Influenza in the Emergency Department: 2020 Update (Pharmacology CME)

Points & Pearls Excerpt

• The CDC defines influenza-like illness (ILI) as a temperature > 37.8°C (100°F), with either cough or sore throat, in the absence of a known cause other than influenza.
• The most common symptoms of influenza in adults are cough, fatigue, nasal congestion, and fever.
• Sneezing is a negative predictor in adults.
• In children, the most common presenting symptoms are fever, cough, and rhinitis. Vomiting and diarrhea are more common in children than adults.
• When influenza is suspected in the prehospital setting, patients and providers should wear face masks to avoid spreading the virus.

Most Important References

• Peltola V, Ziegler T, Ruuskanen O. Influenza A and B virus infections in children. Clin Infect Dis. 2003;36(3):299-305. (Retrospective study; 15,420 patients)
• Lim WS. Pandemic flu: clinical management of patients with an influenza-like illness during an influenza pandemic. Tho-rax. 2007;62(suppl1):1-46. (Clinical practice guidelines-UK)
• Uyeki TM. Influenza diagnosis and treatment in children: a review of studies on clinically useful tests and antiviral treatment for influenza. Pediatr Infect Dis J. 2003;22(2):164-177. (Systematic review)
• Stein J, Louie J, Flanders S, et al. Performance characteristics of clinical diagnosis, a clinical decision rule, and a rapid influenza test in the detection of influenza infection in a community sample of adults. Ann Emerg Med. 2005;46(5):412-419. (Prospective study; 258 patients)
• Lee J, Park JH, Jwa H, et al. Comparison of efficacy of intravenous peramivir and oral oseltamivir for the treatment of influenza: systematic review and meta-analysis. Yonsei Med J. 2017;58(4):778-785. (Systematic review; 1676 patients)
• Jefferson T, Demicheli V, Rivetti D, et al. Antivirals for influenza in healthy adults: systematic review. Lancet. 2006;367(9507):303-313. (Systematic review; 51 RCTs)
• Jefferson T, Demicheli V, Di Pietrantonj C, et al. Amantadine and rimantadine for influenza A in adults. Cochrane Database Syst Rev. 2006 Apr 19;(2):CD001169. (Cochrane review; 20 prophylaxis trials, 13 treatment trials) 
• Muthuri SG, Venkatesan S, Myles PR, et al. Effectiveness of neuraminidase inhibitors in reducing mortality in patients admitted to hospital with influenza A H1N1pdm09 virus infection: a meta-analysis of individual participant data. Lancet Respir Med. 2014;2(5):395-404. (Meta-analysis of data from 2009-2010 pandemic; 78 studies, 29,234 patients)