Questions and Answers with NAM Keith Alcorn, senior editor
What is bird flu and is it more dangerous for people with HIV?
Bird flu is an influenza virus called H5N1, spread from wild birds to farm
birds like chickens and ducks. It is widespread in birds in Asia, especially
China and Vietnam. It has been contracted by a very small number of humans
from these farm birds, but it is still very difficult to say whether the virus
has been transmitted from human to human.The H5N1 virus has been detected
in wild birds in eastern Europe and in quarantined, imported wild birds in
the UK. It appears to be spreading westwards from Asia.
Flu viruses generally come out of the wild bird population into humans, and
the most severe flu epidemics happen when humans encounter a completely new
strain of virus. This happened in 1918, when a very aggressive virus jumped
from birds to humans and spread round the world within six months, resulting
in millions of deaths. The H5N1 virus will only cause a similar pandemic today
if it becomes easily transmitted between humans. When H5N1 has caused disease
in humans it has focused on the lungs, where it causes severe damage, but
spreads to others with difficulty. However, the virus seems to need only one
change, or mutation, to become better adapted to the upper respiratory tract.
If it makes this change, H5N1 could be easily transmitted in the same way
as the human flu: by coughs, sneezes and runny noses.
What are the symptoms?
In the very small number of cases reported so far, the illness developed within
a few days of infection, and caused damage to the lungs. People have died
of pneumonia as a result. Very high fever, extreme fatigue and aches and pains
also accompany H5N1 infection. Approximately half of those infected with H5N1
have died. It is a very lethal flu virus.
Are people with HIV at higher risk?
We don’t know. People with HIV are recommended to have a flu vaccination
every winter because they are more vulnerable to flu and complications such
as bacterial pneumonia. However, there is speculation that H5N1 will be most
lethal in those with the strongest immune systems. There is also speculation
that people with suppressed immune systems will be less vulnerable, based
on the observation that a different type of respirtatory virus, SARS, did
not affect Aids patients receiving care in the same ward as SARS patients
in a Chinese hospital in 2003.
How can I protect myself?
In the same way as you would do against any other flu virus; by washing your
hands
frequently with soap and hot water, keeping your hands away from your nose,
eyes and mouth, and closing your eyes and turning away if someone sneezes
near you. Shaking hands or being kissed on the cheek are superb ways of catching
any flu virus.Cook poultry and eggs thoroughly, since H5N1 can be passed on
through eating. Wash your hands thoroughly any time you have contact with
poultry or wild birds, especially ducks and geese, even if an outbreak of
bird flu has not been reported in the UK.
I’ve been told to get a flu jab. Won’t that protect me?
The standard influenza vaccine on offer this winter will not protect you against
H5N1, but you should have it anyway. When a vaccine against H5N1 is available,
people with HIV and health care workers are likely to be prioritised to receive
it.
What about anti-flu drugs?
Tamiflu is a flu drug manufactured by Roche that reduces the severity of flu
symptoms. It seems to work in people with H5N1 infection, but as with ordinary
flu, it needs to be taken quickly after the symptoms develop to have much
effect. Another drug, Relenza, is available in inhaled form.
H5N1 isolated from humans in Vietnam this year shows signs of resistance to
Tamiflu compared to virus samples taken in Hong Kong several years ago, so
we don’t know how long it might remain effective.
Should I stock up on Tamiflu?
How? The drug is only available on prescription in the UK and you cannot be
certain that anything you buy over the internet will be genuine. You may be
able to buy the drug over the counter in other European countries. At best
it will reduce the symptoms, not stop the disease in its tracks, and there’s
no evidence that taking it while still healthy will prevent you from catching
influenza.
• NAM provides information to help you think about your use of HIV treatments,
but this is not intended to replace discussion with your doctor.
