Further information about an outbreak of Newcastle Disease in Sweden has emerged.
As stated in the emergency report, Sweden received confirmation on July 20, 2004, of the presence of Newcastle Disease virus in a sample collected in a holding of laying hens in the County of Ostergotland ( central east coast of Sweden), and the same virus was detected in another farm, situated approximately 500 metres from the farm where the infection was first detected.
Dr Leif Denneberg, Chief Veterinary Officer, Swedish Board of Agriculture, Jˆnkˆping, said: "Based on the epidemiological investigations carried out, there is still no reason to believe that the virus has spread from the two affected holdings.
"On condition that no further suspicion or outbreak is detected within the protection and surveillance zones, both zones will be lifted on August 4, 2004, 30 days after completion of preliminary cleaning and disinfection."
Dr Denneberg said that the source of infection for the first affected farm was still unknown, but suspected to be wild birds. Personal contact is the suspected mode of transmission to the second farm."
He added: "Up to now, no further suspicion of infection with Newcastle Disease have been noted in the protection and surveillance zones. Following advertisements in the regional and local newspapers, owners have reported the presence of three additional hobby flocks in the surveillance zone; there is no suspicion of disease in these flocks. "Due to increased vigilance among farmers during the previous week, two hobby flocks situated outside the restriction zones (but in the County of Ostergotland) were reported as having clinical signs that could indicate Newcastle Disease. Both flocks were put under restrictions immediately on suspicion. The investigations that were carried out, including clinical examination and serology (samples taken after an appropriate time to allow for possible seroconversion), ruled out the presence of Newcastle Disease. Accordingly, the restrictions on these farms have been lifted."
Dr Denneberg said that the poultry at both infected farms had been slaughtered and rendered already on suspicion (when antibody titres against paramyxovirus-1 were detected) - ie, on June 21 and July 1, respectively. Preliminary cleaning and disinfection of the farms had finished on June 21 and July 4.
The complete cleaning and disinfection is now ongoing on both farms.
"Upon suspicion of the disease, Sweden already took even more stringent measures than those laid down in European Union legislation in order to control the outbreak as soon as possible and stop any further spread of the disease," he said.
"According to European Union legislation, Sweden, with the exception of the established control and surveillance zones situated in the County of Osteragotland, is to be regarded as free from Newcastle Disease."
Vaccination of poultry against Newcastle Disease is prohibited in Sweden.
No further outbreaks of Newcastle Disease have been reported in Finland.
An outbreak was confirmed in the middle of July. All birds on the infected holding, 12,000 turkeys in total, were killed and completely destroyed on July 22, 2004.
Dr Riitta Heinonen, Deputy Director General, Veterinary and Food Department, Ministry of Agriculture and Forestry, Helsinki, said: "Serological screening has been carried out in poultry holdings in the protection zone, the surveillance zone and the immediate area surrounding them (nine holdings in total).
"To date, all the results have been negative. Serological screening is continuing and all poultry holdings in the protection and surveillance zones will be tested before the zones are lifted.
"An epidemiological enquiry including backward and forward tracing has been completed. Only one contact holding, the hatchery having delivered the turkeys, was identified. That holding has been tested for Newcastle Disease, with negative results.
"The most likely source of infection is considered to be transmission from wild migratory birds, which are abundant in the area."
Vaccination against Newcastle Disease is prohibited in Finland.
An outbreak of Newcastle Disease, the first in the country since July 2002, has also been reported in Venezuela. The outbreak affected a sparrowhawk in zoo and fighting cock.
And control measures imposed followed an outbreak of Newcastle Disease in Turkey earlier in the year has now been lifted.
Dr Nihat Pakdil, General Director of Protection and Control, Ministry of Agriculture and Rural Affairs, Ankara, said that the infection had originated from wild birds.
"The disease did not spread from the affected farm. There are no flocks under suspicion of infection in the area or in any other part of the country."
He said that the measures taken in the outbreak area were lifted as of July 19, 2004.
"Cleaning and disinfection were strictly applied again," he said. "Intensive training was given to all the persons involved."