A(H1N1)pdm09-positive ILI was considered as subclinical infection.
Results: The 2-yr cumulative incidence of A(H1N1)pdm09 infection in the cohort in 2009/2010 was 10.8% (84/781) with an annual incidence of 1.2% in 2009 and 9.7% in 2010; 83.3% of infections were subclinical (50% in 2009 and 85.9% in 2010). The 2-yr cumulative incidence was lowest (5%) in adults born ≤ 1957. The A(H1N1)pdm09 secondary attack rate among household contacts was 47.2% (17/36); 47.1% of these infections were subclinical. The highest A(H1N1)pdm09 secondary attack rate among household contacts (70.6%, 12/17) occurred among children born between 1990 and 2003.
Conclusion: Subclinical A(H1N1)pdm09 infections in Thai adults occurred frequently and accounted for a greater proportion of all A(H1N1)pdm09 infections than previously estimated. The role of subclinical infections in A(H1N1)pdm09 transmission has important implications in formulating strategies to predict and prevent the spread of A(H1N1)pdm09 and other influenza virus strains.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4154756 | PMC |
| http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0106751 | PLOS |
Publication Analysis
Top Keywords
Similar Publications
Expression and clinical significance of miR-421 in prostate cancer.
Biomarkers
January 2025
Department of Pathology, Anhui Medical University, Hefei, Anhui, China.
Objective: To examine the role and diagnostic potential of miR-421 in prostate cancer (PCa).
Methods: Expression data and clinical information for miR-421 were obtained from the TCGA and Genotype-Tissue Expression (GTEx) databases. Experimental validation was performed at the cellular, blood, and tissue levels to confirm miR-421 expression and its association with clinicopathological features.
Characterization of the immune cell profile in metastatic nasopharyngeal carcinoma treated with chemotherapy and immune checkpoint inhibitors.
Am J Cancer Res
December 2024
Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Chang Gung University Taoyuan 33305, Taiwan.
Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV)-associated cancer, and immune checkpoint inhibitors (ICIs) have shown efficacy in its treatment. The combination of chemotherapy and ICIs represents a new trend in the standard care for metastatic NPC. In this study, we aim to clarify the immune cell profile and related prognostic factors in the ICI-based treatment of metastatic NPC.
View Article and Find Full Text PDFInteraction of breast cancer-relevant DNA repair genes and air pollution in relation to breast cancer risk in UK biobank.
Am J Cancer Res
December 2024
Department of Epidemiology, University of Florida, College of Public Health and Health Professions and College of Medicine Gainesville, FL, USA.
We investigated if selected polymorphisms in DNA repair genes modify the association between exposure to particulate matter ≤ 10 micron in diameter (PM) and breast cancer (BCa) risk. We included 150,929 postmenopausal women (5,969 with BCa) from UK Biobank, a population-based prospective cohort. Cancer diagnoses were ascertained through the linkage to the UK National Health Service Central Registers.
View Article and Find Full Text PDFImpact of body mass index on in-hospital outcomes in patients receiving leadless pacemakers: A five-category analysis.
Heart Rhythm O2
December 2024
Department of Internal Medicine, Burnett School of Medicine at Texas Christian University (TCU) and Consultants in Cardiovascular Medicine and Science, Fort Worth, Texas.
Background: The adoption of leadless pacemakers (LPMs) is increasing, yet the impact of body mass index (BMI) on procedural outcomes remains underexplored.
Objective: The purpose of this study was to explore the impact of BMI on in-hospital outcomes for patients receiving LPM implantation.
Methods: Data from the National Inpatient Sample from 2018-2021 were analyzed for patients older than 18 years who underwent LPM implantation, with specific inclusion and exclusion criteria applied.
Ventricular tachycardia ablation across age groups: Outcomes, trends and demographics. Insights from the National Inpatient Sample Database.
Heart Rhythm O2
December 2024
Department of Cardiology, Geisinger Medical Center, Danville, Pennsylvania.
Background: Ventricular tachycardia ablation (VTA) is an important treatment option for ventricular tachycardia, with increasing use across all age groups. However, age-related differences in outcomes remain a concern.
Objective: This study aimed to investigate age-related trends in VTA procedures and their associated adverse events across the United States from 2011 to 2021.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!