Bird Flu Compared with Common Flu

A new study in Vietnam throws some detailed light on why this flu is so deadly. It also stresses early treatment with Tamiflu.

http://www.abc.net.au/science/news/stories/2006/1737677.htm

http://news.yahoo.com/s/ap/20060910/ap_on_he_me/bird_flu_humans

http://article.wn.com/view/2006/09/11/Study_shows_need_for_early_use_of_Tamiflu/

AND FROM PANDEMIC NEWS:

Paris - New research conducted among bird flu victims in Vietnam
shows the H5N1 virus replicates massively before unleashing a
dangerous inflammatory response by the immune system, indicating
that patients should be given antiviral drugs as soon as possible.

Published online Sunday by the journal Nature Medicine, the study
focuses on 18 Vietnamese who caught bird flu in 2004 and 2005, 13
of whom died.

Samples were taken from these patients to assess the level of H5N1
virus in the throat, and compared with other patients who had two
strains of ordinary human flu.

H5N1 patients had much higher viral loads than counterparts with
the human virus. In addition, high levels of H5N1 also triggered a
"dysregulation" of cytokines - messenger proteins in the immune
system - which in turn caused inflammation and worsened the
patient's condition.

"The focus of clinical management should be on preventing this
intense cytokine response, by early diagnosis and effective
antiviral
treatment," says the paper, lead-authored by Menno de Jong of the
Oxford University Clinical Research Unit in Ho Chi Minh City,
Vietnam.

The antiviral of choice in fighting H5N1 is oseltamivir, which
is made
by the Swiss group Roche and commercialised under the brand Tamiflu.

Tamiflu is not a cure for flu. It brakes replication of the virus,
thereby
easing inflammation which is the cause of most flu symptoms and
speeding the time to recovery.

Roche recommends that Tamiflu be administered within 48 hours to
treat ordinary seasonal human flu, and says work is under way to
fine tune treatment for bird flu.

Millions of doses of Tamiflu are being stockpiled by governments
and the World Health Organisation in the event of a global
flu pandemic.

Some experts warn against over-reliance on Tamiflu, fearing
that the
drug could be of limited use if the H5N1 virus, at present
transmissible
from birds to humans, mutates into a form that could make it easily
contagious among humans.

In the Vietnam study, 17 of the 18 cases received Tamiflu.
The drug
appears to have had little effect, but probably because
it was
administered too late to prevent the cytokine cascade,
the paper
said. - Sapa-AFP