# 2319
Pre-pandemic vaccines - in this case, vaccines based on an existing strain of the H5N1 virus - are hoped will provide at least some protection, even against a mutated avian flu virus.
How much protection is an open question.
Perhaps not enough to prevent infection (although that would be nice), but hopefully enough to moderate the effects of the illness and reduce the mortality rate.
If nothing else, it is hoped that such vaccinations might `prime' a recipient's immune system to allow them to need only one booster shot during a pandemic.
Japan, which currently has about 20 million doses of a soon-to-expire pre-pandemic vaccine, is contemplating inoculating millions of their healthcare and critical infrastructure employees early next year.
Switzerland has reportedly purchased 8 million doses of pre-pandemic vaccine, enough to inoculate their entire citizenry should they choose. Denmark, it was widely reported in January of 2007, ordered in enough pre-pandemic vaccine for half of their population. And in Australia, there has been talk of inoculating their entire nation.
New Zealand has announced they had enough pre-pandemic vaccine on hand for 100,000 essential workers, and the UK is exploring the purchase of large quantities of vaccine.
The United States reportedly has enough pre-pandemic vaccines, based on several earlier clades of the H5N1 virus, to inoculate about 20 million essential workers.
While the WHO (World Health Organization) has stopped short of recommending that countries stockpile a pre-pandemic vaccine obviously not all nations agree.
Pulling the trigger, however - actually distributing this vaccine before a pandemic erupts - is not an easy decision. There are always worries that there could be a small number of serious side effects when millions of shots are given.
Acceptable in the face of a deadly pandemic, but less so when this is a prophylactic move for a pandemic that hasn't started.
Today, we get a detailed opinion piece in the The Lancet Infectious Diseases journal, supporting the idea of early pre-pandemic vaccinations, particularly among high risk populations.
As the author's point out, once a pandemic begins it will become more difficult to deliver a pre-pandemic vaccine to the population. They go so far as to suggest :
The maximum benefit from using a prepandemic vaccine may be gained from priming populations before phase 4, when systematic supply, distribution, and vaccination strategies can be put in place.
There is a good deal of information presented here, and it is well worth reading it in its entirety.
The abstract may be freely read, but registration (it's free) is required to read the entire journal article.
I've reproduced the abstract below (reparagraphed for readability).
The Lancet Infectious Diseases 2008; 8:650-658
DOI:10.1016/S1473-3099(08)70232-9
Personal View
Stockpiling prepandemic influenza vaccines: a new cornerstone of pandemic preparedness plans
Dr Lance C Jennings PhD , Prof Arnold S Monto MD , Prof Paul KS Chan MD , Prof Thomas D Szucs MD and Prof Karl G Nicholson MD
Summary
The history of pandemic influenza, along with the evolving epizootic of the highly pathogenic avian influenza A (H5N1) virus and the severity of associated human infections, serve as a warning to the world of the threat of another influenza pandemic.
Conservative estimates suggest that up to 350 million people could die and many more would be affected, causing disruption to health-care systems, society, and the world's economy.
WHO has encouraged countries to prepare in advance by developing influenza pandemic preparedness plans that involve public-health and pharmaceutical interventions.
Vaccination is a cornerstone of these plans; however, a pandemic vaccine cannot be manufactured in advance because the next pandemic virus cannot be predicted.
The concepts of vaccine stockpiling and prepandemic vaccination have thus become attractive. Human H5N1 vaccines are currently available and can induce heterotypic immunity.
WHO and governments should give urgent consideration to the use of these vaccines for the priming of individuals or communities who would be at greatest risk of infection if an H5N1 influenza pandemic were to emerge.
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