FebriDx testing to tell viral from bacterial infections in children

FebriDx® Pediatric Validation Study Protocol

Observational Lumos Diagnostics · NCT07211997

This study will test whether the FebriDx fingerstick test can tell bacterial from non-bacterial causes of fever in children ages 2–11 who come to emergency, urgent care, or primary care with respiratory symptoms.

Quick facts

Study typeObservational
Enrollment800 (estimated)
Ages2 Years to 11 Years
SexAll
SponsorLumos Diagnostics Industry-sponsored
Drugs / interventionsChemotherapy, Methotrexate
Locations10 sites (Colton, California and 9 other locations)
Trial IDNCT07211997 on ClinicalTrials.gov

What this trial studies

This is a prospective, multi-center, observational, blinded study enrolling febrile children aged 2–11 with suspected acute respiratory infections. Participants will receive a FebriDx point-of-care fingerstick test that detects MxA and CRP levels, and results will be compared to a clinical adjudication reference that includes pathogen detection (culture, PCR) and host-response measures. The primary outcome is whether a bacterial-associated systemic host immune response is present, as determined by the adjudication panel using a Clinical Reference Algorithm. Data will be collected at community EDs, urgent care centers, and primary care offices at multiple U.S. sites.

Who should consider this trial

Good fit: Children aged 2–11 with a measured or reported fever ≥100.4°F (≥38°C) within 72 hours and new onset respiratory symptoms who present to a participating ED, urgent care, or primary care clinic and whose parent/guardian can provide consent (and assent when appropriate).

Not a fit: Children who are immunocompromised, have taken antibiotics or antivirals in the prior 14 days, received a live vaccine in the prior 14 days, are outside the 2–11 age range, or cannot complete follow-up are unlikely to benefit from this validation effort.

Why it matters

Potential benefit: If successful, this test could help clinicians quickly identify likely bacterial infections in children, reducing unnecessary antibiotics and enabling faster appropriate care.

How similar studies have performed: Similar FebriDx and MxA/CRP point-of-care approaches have shown promising accuracy in adults and small pediatric cohorts, but comprehensive pediatric validation is still limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Signed informed consent by parent/guardian and Assent for ages 7-11 years
* Exhibit or report of a new onset measured temperature (oral or tympanic) of greater than or equal to 100.4°F/38°C within 3 days (72 hours) of enrollment
* Clinical suspicion for Acute Respiratory Infection beginning within 7 days before enrollment AND presents with at least one of the following new onset of symptoms: runny nose, nasal congestion, sore throat, cough, hoarse voice, shortness of breath / difficulty breathing

Exclusion Criteria:

* Unwilling to participate in 7-day follow-up or sign HIPAA waiver to obtain medical record if hospitalized
* Immunocompromised state or taking immunosuppressive or chemotherapeutic medications in the last 30 days (e.g. oral / inhaled steroids, Methotrexate, Cyclosporine, Chemotherapy, interferon therapy)
* Taking antibiotics or antiviral therapy in the last 14 days
* Received a live viral immunization in the last 14 days
* Clinical diagnosis of otitis media or recognizable viral syndrome (i.e., croup, varicella, stomatitis) at the time of enrollment
* Prior enrollment in the study

Where this trial is running

Colton, California and 9 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Acute Respiratory InfectionsPediatricHost immune responseBiomarkersPoint-of-CareMyxovirus resistance protein AC-reactive protein
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.