Avian influenza A H7N9: Treatment and prevention
- Anna R Thorner, MD
Anna R Thorner, MD
- Deputy Editor — Infectious Diseases
- Assistant Professor of Medicine, Part-time
- Harvard Medical School
In late March and April 2013, human cases of severe pneumonia caused by novel avian influenza A H7N9 infection in China were reported to the World Health Organization [1-7]. The number of new cases in the first wave peaked in April and then decreased , likely related, at least in part, to implementation of control strategies including closure of live bird markets and increased public awareness. A rise in the number of cases occurred in late 2013 and early 2014 as well as in late 2014 and early 2015, coinciding with influenza season.
The treatment and prevention of avian influenza A H7N9 infections will be reviewed here. The epidemiology, clinical manifestations, and diagnosis of avian influenza A H7N9 infections are discussed separately. (See "Avian influenza A H7N9: Epidemiology, clinical manifestations, and diagnosis".)
Other avian influenza viruses (eg, H5N1 influenza) and seasonal influenza viruses are also reviewed separately. (See "Epidemiology, transmission, and pathogenesis of avian influenza" and "Clinical manifestations and diagnosis of avian influenza" and "Treatment and prevention of avian influenza" and "Avian influenza vaccines" and "Epidemiology of influenza" and "Clinical manifestations of seasonal influenza in adults" and "Diagnosis of seasonal influenza in adults" and "Seasonal influenza in children: Clinical features and diagnosis" and "Treatment of seasonal influenza in adults" and "Seasonal influenza in children: Prevention and treatment with antiviral drugs" and "Seasonal influenza vaccination in adults" and "Seasonal influenza in children: Prevention with vaccines".)
Avian influenza A H7N9 virus appears to be resistant to the adamantanes (amantadine and rimantadine) but currently susceptible to the neuraminidase inhibitors (oseltamivir and zanamivir) [5,9,10]. However, an arginine-to-lysine mutation at position 292 of the neuraminidase protein has been detected in several clinical isolates [4,5,11-13]. This mutation has been associated with in vitro resistance to neuraminidase inhibitors in another N9 influenza virus .
The United States Centers for Disease Control and Prevention (CDC) released updated treatment guidelines for avian influenza A H7N9 infection on September 30, 2013 . The recommendations below are in accordance with the CDC’s guidelines. Clinicians should check the CDC website for updated recommendations.
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- Gao HN, Lu HZ, Cao B, et al. Clinical findings in 111 cases of influenza A (H7N9) virus infection. N Engl J Med 2013; 368:2277.
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- Mulligan MJ, Bernstein DI, Winokur P, et al. Serological responses to an avian influenza A/H7N9 vaccine mixed at the point-of-use with MF59 adjuvant: a randomized clinical trial. JAMA 2014; 312:1409.
- Jackson LA, Campbell JD, Frey SE, et al. Effect of Varying Doses of a Monovalent H7N9 Influenza Vaccine With and Without AS03 and MF59 Adjuvants on Immune Response: A Randomized Clinical Trial. JAMA 2015; 314:237.
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- Yu H, Cowling BJ, Feng L, et al. Human infection with avian influenza A H7N9 virus: an assessment of clinical severity. Lancet 2013; 382:138.
- General recommendations
- Hospitalized patients
- - Dosing
- - Duration
- Uncomplicated illness in outpatients
- - Dosing
- - Duration
- Neuraminidase inhibitor resistance
- Infection control
- Postexposure prophylaxis
- Treatment of symptomatic close contacts
- Patients who develop symptoms after use of an antiviral agent
- Follow-up of close contacts
- Vaccine development
- Travel information
- SUMMARY AND RECOMMENDATIONS