Instruct: Identify the main category of the given Medrxiv paper based on the title.
Query: Burden of SARS-CoV-2 and protection from symptomatic second infection in children
ANALYSIS OF FOUR DIFFERENT TRANSPORT AND PRESERVATION MEDIUM KITS FOR SARS-COV-2 DIAGNOSIS FROM NASOPHARYNGEAL SWAB BY REAL-TIME PCR: ADAPTING TO THE CONSTANTLY INCREASING DEMAND OF SAMPLING PROCESSING AND STOCK-OUTS DURING THE PANDEMIC
Using genotyping and whole-exome sequencing data to improve genetic risk prediction in deep venous thrombosis
Risk of myocarditis and pericarditis following COVID-19 vaccination in England and Wales
Corneal cisterns as drainage aqueducts
Geographic clusters of objectively measured physical activity and the characteristics of their built environment in a Swiss urban area
Use of repeated mammograms to evaluate risk of breast cancer: a systematic review of methods used in the literature
Deep learning driven quantification of interstitial fibrosis in kidney biopsies
Peripheral Inflammatory Cytokine Signature Mirrors Motor Deficits in Mucolipidosis IV
Changes in the trajectory of Long Covid symptoms following COVID-19 vaccination: community-based cohort study
Declines and pronounced state-level variation in tapentadol use in the US
WHY SOME HESITATE MORE: CROSS-CULTURAL VARIATION IN CONSPIRACY BELIEFS, BELIEF IN SCIENCE, AND VACCINE ATTITUDES
How and why do Quality Circles work for General Practitioners - a realist approach
Tau, β-amyloid, and glucose metabolism following service-related Traumatic Brain Injury in Vietnam war veterans: The AIBL-VETS study
Intrinsic Capacity of Rural Elderly in Thar Desert using WHO ICOPE (Integrated Care for Older Persons) Screening Tool: A Pilot Study
Estimates of the impact on COVID-19 deaths of unequal global allocations of vaccines
Lipid-Modulating Agents for Prevention or Treatment of COVID-19 in Randomized Trials
SARS-CoV-2 Variant of Concern 202012/01 has about twofold replicative advantage and acquires concerning mutations
Synthesizing evidence from the earliest studies to support decision-making: to what extent could the evidence be reliable?
World Science against COVID-19: Gender and Geographical Distribution of Research.
Towards Equitable Patient Subgroup Performance by Gene-Expression-Based Diagnostic Classifiers of Acute Infection
Emergence and Expansion of the SARS-CoV-2 Variant B.1.526 Identified in New York
A Dynamic Bayesian Model for Identifying High-Mortality Risk in Hospitalized COVID-19 Patients
Covid-19 Exposure Assessment Tool (CEAT): Easy-to-use tool to quantify exposure based on airflow, group behavior, and infection prevalence in the community
Development of Novel Measures for Alzheimer's Disease Prevention Trials (NoMAD)
Polygenic risk, lifestyle, and cardiovascular mortality: a prospective population-based UK Biobank study