title: Developments in the treatment of severe influenza: lessons from the pandemic of 2009 and new prospects for therapy.
abstract: OBJECTIVE
  Cases of severe influenza may occur during seasonal epidemics, following sporadic zoonotic influenza A transmission from animal reservoirs or on a massive scale with the unpredictable emergence of a new pandemic influenza strain. Clinical experience identifies unmet medical need for additional therapies for influenza, in particular to treat severely unwell adults and children. During and following the pandemic of 2009, a wealth of data from hospitalized cases of influenza from many different countries accumulated and are now starting to emerge. Observational clinical data provide information about the efficacy of existing antiviral drugs in severely ill patients. The development pipeline for new therapies contains several promising agents which are focussed on a range of viral targets, and opens the possibility of combination antiviral therapy for the first time, which may be especially useful in clinically challenging cases. Advances in immunological methods and recombinant protein engineering support the potential for use of immunomodulating therapies as adjuncts in treatment of severe influenza.
  
  
  RESULTS
  The main themes are the importance of treating severe influenza early, considering multiple therapy options and the relevance of observational clinical data to treatment of severely ill and risk groups.
  
  
  CONCLUSIONS
  Clinicians, who may have only seen the media headlines following discussion of reviews which deal with randomized controlled trials of neuraminidase inhibitor drug use in mild uncomplicated influenza in the community, may be hesitant to prescribe these drugs. Observational data arising from treatment of severely ill individuals support use of these drugs early in illness and show improvement in outcomes associated with drug use.
authors.affiliation: Microbiology Services, Public Health England, London, UK.
authors.forename: Maria
authors.initials: M
authors.lastname: Zambon
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001717:Birds; D004791:Enzyme Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use; D005585:Influenza in Birds / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D007251:Influenza, Human / Q000188:drug therapy* / Q000453:epidemiology / Q000276:immunology; D009439:Neuraminidase / Q000037:antagonists & inhibitors*; D053139:Oseltamivir / Q000009:adverse effects / Q000627:therapeutic use; D058873:Pandemics; D011159:Population Surveillance; D011634:Public Health; D016032:Randomized Controlled Trials as Topic; D053243:Zanamivir / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D000998:Antiviral Agents; D004791:Enzyme Inhibitors; D007155:Immunologic Factors; D053139:Oseltamivir; D009439:Neuraminidase; D053243:Zanamivir