Intravenous zanamivir in critically ill patients due to pandemic 2009 (H1N1) influenza A virus

Wijaya L, Chua YY, Cui L, Chan K, Tan BH
Correspondence: Dr Limin Wijaya, limin.wijaya@sgh.com.sg

ABSTRACT
Introduction The 2009 (H1N1) influenza A pandemic started in april 2009 and has since spread globally. We have noticed that critically ill patients with confirmed pandemic 2009 (H1N1) influenza A require mechanical ventilation. This paper describes the use of intravenous zanamivir in this group of patients.
Methods Patients who had severe pneumonia with 2009 (H1N1) influenza A and required intravenous zanamivir were referred to the Infectious Diseases Department of our institution. Clinical data was collected from these patients. Clinical samples were sent to the National Public Health Laboratory for sequencing.
Results A total of five patients used intravenous zanamivir from April 8 to May 8, 2010. Only one death was reported. There were no side effects attributable to the use of intravenous zanamivir. H275 mutation, which confers resistance to oseltamivir, was seen in a subpopulation of the virus in one case.
Conclusion Physicians can consider using intravenous zanamivir for the treatment of critically ill patients with 2009 (H1N1) influenza A infection.

Keywords: H1N1 virus, influenza, intensive care unit, pneumonia, zanamivir
Singapore Med J 2011; 52(7): 481-485