# 921
With only enough pre-pandemic vaccine available to inoculate a few million people, a decision must be made on how best to utilize it.
There are two schools of thought. Give a very small number of people a full inoculation, and leave the rest of the country unprotected. Or, give as many people as possible a `little jab', with far less antigen, and hope it confers at least a little immunity.
How effective a full strength pre-pandemic vaccine will be is unknown. Viruses mutate, and a vaccine based on an older stain may confer little or no immunity. Diluting it will likely reduce its effectiveness even more.
But the choice here is to give the vaccine to perhaps 9 million Americans, and allow 290 million to go completely unprotected, or to dilute it enough to cover up to 160 million people. Half the country would still go without, but it might reduce the total number of infections.
Or it might not. Nobody really knows.
This from Reuters.
Stretch limited vaccines to fight pandemic-experts
Fri 22 Jun 2007 9:14:13 BST
By Tan Ee Lyn
HONG KONG, June 22 (Reuters) - Public health experts in Hong Kong are urging governments to stretch limited stockpiles of bird flu vaccines and lower the dosage used, arguing that such a strategy would reduce overall infection rates.Many pharmaceutical companies are designing "pre-pandemic" vaccines to fight what experts fear would be the next pandemic caused by the H5N1 bird flu virus, which could kill millions if it mutates into a strain that can pass easily between people.
But there is currently only capacity to make 350-400 million doses of flu vaccine, covering a fraction of the world's population of 6.6 billion.
Writing in the Public Library of Science journal PLoS Medicine, the researchers recommended using lower doses so that more people could be protected.
Using data on human immune responses to three experimental H5N1 vaccines and infection data from previous pandemics, the scientists developed a mathematical model.
"What our findings show is actually you should be giving less to more people given a certain stockpile," Gabriel Leung, an associate professor with the School of Public Health at the University of Hong Kong, said in a telephone interview.
"Yes, you are trading off a little bit of individual immunity. But overall, because more people are protected, the effect is that everybody ends up better off because of the indirect or 'herd immunity effect'."
