final program.qxd - Parallels Plesk Panel

OP 8.3
Epidemiology and Control of Avian Influenza
Arjan Stegeman
Faculty of Veterinary Medicine - Department of Farm Animal Health
Introduction
Infections with Avian Influenza (AI) viruses are common in various mammal and bird
species. AI is a notifiable animal disease (OIE), and outbreaks of AI were reported for
decades in several countries, such as Mexico, Italy, The Netherlands, and Canada. Until
a few years ago, AI, or fowl plague, was mainly considered being a veterinary problem,
causing high mortality in poultry and severe economic damage for the poultry industry.
Since the outbreaks of high pathogenicity (HPAI) H5N1 in Asia in 1997, however, AI also
attracted the attention of public health organizations, as this strain caused the death of
over 100 persons, and multiple numbers distracted the infection. Scientists are warning for
a new influenza pandemic, and nowadays, the disease seems to be more a human
health issue than a veterinary one.
ABSTRACTS
It should not be forgotten, however, that, at least until this moment, the disease mainly
affected poultry and other birds. Especially the poultry industry in Asian countries, like
Thailand, Vietnam, Cambodia, Indonesia and others, is struck by AI epidemics. Everyone
saw pictures of desperate farmers and their families, farms being depopulated, people
carrying bags full of chickens and throwing them into pits. The outbreaks seemed to be
limited to this part of the world, but last year, the virus also spread to countries in the
western hemisphere, such as Russia, Turkey, Romania, Slovenia, Germany, France and
many other. These outbreaks were controlled rather quickly and relatively few farms
became infected.
In addition to this, it should be realized that other HPAI strains than H5N1 may emerge,
and may cause epidemics in poultry or a new human pandemic. This year, Europe only
had localized outbreaks of H5N1, but three years ago, The Netherlands was confronted
with a huge epidemic of H7N7, during which 30 million poultry were killed and one
veterinarian died. So we know how devastating an AI infection for the poultry industry can
be, and how large the impact is on the society.
Because of the devastating effect for poultry and the possible public health risk, outbreaks
of HPAI should be controlled as quickly as possible. From a veterinary perspective, but
also from a human health point of view, the disease should be controlled at the source,
i.e. the poultry farm. Especially, prompt reduction of the virus output is very important, with
respect to reduction of the exposure for poultry and humans.
Control of AI
To stop epidemics of HPAI, knowledge of the effectiveness of the control measures
implemented during an epidemic is of vital importance. Four issues that are logically
related to the epidemiology of Avian Influenza will be addressed, mainly with respect to
the Dutch epidemic.
“ Focusing FIRST on PEOPLE “ 65 w w w . i s h e i d . c o m