Medical News Today, Article Date: 08 May 2006
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In a CNN interview, Michael Leavitt, US HSS Secretary, said the United States is not yet prepared for a flu pandemic. He added that it would not surprise him if the H5N1 bird flu virus strain made its way to the USA within the next few months.
Over the last year the H5N1 strain has spread from South East Asia to Western Europe and West Africa.
Last week the American government awarded $1 billion to five pharmaceutical companies to develop a vaccine to combat the effects of a flu pandemic. The money is also aimed at making America less dependent on foreign supplies of flu vaccines.
On June 6-7 the USA and the European Union will meet in Vienna, Austria, to review plans to combat bird flu and the possible human flu pandemic that could emanate.
Michael Leavitt warned that he saw no reason why the USA should be spared the consequences of a flu pandemic. He referred to the Spanish Flu of 1918, which killed an estimated 40 million people around the world.
The present H5N1 bird flu strain has killed about half of the 200 people who have become infected since 2003. It does not infect humans easily when compared to the approximately 200 million birds that have died of avian flu since 2003.
The main reason bird flu does not infect humans easily is that it needs to get deep down into the lungs, into the lower-respiratory tract, to make a human ill. For this to happen the human needs to be surrounded by a large cluster of H5N1. This can only happen if a human is in continuous, close proximity to sick birds. Even then, infection is rare.
An infected person very rarely infects another person. Mainly because, at the moment, the infection can only take place way down in the lower-respiratory tract. An infected patient who coughs and sneezes does not expel enough of the virus to pose a threat to those around him. There have been some very rare cases of humans infecting others - people caring for an infected person, staying very close to them for many days - but the risk of human-to-human transmission is extremely rare.
For the virus to become human transmissible - it needs to infect the upper-respiratory tract, nearer the throat. Then coughs and sneezes would expel large numbers of the virus. Also, if the virus managed to infect the upper-respiratory tract, it would make people ill more easily. For the virus to switch from infecting only deep down to infecting nearer the throat, it would need to mutate.
However, it is not all bad news. If the virus did mutate and managed to infect nearer the throat, doctors would be able to treat and cure sick people more easily for two reasons. 1. Symptoms would appear earlier. The earlier a person is treated the more likely they are to survive. 2. An upper-respiratory tract infection is generally less dangerous than a lower-respiratory tract infection.
Therefore, if a flu pandemic did break out, hopefully we would be dealing with a disease which is not as deadly as the present H5N1 infection, even though it would spread among humans more easily.
Written by: Christian Nordqvist
Editor: Medical News Today