New Tool Distinguishes Between Viral, Bacterial Infections

Antibiotics are lifesaving drugs, but overuse is leading to one of the world’s most pressing health threats: antibiotic resistance.

Researchers at the University of Rochester Medical Center are developing a tool to help physicians prescribe antibiotics to patients who really need them, and avoid giving them to individuals who do not, Medical Xpress reported.

Antibiotics help us fight bacterial infections, but are not effective and should not be used to treat viruses.

Scientists from the university’s National Institute of Health-funded Respiratory Pathogens Research Center identified 11 genetic markers in blood that accurately distinguished between viral and bacterial infections.

The finding, published today in the journal Scientific Reports, is important because physicians do not have a good way to confirm bacterial infections like pneumonia and more-often-than-not default to an antibiotic.

“It’s extremely difficult to interpret what’s causing a respiratory tract infection, especially in very ill patients who come to the hospital with a high fever, cough, shortness of breath and other concerning symptoms,” said Ann R. Falsey, M.D., lead study author, professor and interim chief of the Infectious Diseases Division at UR Medicine’s Strong Memorial Hospital.

“My goal is to develop a tool that physicians can use to rule out a bacterial infection with enough certainty that they are comfortable, and their patients are comfortable, foregoing an antibiotic.”

Falsey’s project caught the attention of the federal government; she is one of 10 semifinalists in the Antimicrobial Resistance Diagnostic Challenge, a competition sponsored by NIH and the Biomedical Advanced Research and Development Authority to help combat the development and spread of drug resistant bacteria.

Selected from among 74 submissions, Falsey received $50,000 to continue her research and develop a prototype diagnostic test, such as a blood test, using the genetic markers her team identified.

A group of 94 adults hospitalized with lower respiratory tract infections were recruited to participate in Falsey’s study. The team gathered clinical data, took blood from each patient, and conducted a battery of microbiologic tests to determine which individuals had a bacterial infection (41 patients) and which had a non-bacterial or viral infection (53 patients).

Thomas J. Mariani, Ph.D., professor of Pediatrics and Biomedical Genetics at URMC, used complex genetic and statistical analysis to pinpoint markers in the blood that correctly classified the patients with bacterial infections 80 to 90% of the time.