Prescriptions for Viral Infections Threaten Effectiveness of Antibiotics

A vast majority of people who see their doctors for sore throats or acute bronchitis receive antibiotics, yet only a small percentage should, according to analyses of two major national surveys being presented at IDWeek 2013. Those illnesses usually are caused by viruses, and antibiotics which only treat bacterial infections do not help.

Harvard University researchers analyzed the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey and determined that doctors prescribed antibiotics in 60 percent of visits for sore throats and 73 percent of visits for acute bronchitis. The antibiotic prescribing rate should be about 10 percent for sore throats and nearly zero for acute bronchitis.

The sore throat analysis is being published in JAMA Internal Medicine, available online today.

While antibiotic stewardship programs have helped reduce the misuse of the the medications in hospitals, the analyses suggest the message isnt reaching the community, with patients continuing to request antibiotics for conditions they dont cure, and doctors prescribing them. The inappropriate use of antibiotics adds to the creation of drug-resistant bacteria, or superbugs, which are very difficult to treat and are a public health threat.

Also, people need to understand that by taking antibiotics for viral infections, theyre putting something in their bodies that they dont need, says Jeffrey A. Linder, MD, MPH, associate professor of medicine at Harvard Medical School, associate physician at Brigham & Womens Hospital, Boston, and senior author of the study. Taking antibiotics unnecessarily exposes people to adverse drug reactions, allergies, yeast infections and nausea, with no benefit.

Sore throats caused by streptococcus bacteria (strep) should be treated with antibiotics. But while people often think they have strep throat, streptococcus is the cause only about 10 percent of the time. In most cases, a virus causes the sore throat. Acute bronchitis is almost always viral, and even when bacteria are involved, there is no need for antibiotics unless the patient develops pneumonia, says Linder.

To assess the antibiotic prescribing rate for sore throat, researchers determined there were 94 million visits to primary care physicians and emergency rooms for sore throats between 1997 and 2010, based on an extrapolation of 8,191 visits. Physicians prescribed antibiotics 60 percent of the time, a decrease from 73 percent from numbers reported by the same authors in 2001.

Regarding acute bronchitis, researchers calculated there were 39 million visits to primary care physicians and emergency rooms between 1996 and 2010, based on a extrapolation of 3,667 actual visits. Researchers determined there was a significant increase in the number of visits for acute bronchitis to primary care doctors, from 1.1 million in 1996 to 3.4 million in 2010. They also noted an increase in the antibiotic prescribing rate in emergency rooms, from 69 percent to 73 percent, during the same 14-year period.

Most sore throats and cases of acute bronchitis should be treated with rest, fluids and using a humidifer, and dont require a visit to the doctor, said Dr. Linder. A cough, runny nose and hoarseness usually are signs that a sore throat is viral, not caused by strep. Pain relievers can help. Essentially a chest cold, acute bronchitis involves swelling and inflammation of the bronchial tubes in the lungs and typically follows a head cold or flu, which are viral infections. The illness lasts a week or two, but the cough, caused by lung irritation, may linger for weeks.

Michael Barnett, MD is the first author of the study being presented at IDWeek by Linder. The study was funded by the Agency for Healthcare Research and Quality (AHRQ).

IDWeek 2013 is an annual meeting of the Infectious Diseases Society of America (IDSA), the Society for Healthcare Epidemiology of America (SHEA), the HIV Medicine Association (HIVMA) and the Pediatric Infectious Diseases Society (PIDS). With the theme Advancing Science, Improving Care, IDWeek features the latest science and bench-to-bedside approaches in prevention, diagnosis, treatment, and epidemiology of
infectious diseases, including HIV, across the lifespan. IDWeek 2013 takes place October 2-6 at the Moscone Center in San Francisco. For more information, visit
www.idweek.org/.