In a 2017 study, researchers investigated the use of antivirals in children hospitalized for influenza. Rates of prescription of anti-influenza medication in children were found to be below recommended levels and varied significantly between hospitals.
The recommended treatment for children hospitalized due to infection with influenza viruses, especially children with conditions which may increase the risk of influenza-related complications, is the administration of antiviral medications called neuraminidase inhibitors – drugs which prevent the spread of the virus between cells. However, research has indicated that antiviral medications are applied less frequently than necessary. Understanding patterns of antiviral use would allow health professionals to make informed decisions regarding the standards of care, research, and policies involving the treatment of severe influenza.
In a 2017 study published in JAMA Pediatrics, researchers investigated the prescription and use of antiviral medications in children across 46 hospitals in the United States. The records of 35,909 influenza patients under the age of 18 hospitalized during the 2007-2015 flu seasons (October 1 to March 15) and the H1N1 “swine flu” pandemic (April 1 to September 30, 2009) were analyzed with respect to the prescription of the neuraminidase inhibitors oseltamivir phosphate, zanamivir, and peramivir.
Children who were less than 2 years of age, who had one or more chronic illnesses, had impaired immune function, who were morbidly obese, pregnant, were receiving long-term aspirin therapy, or had Native American heritage were identified as having a high risk for influenza-related complications.
In total, 24,795 (69%) were prescribed a neuraminidase inhibitor between 2007 and 2015, of which more than 99% were prescribed oseltamivir. Before the 2009 H1N1 pandemic, 20% of the child patients were prescribed a neuraminidase inhibitor compared to 69% afterward. In the 2014-2015 flu season, prescription rates ranged from 42% to 90% between the hospitals. Of the 35,909 hospitalized, 25,125 (70%) were considered at high risk for influenza-related complications – 70% of high-risk patients received neuraminidase inhibitors compared to 67% of those not at high risk.
The study’s findings suggest the prescription of anti-influenza medication in children is varied and generally below favourable levels in the United States. Barriers to widespread antiviral prescription may include concerns due to reports of mild to severe difficulty breathing when zanamivir is used in patients with severe asthma, the common side effects associated with neuraminidase inhibitors – in particular, nausea and vomiting with oseltamivir and diarrhea with peramivir – and the over-prescription of antibiotics (medications which kill or limit the growth of microorganisms such as bacteria, though not viruses) primarily due to misdiagnoses. As the researchers relied on specific diagnosis codes from hospital records, patients with severe influenza though hospitalized for different reasons, exposed to antiviral medications before hospitalization, or with risk factors for influenza-related complications coded differently may not have been fully accounted for. Further, clinicians may have forgone neuraminidase prescription if the perceived benefit was minimal (e.g. starting the drug after several days may have only shortened the illnesses’ duration by a day), especially for patients not at high risk for complications. Programs seeking to improve neuraminidase prescription rates may benefit from focusing on high-risk influenza patients, who are more likely to benefit from treatment.
Written By: Raishard Haynes, MBS