Rapid Antigen-Based Assay Detects Tick-Borne Diseases Before Symptoms Appear
By LabMedica International staff writers Posted on 04 Feb 2025 |

Tick-borne spotted fever rickettsioses (SFRs) continue to pose a significant threat to otherwise healthy individuals, causing severe illness and death due to the lack of a reliable and timely diagnostic laboratory test. The absence of specific, convenient, acute-phase diagnostic tests for SFRs contributes to their difficulty in diagnosis and underreporting. Currently, the gold standard for diagnosing tick-borne rickettsioses involves detecting antibodies against rickettsiae in the serum through indirect immunofluorescence assay (IFA). However, this antibody response typically appears 7 to 10 days after illness onset, when fatalities often occur. While molecular detection of bacterial DNA and immunohistochemical analysis of rickettsial antigens in skin biopsies may provide early diagnosis, the occurrence of skin rashes and their timing are unreliable. Furthermore, many hospital laboratories do not perform rapid molecular diagnostic testing for SFRs. Researchers have now identified a biomarker for SFRs, leading to the development of a prototype laboratory test aimed at detecting this biomarker for more accurate diagnosis.
Researchers at University of Houston (Houston, TX, USA) have identified a rickettsial protein, RC0497, in R. conorii-infected endothelial cell supernatant. RC0497, a putative N-acetylmuramoyl-L-alanine amidase, is highly conserved across various SFG species. The researchers showed that RC0497 is present in the blood of both infected mouse models of Mediterranean spotted fever (MSF) and MSF patients. In this study, the researchers tested the hypothesis that detecting RC0497 through a rapid lateral flow assay (LFA) could provide a timely diagnostic tool, potentially improving treatment outcomes for severe SFRs. The team used two experimental models of SFRs—R. conorii-infected C3H/HeN mice and R. rickettsii-infected guinea pigs—which replicate the pathophysiological changes seen in patients with Rocky Mountain spotted fever (RMSF). They measured RC0497 concentrations at various disease stages by mass spectrometry (MS) using blood samples from infected animals.
Using specific antibodies against RC0497 and europium chelate nanoparticle reporters, the researchers developed a europium nanoparticle LFA (EuNP LFA) to detect this biomarker for SFRs. The assay demonstrated high analytical sensitivity and specificity in serum samples from experimentally infected animals at the early stages of infection, when antibiotics could still control rickettsiae. The results suggest that detecting RC0497 in a timely manner using the europium LFA could guide treatment, significantly improving infection outcomes. This represents the first rapid antigen-detection test prototype based on a lateral flow assay platform for diagnosing life-threatening SFRs in a timely manner.
The research confirmed that a rickettsial antigen, detectable by a simple test, is present in the circulation of infected animals. Unlike serological tests used to detect past exposure to potentially nonpathogenic rickettsial species, the RC0497 LFA can distinguish active infections. This will enhance clinical diagnosis and epidemiological surveillance. Although further validation with patient specimens is needed, the team has established proof-of-concept for an LFA that could potentially be developed into a point-of-care diagnostic tool for use in real-world settings.
Latest Molecular Diagnostics News
- Innovative Bio-Detection Platform Improves Early Cancer Screening and Monitoring
- Blood Test Could Help More Women Survive Aggressive Triple Negative Breast Cancer
- CSF Test Distinguishes Prion Disease from Other Causes of Rapidly Progressive Dementia
- Newly Identified Stroke Biomarkers Pave Way for Blood Tests to Quickly Diagnose Brain Injuries
- CRISPR-Based Test Diagnoses Life-Threatening Fungal Infection More Quickly
- First Of Its Kind Measles Antibody Test Validated for Use with Dried Blood Spot Samples
- Simple Blood Test to Advance Targeted Treatments for Childhood Cancer
- Blood Test to Measure Organ Ageing Could Predict Disease Risk Decades in Advance
- New Test Detects Parasite Responsible for Trichomoniasis Infection In 15 Minutes
- Blood Test to Improve Diagnosis and Management of ALS
- New Technique to Measure Circulating Tumor DNA May Improve Metastatic Cancer Surveillance
- Blood Test Trial Could Unlock New Dementia Treatments
- New Test Measures Biological Age Using Saliva or Blood
- Blood Test Could Identify Expectant Mothers at Risk of Preterm Delivery
- Umbilical Cord Blood Test Could Identify Preterm Infants at Risk for Medical Complications
- Breakthrough Technology Represents Leap Forward in Next-Generation Sequencing
Channels
Clinical Chemistry
view channel
Paper-Based Device Boosts HIV Test Accuracy from Dried Blood Samples
In regions where access to clinics for routine blood tests presents financial and logistical obstacles, HIV patients are increasingly able to collect and send a drop of blood using paper-based devices... Read more
AI-Powered Raman Spectroscopy Method Enables Rapid Drug Detection in Blood
Accurately monitoring drug levels in the blood is essential for effective treatment, particularly in the management of cardiovascular diseases. Traditional techniques for monitoring blood drug levels often... Read more
Novel LC-MS/MS Assay Detects Low Creatinine in Sweat and Saliva
Timely and accurate monitoring of renal function is essential for managing patients at risk of acute kidney injury (AKI), which affects about 12% of hospitalized patients and up to 57% of ICU patients.... Read more
Biosensing Technology Breakthrough Paves Way for New Methods of Early Disease Detection
Nanopores are tiny openings that can detect individual molecules as they pass through, making them ideal for analyzing biomolecules like DNA and proteins. However, detecting proteins at extremely low ... Read moreHematology
view channel
Non-Invasive Prenatal Test for Fetal RhD Status Demonstrates 100% Accuracy
In the United States, approximately 15% of pregnant individuals are RhD-negative. However, in about 40% of these cases, the fetus is also RhD-negative, making the administration of RhoGAM unnecessary.... Read more
WBC Count Could Predict Severity of COVID-19 Symptoms
The global health crisis caused by the SARS-CoV-2 virus continues to impact millions of people worldwide, with many experiencing persistent symptoms months after the initial diagnosis. Cognitive impairment... Read more
New Platelet Counting Technology to Help Labs Prevent Diagnosis Errors
Accurate platelet count testing is a significant challenge for laboratories. Inaccurate results can lead to misdiagnosis, missed diagnoses, and delayed treatment for a variety of potentially fatal conditions,... Read more
Streamlined Approach to Testing for Heparin-Induced Thrombocytopenia Improves Diagnostic Accuracy
Heparin-induced thrombocytopenia (HIT), a serious side effect of the blood thinner heparin, is difficult to diagnose because thrombocytopenia, or low platelet count, can be caused by a variety of factors... Read moreImmunology
view channelCerebrospinal Fluid Test Predicts Dangerous Side Effect of Cancer Treatment
In recent years, cancer immunotherapy has emerged as a promising approach where the patient's immune system is harnessed to fight cancer. One form of immunotherapy, called CAR-T-cell therapy, involves... Read more
New Test Measures Preterm Infant Immunity Using Only Two Drops of Blood
Preterm infants are particularly vulnerable due to their organs still undergoing development, which can lead to difficulties in breathing, eating, and regulating body temperature. This is especially true... Read more
Simple Blood Test Could Help Choose Better Treatments for Patients with Recurrent Endometrial Cancer
Endometrial cancer, which develops in the lining of the uterus, is the most prevalent gynecologic cancer in the United States, affecting over 66,000 women annually. Projections indicate that in 2025, around... Read moreMicrobiology
view channel
Gastrointestinal Panel Delivers Rapid Detection of Five Common Bacterial Pathogens for Outpatient Use
Acute infectious gastroenteritis results in approximately 179 million cases each year in the United States, leading to a significant number of outpatient visits and hospitalizations. To address this, a... Read more
Rapid PCR Testing in ICU Improves Antibiotic Stewardship
A collaborative study led by the University of Plymouth (Devon, UK) has shown that rapid polymerase chain reaction (PCR) testing in the intensive care unit (ICU) improved antibiotic stewardship compared... Read morePathology
view channel
Informatics Solution Elevates Laboratory Efficiency and Patient Care
QuidelOrtho Corporation (San Diego, CA, USA) has introduced the QuidelOrtho Results Manager System, a cutting-edge informatics solution designed to meet the increasing demands of modern laboratories.... Read more
Microfluidic Device Assesses Stickiness of Tumor Cells to Predict Cancer Spread
Ductal carcinoma in situ (DCIS), a type of early-stage breast cancer, is often referred to as stage zero breast cancer. In many cases, it remains harmless and does not spread beyond the milk ducts where... Read more
New AI Tool Outperforms Previous Methods for Identifying Colorectal Cancer from Tissue Sample Analysis
Tissue analysis typically involves a pathologist reviewing scanned digital slides from a patient’s intestinal sample and marking specific areas, such as those where cancerous and related tissues are present.... Read moreTechnology
view channel
POC Paper-Based Sensor Platform to Transform Cardiac Diagnostics
Cardiovascular diseases continue to be the leading cause of death worldwide, accounting for over 19 million fatalities annually. Early detection of myocardial infarction (MI), commonly known as a heart... Read more
Study Explores Impact of POC Testing on Future of Diagnostics
In today’s rapidly changing world, having quick and accurate access to medical information is more crucial than ever. Point-of-Care Diagnostics (PoC-D) and Point-of-Care Testing (PoC-T) are making this... Read more
Low-Cost, Fast Response Sensor Enables Early and Accurate Detection of Lung Cancer
Cancer biomarkers are valuable tools for early diagnosis as their concentration in body fluids, such as serum, can be measured to detect the disease at an earlier stage. Additionally, serum levels of these... Read moreIndustry
view channel
CACLP 2025 Unites Global Innovators in IVD Industry
CACLP (Shanghai, China) will be holding the 22nd China International In Vitro Diagnostic Expo, the largest and most influential gathering of the IVD industry in China, 22-24 March 2025 at the Hangzhou... Read more
Bio-Rad to Acquire Digital PCR Developer Stilla Technologies
Bio-Rad Laboratories (Hercules, CA, USA) has entered into a binding offer to purchase all equity interests in Stilla Technologies (Villejuif, France). The acquisition remains subject to consultation with... Read more