A strong suspicion of bluetongue (BT) was reported on 16 July 2000 in four farms located in the wilaya of El-Tarf, in the communes of Bouhadjar, Zitouna, Bougous and El-Tarf bordering Tunisia.
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The disease was clinically diagnosed after the start of active disease search by the veterinary services of the wilayat along the border strip with Tunisia. Another outbreak was reported a day later in the wilaya of Skikda, in the commune of Baccouch Lakhdar in four neighbouring farms.
The World Reference Laboratory (Pirbright) has confirmed the diagnosis and serotype 2 was incriminated, as in Tunisia.
A crisis cell was established at the central and local levels to monitor the evolution of the situation. An early warning appeal was launched using mass media and explaining the preventive measures to be taken to stop the expansion of the disease.
As of August 2000, outbreaks have been declared in the wilayat of El-Tarf, Skikda, Annaba, Souk-Ahras, Guelma and Tebessa, in the extreme eastern part of the country.
The first outbreaks reported in El-Tarf were located in the commune of Bouhadjar about 300 m from the border with Tunisia. Disease search along the border strip has detected other outbreaks in the same wilaya, as well as in the wilaya of Souk-Ahras at Ouled Moumen, Haddada and Sidi Fredj and in the wilaya of Tebessa in the communes of Ouenza and Lahouidjbet (bordering Tunisia).
According to the information collected in the field, the affected flocks were sharing the same grazing areas with Tunisian flocks. It is interesting to note that a week before the date of the first reported outbreaks, a strong wind was blowing from Tunisia for several days. This may have been responsible for transporting infected vectors. Other cases were reported later in the wilayat of Guelma and Annaba.
It is important to note that the hygrometry and the temperatures prevailing during this season favour arthropod vector development.
Two weeks after the declaration of the first two bluetongue outbreaks of El-Tarf and Skikda, additional outbreaks were reported in four neighbouring wilayat. At the time of writing this report, the situation is stable and the pathology has not reached other wilayat. The average morbidity rate is less than 10 percent and the mortality rate does not exceed 1.6 percent, and is constantly decreasing. An isolated outbreak, unrelated to the other outbreaks, was declared in Tebessa, bordering Tunisia, which strengthens the hypothesis of an introduction of the disease from Tunisia.
The disease affected adult animals only and no mortality was observed in young animals. There has been no apparent impact on pregnant ewes. The majority of affected animals recovered two weeks after the start of the disease and no muscular emaciation or other effects were seen after recovery. The latest outbreak observed was on 5 August 2000 in the wilaya of Tebessa in the commune of Lahouidjbet.
As of 13 August 2000, a total of 24 outbreaks were declared.
As soon as the first outbreaks of bluetongue were declared, mass media were used to sensitize breeders and farmers about the disease and to inform them of the preventive measures to be taken to protect their livestock. Local organizations and phytosanitary services made available the necessary means for disinsectization. As soon as a first case is observed, the whole flock is systematically isolated.
An anti-vectors control plan was set up and directed to the border. The logistics consist of 100 four-wheel-drive vehicles equipped with spray appliances as well as 73 technicians. The disinsectization plan will continue until the autumn; further continuation will depend on the evolution of the weather conditions.
It is worth noting that this operation may fail in the absence of information from Tunisia and owing to the sparse knowledge concerning the evolution of the disease since its first declaration in January 2000.
A serosurveillance scheme for bovines will be launched shortly to find out whether the disease has any impact on this species.
(This report was submitted by the Algerian Veterinary Services to RADISCON Coordinating Unit.)
The main objective of the meeting was to evaluate the results of the sheep pox vaccination campaigns for the year 2000 in Algeria, the Libyan Arab Jamahiriya, Morocco and Tunisia, as stipulated in the agreed working plan. The meeting was attended by veterinary officers responsible for the vaccination campaign in the four countries. The results obtained in implementing the sheep pox eradication programme can be summarized as follows:
In Algeria, the vaccination coverage has significantly increased to reach seven million ovine vaccinated head against 4.5 million in 1998. Despite the fact that the vaccination coverage has not yet reached the agreed 70 percent, it is important to point out the major efforts being made to vaccinate the greatest number of animals, taking into consideration the immensity of the territory to be covered. Since the vaccine in use gives protection for a long period, the proportion of immunized animals would be superior to the number of vaccinated animals, as indicated by the limited number of clinical cases observed (1 to 3 percent) by outbreak. The central-eastern part of the country (comprising the wilayat of Biskra, M'Sila, Djelfa, Tebessa and Saida) is identified as the most-affected area and the majority of the 23 observed outbreaks were reported in these zones. Additional efforts will concentrate on this region.
No figures were available on the sheep pox situation and on vaccination results for the Libyan Arab Jamahiriya because of the administrative restructuring that has recently taken place in the country.
In Morocco, no sheep pox outbreaks have been reported since 1998. The vaccination coverage has reached 90 percent of the four million ovine head in the seven eastern provinces of the country (Oujda, Nador, Taza, Boulemane, Figuig, Errachidia and Ouarzazate). This vaccinated zone serves as a buffer zone. An active surveillance system was put in place throughout the country, consisting of regular visits to animal markets, around water points, flocks, abattoirs, border checkpoints and veterinary clinics. A total of 5 000 800 ovine were examined from June 1999 to May 2000, which represents a monthly prospecting rate of 3 percent of the national total. Three suspected cases were reported and confirmed as being contagious ecthyma. Morocco is willing in the future to involve the private sector in the surveillance of transboundary diseases, through remuneration.
In Tunisia, 2000 was the first year that a vaccination campaign has taken place countrywide. Previously, the decision whether to vaccinate against sheep pox or not was made by the Regional Veterinary Services. A Ministerial Note was sent all around the country requesting the different partners to combine their efforts in order to achieve the desired objective of eradicating the disease. Vaccination coverage has increased from the 1999 level of 40 percent to reach 60 percent in 2000.
In conclusion, with the exception of the Libyan Arab Jamahiriya where more commitment should be shown to attain the objective of the sheep pox eradication programme, all the countries are on a good track towards eradicating the disease by 2005.
The meeting urged FAO and IFAD to implement a follow-up phase of the RADISCON project.
Sheep pox is the major ovine pathology in Algeria. The high concentration of flocks, with frequent animal contacts in stubble fields, around water points and during transhumance movements, combined with insufficient vaccination coverage, have helped maintain the disease. Despite the significant decrease in the number of reported outbreaks since 1996, sheep pox continues to be reported in certain regions of the country.
Ovine livestock mass vaccination against sheep pox has been practised in Algeria for several years. The relaxation in sheep pox vaccination between 1990 and 1993 following the foot-and-mouth disease epizootic explains the increase of sheep pox outbreaks in 1993 and 1994.
The increased vaccination coverage that started in 1994, combined with the change of the vaccination period to coincide with the transhumance season (March to July), has resulted in a noticeable decrease in sheep pox outbreaks recorded since 1995.
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| Number of vaccinated animals between 1990 and 1999 | Number of sheep pox outbreaks reported in Algeria between 1990 and 1999 |
(This paper was submitted by the Epidemiology Unit of the Algerian National Animal Disease Surveillance System. The outputs were produced using TADinfo-Algeria.)
