According to the CDC and WHO, for patients with uncomplicated seasonal influenza, treatment should focus on management of symptoms, such as fever.16,23 The CDC recommends antiviral treatment as early as possible for patients who are hospitalized; have severe, complicated, or progressive illness; or are at higher risk for influenza complications. This includes patients with exacerbations of underlying chronic medical conditions.23 Treatment also can be considered for symptomatic patients with household contacts at high risk for complications.24
The initiation of antiviral medications should not be delayed pending laboratory confirmation of suspected infections. Ideally, treatment should be started within 48 hours of symptom onset but it may be considered later in the course of illness based on the patient’s presentation.23 Studies have shown that early treatment of influenza with antiviral medications reduces duration of symptoms, risk for complications (bronchitis, otitis media, pneumonia), and hospitalizations.24-25 It may decrease mortality among high-risk populations.24 According to the WHO and Infectious Diseases Society of America (IDSA), treatment should be given for a minimum of 5 days, but it can be continued beyond that until there is satisfactory clinical improvement.16,24
The CDC recommends 4 FDA-approved antiviral medications for outpatient treatment of influenza: oral oseltamivir, inhaled zanamivir, intravenous peramivir, and oral baloxavir (Table 2). Oseltamivir is the recommended antiviral for patients with severe, complicated, or progressive illness, as well as pregnant women.
In the United States, rates of resistance to these medications are currently low.25 During influenza season, monitor the CDC for guidance on influenza resistance to the current circulating viruses because this may affect treatment plans.25
The WHO and IDSA recommend against the routine use of corticosteroids in the treatment of influenza unless they are indicated for other reasons, such as asthma exacerbation.16,24 Corticosteroids have been associated with prolonged viral clearance as well as immunosuppression leading to bacterial or fungal superinfections.16,24
During the 2020-2021 influenza season, providers will need to keep a broader differential diagnosis for patients with upper respiratory symptoms. COVID-19 and influenza can present very similarly. Even in patients with a positive flu test, COVID-19 must be kept in mind because patients can present with co-infection. Prevention strategies for both illnesses include frequent handwashing, social distancing, and self-quarantine. Encouraging patients to get a flu vaccine is especially important to help decrease the disease burden on our health care system.
Jessica Kovalchick, RPA-C, is a physician assistant specialist working in Owego, New York.
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11. Centers for Disease Control and Prevention. Influenza (flu). Frequently asked influenza (flu) questions: 2020-2021 season. Centers for Disease Control and Prevention website. https://www.cdc.gov/flu/season/faq-flu-season-2020-2021.htm. Updated July 28, 2020. Accessed August 2, 2020.
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16. World Health Organization. Influenza (season). Ask the expert: influenza Q&A. https://www.who.int/en/news-room/fact-sheets/detail/influenza-(seasonal). World Health Organization website. Published November 6, 2018. Accessed August 2, 2020.
17. Centers for Disease Control and Prevention. Influenza (flu). Flu symptoms & diagnosis. https://www.cdc.gov/flu/symptoms/index.html. Centers for Disease Control and Prevention website. Updated July 10, 2019. Accessed August 2, 2020.
18. World Health Organization. Coronavirus. https://www.who.int/health-topics/coronavirus#tab=tab_3. World Health Organization website. Published 2020. Accessed August 2, 2020.
19. Lauer SA, Grantz KH, Bi Q, et al. The incubation period of coronavirus disease 2019 (COVID-19) from publicly reported confirmed cases: estimation and application. Ann Int Med. 2020;172(9):577-582.
20. Tang X, Rong-Hui D, Wang R, et al. Comparison of hospitalized patients with ARDS caused by COVID-19 and H1N1. Chest. 2020;158(1):195-205.
21. Shen, C, Tan M, Song X, et al. Comparative analysis of early-stage clinical features between COVID-19 and influenza A H1N1 virus pneumonia. Front Public Health. 2020;8:206.
22. Ma S, Lai X, Chen Z, Tu S, Qin K. Clinical characteristics of critically ill patients co-infected with SARS-CoV-2 and the influenza virus in Wuhan, China. Int J Infect Dis. 2020;96:683-687.
23. Centers for Disease Control and Prevention. Influenza (flu). Influenza antiviral medications. https://www.cdc.gov/flu/professionals/antivirals/index.htm. Centers for Disease Control and Prevention website. Updated July 13, 2020. Accessed August 2, 2020.
24. Uyeki TM, Bernstein HH, Bradley JS, et al. Clinical practice guidelines by the infectious diseases society of America: 2018 update on diagnosis, treatment, chemoprophylaxis, and institutional outbreak management of seasonal influenza. Clin Infect Dis. 2019;68(6):e1-e47.