British Medical Journal
26 February 2011 Volume 342, Issue 7795
http://www.bmj.com/content/current

Editorials
Pandemic influenza vaccines
John M Watson, Richard G Pebody
BMJ 342:doi:10.1136/bmj.d545 (Published 8 February 2011

Extract
Are protective, but are limited by delays in availability

Almost as soon as the new influenza A/H1N1 2009 virus was identified in April 2009, its pandemic potential was realised. 1 Immediate steps were taken by vaccine manufacturers, working with the World Health Organization’s network of influenza reference laboratories, and with regulatory and standardisation authorities, to develop a pandemic specific vaccine and manufacture enough to meet global needs. To make best use of the H1N1 antigen, low dose monovalent vaccines were developed with the addition of adjuvant to enhance immunogenicity. These vaccines became available towards the end of 2009. The first of several studies to assess the effectiveness of these pandemic influenza A/H1N1 vaccines, including the linked study (doi: 10.1136/bmj.c7297 ) by Skowronski and colleagues, 2 are now being published.

On the basis of the emerging epidemiological picture, pandemic vaccines were given to subsets of the population at higher risk of infection and severe disease according to national immunisation policies. In the United Kingdom, people with underlying health conditions that place them at increased risk from the complications of influenza, including those aged 65 years and over …