Strategies for distributing limited supplies of avian flu vaccine

One of the most difficult public health and ethical questions a potential flu pandemic raises is how best to allocate limited supplies of vaccine (which will only be of limited effectiveness at first, as we've written previously). There's general consensus that first responders or other 'essential personnel' (the definition of which varies widely) should be a top priority, including hospital staff, police, firefighters, top government leaders, etc.

Eventually, though, the focus shifts to larger segments of the population, and the key question becomes how to equitably distribute vaccine supplies while most effectively combating the virus' spread. According to this story in today's Seattle Times, flu researches Ira Longini and Elizabeth Halloran have an answer: school-aged children...

"At school, kids are close together, they don't practice the best hygiene, and they help germs spread like pollen in spring. At home, they do the same with their families.

Giving them the best available vaccine at the earliest sign of a major epidemic might fend off a deadly pandemic, say two of the nation's most prominent influenza researchers, newly arrived at the Fred Hutchinson Cancer Research Center.

'A lot of people believe kids are the best transmitters of the virus, and with a limited supply of vaccine, this might work,' said Elizabeth Halloran, who has studied epidemics for decades.

Halloran and her colleague, Ira Longini, believe using available vaccine would buy time for manufacturers to create a vaccine that matches the pandemic flu virus exactly and would protect millions of people worldwide."

Ask any teacher and they (and their immune system) will agree that school-age children are highly effective vectors of bacteria and viruses. This public health strategy is not new in itself and has implications reaching well beyond avian flu. As in most discussions of vaccines, the challenge is weighing individual benefits versus societal good. Children may be a common vector of transmission, but their immune systems are (generally) better equipped to fight off infections. Thus, alternative strategies suggest vaccinating the elderly, the immunocompromised, pregnant women, and other groups that individually are more susceptible to the effects of infections.

The story in today's Seattle Times actually references a Science paper published by Halloran and Longini back in February. (Science, 3 February 2006, 311:615-616 -- subscription required). In the paper, the authors call for increased research of vaccinating schoolchildren against seasonal flu in order to better understand the impact of such a strategy in limiting transmission.

Speaking of Science, the current (April 21) issue is devoted entirely to influenza and is available free (with registration). In an introduction to the issue titled "Influenza: The State of Our Ignorance," Caroline Ash and Leslie Roberts write,

"An energetic response to H5N1 does not have to be alarmist. We can marshal existing concern about this particular strain of avian influenza to build a long-lasting international infrastructure to monitor and thwart threats from such emerging infections."

Agreed.