Heads or Tails: Many illnesses have the same symptoms; diagnostic tools can beat the guessing game.

Courtesy Photo | Many illnesses have the same symptoms; diagnostic tools can beat the guessing game.  

FORT BELVOIR , VA, UNITED STATES

10.06.2020

Courtesy Story

Defense Threat Reduction Agency's Chemical and Biological Technologies Department

“I woke up with a cough and a sore throat. What should I do? Should I go to work? Should I see a doctor?” Without answers, these questions promote uncertainty, stress, and the potential for the symptoms to become worse, and during the COVID-19 pandemic, the answers are even more necessary as close to symptom onset as possible. If the cause of the illness is bacterial, then an antibiotic is necessary; if the cause of the illness is viral, then an antibiotic is inappropriate because taking an antibiotic for a viral infection can lead to antibiotic resistance. Each year in the United States, about three million Americans fall ill to antibiotic-resistant infections, and 35,000 die from those illnesses.¹ To definitively answer whether an infection is bacterial versus viral, the Defense Threat Reduction Agency’s (DTRA) Chemical and Biological Technologies Department — in its role as the Joint Science and Technology Office (JSTO) for the Chemical and Biological Defense Program — supported an international company to develop a new screening device that quickly informs clinicians whether a person has a bacterial or viral infection.

DTRA-JSTO’s effort to develop the screening device began in 2017, and clinical trials of the device are occurring in the United States, as reported at the February 2020 meeting of the Presidential Advisory Council on Combatting Antibiotic Resistant Bacteria. Data from the trials may convince the U.S. Food and Drug Administration (FDA) to clear the device for sale in the United States. With FDA approval, warfighters and civilians will be able to visit their local health clinics and learn — in as little as 15 minutes with blood from a finger prick — if their symptoms are due to an active bacterial or viral infection.

The screening device is small, about 7 inches in length, width, and height (see Figure 1). It runs on electricity and needs capillary blood from a finger prick to evaluate a person’s infection status and type. The device analyzes the blood for three proteins associated with an active infection: 1) C-reactive protein, which increases in quantity if the body is fighting an infection; 2) IP-10 protein, which increases in quantity if the infection is bacterial; and 3) the TRAIL protein, which increases in quantity if the infection is viral. After analyzing the blood, the screening device produces a risk score between 0 and 100; a score between 0 and 35 indicates a viral infection, and a score between 65 and 100 indicates a bacterial infection.² A score between 36 and 64 means that the test is equivocal (ambiguous or indeterminate); if symptoms persist, the test can be repeated. The bacterial-versus-viral screening test has a sensitivity rate greater than 90%, which means that it correctly classifies a person as having an infection. The device’s specificity rate is also greater than 90%, which means that it correctly classifies a person as not having an infection.

FDA clearance of the device will mean that an American warfighter and civilian — adult or pediatric — will be able to receive a bacterial-versus-viral infection diagnosis that is quicker and more accurate than through the use of traditional methods of measuring blood pressure and body temperature, and listening to the lungs. Healthy Americans can return to normal activities while unwell Americans receive appropriate health care and have their blood, mucous, or other cultures taken to identify the most effective therapeutic.

DTRA-JSTO is sending the screening device to a U.S. Navy clinical laboratory for early operational assessment and for assessments at allied government clinical laboratories. One day, warfighters may be able to carry a portable version of the device in their personal kit — and DTRA-JSTO would have enabled that future.


^1. Centers for Disease Control and Prevention (CDC). Antibiotic / antimicrobial resistance (AR / AMR): biggest threats and data. CDC website. https://www.cdc.gov/drugresistance/biggest-threats.html. Accessed July 22, 2020.

^2. Srugo I, Klein A, Stein M, et al. 2017. Validation of a Novel Assay to Distinguish Bacterial and Viral Infections. Pediatrics. 140(4):e20163453

POC: Nathan W. Adams, Ph.D., [e-mail]

• Date Taken: 10.06.2020
• Date Posted: 10.06.2020 16:05
• Story ID: 380358
• Location: FORT BELVOIR , VA, US