About Intervet
Background information on Avian Influenza outbreak
11 March 2003
General background information
Boxmeer, March 11, 2003 – On March 1, 2003, the Dutch government decided to place a ban on all transport and export of poultry and poultry related farming products following a suspicion of an avian influenza outbreak in various Dutch poultry farms. A leading producer of veterinary vaccines, Intervet is able to help the Dutch government and poultry farms control this serious outbreak wherever necessary. The Netherlands is one of the main chicken and egg exporters in Europe. A long-term poultry-trading ban will have grave economic consequences for poultry farmers. Vaccination against avian influenza is, in principle, possible and is administered in various countries. Europe, however, prefers vaccine-free control in order to prevent further trading restrictions.
The current infection is caused by the avian influenza virus, type A, subtype H7N7, as confirmed by the Central Institute for Animal Disease Control (CIDC) on March 4. In cases of emergency, Intervet International bv can produce inactivated avian influenza vaccines based on various subtypes, including this subtype H7. In addition to the protective hemagglutinin factor H7, the vaccine contains neuraminidase factor N1. This makes it possible, in theory, to distinguish vaccinated birds with H7N1 from birds infected with the field strain H7N7. This marker principle is essential for monitoring the further development of the outbreak. A test that can be used routinely to discriminate between the neuraminidase factors N7 and N1 is unavailable at present. The vaccine containing N1 is currently used in Italy to control an infection caused by another subtype (H7N3). Here a discriminatory test is available to distinguish the vaccine strain N1 from the field strain N3. Furthermore the concerned region in Italy is not an explicit export region.
What is avian influenza? Is it also dangerous to human beings?
A good overview is given by the fact sheet of the European Commission: http://www.europa.eu.int/comm/food/fs/ah_pcad/ah_pcad_76_en.pdf
Further information can be found on the internet site of the Dutch Ministry of Agriculture, Nature Management and Fisheries: http://www.minlnv.nl/international/
[Avian influenza is an infection caused by influenza viruses (orthomyxoviruses) and can occur in many forms, ranging from non-pathogenic to highly pathogenic, as is the case with the current outbreak in the Netherlands. There are various types, but the disease in poultry is caused by type A, which may occur in various subtypes. The viruses are classified according to the important viral proteins, hemagglutinin H and neuraminidase N. The present infection appears to be caused by the highly pathogenic H7N7 variant. A less pathogenic subtype (H7N3) was responsible for the most recent European outbreak, in Northern Italy.
In an outbreak with highly pathogenic virus, infected animals display considerable clinical symptoms, leading to extremely high mortality (up to 100%). As is the case with human influenza, there are respiratory symptoms, but also damage to the central nervous system, diarrhea, yawning and swollen heads and combs.
Avian influenza generally only affects birds, particularly chickens and turkeys, but also waterfowl, such as ducks and geese. Pigeons are not susceptible, but can be passive virus transporters. The type of virus observed in the Gelderse Vallei area poses little risk to humans. It is known that infection cannot be entirely ruled out for people who work intensively with large numbers of chickens, such as poultry farmers (source: Dutch Food and Non-Food Authority). The last known case of infection with an H5 subtype was in February 2003 in Hong Kong, after a child had been in direct contact with contaminated chickens.]
What is the current situation?
For the present state of affairs, we refer to the Ministry of Agriculture, Nature Management and Fisheries:http://www.minlnv.nl/international/
What measures are being taken to prevent the disease from spreading?
For the present state of affairs, we refer to the Ministry of Agriculture, Nature Management and Fisheries:http://www.minlnv.nl/international/
[If avian influenza is suspected, the first steps to be taken are to isolate the companies involved and destroy the infected animals. Roads are closed and all transport and visits are prohibited. Secondly, an initial protection zone with a 3-kilometer radius and a supervision zone with a 10-kilometer radius are designated, in which certain measures are being taken as well to prevent expansion of the infection.]
What consequences can poultry farmers expect?
For the present state of affairs, we refer to the Ministry of Agriculture, Nature Management and Fisheries:http://www.minlnv.nl/international/
Are there no alternative measures to standstill and killing animals?
Vaccination against avian influenza is possible and is in fact practiced in a number of countries. Intervet is already using a number of avian influenza vaccines in other parts of the world. In Europe, vaccine-free control is the preferred method to begin with, in order to avoid further trade bans. Member states of the European Union require the European Commission’s approval for vaccination. During an outbreak, ring vaccination or regional vaccination can be used to prevent the virus from spreading or in cases where there is insufficient destruction capacity. During the recent outbreak in Italy, for example, the authorities requested permission for vaccination within a certain area.
The current infection is caused by the avian influenza virus, type A, subtype H7N7, as confirmed by the Central Institute for Animal Disease Control (CIDC) on March 4. In cases of emergency, Intervet International bv can produce inactivated avian influenza vaccines based on various subtypes, including this subtype H7. In addition to the protective hemagglutinin factor H7, the vaccine contains neuraminidase factor N1. This makes it possible, in theory, to distinguish vaccinated birds with H7N1 from birds infected with the field strain H7N7. This marker principle is essential for monitoring the further development of the outbreak. A test that can be used routinely to discriminate between the neuraminidase factors N7 and N1 is unavailable at present. The vaccine containing N1 is currently used in Italy to control an infection caused by another subtype (H7N3). Here a discriminatory test is available to distinguish the vaccine strain N1 from the field strain N3. Furthermore the concerned region in Italy is not an explicit export region. Therefore, during the last outbreak of the virus, Italy has requested and received consent to vaccinate in a restricted area.
Is the correct vaccine available in sufficient quantities?
Intervet has an active virus strain in stock. Should, at a certain moment, consent to vaccinate be given, the delivery time will depend on the requested amounts.
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Note for the editor:
Intervet, a business unit of Akzo Nobel, headquartered in Boxmeer, The Netherlands, with sales of EUR 1.081 million in 2002, is focused on the research and development, manufacturing and marketing of veterinary products. Products include vaccines for the prevention of infectious diseases, anti-infectives, anti-parasitics and products for fertility management. All of these products are intended for use in a variety of animal species, including poultry, pigs, cattle, sheep, goats, horses, fish and companion animals. Intervet operates globally with its own marketing organizations. The company currently employs around 5,000 people.
Akzo Nobel, based in the Netherlands, serves customers throughout the world with healthcare products, coatings and chemicals. Consolidated sales for 2002 totaled EUR 14 billion. The Company currently employs approximately 68,000 people in more than 80 countries. Financial results for the first quarter will be published on April 16, 2003.
For further information please contact:
Sabine Schueller
Communications & Public Affairs
Intervet International bv
Tel: +31 (0)485 587085
Fax: +31 (0)485 585392
communications@intervet.com