Field evaluation of a dog owner, participation-based, bait delivery system for the oral immunization of dogs against rabies in Tunisia.

We evaluated a dog owner, participation-based, bait delivery system for the oral immunization of dogs against rabies. In a field study in a semirural area of northern Tunisia, dog owners were asked to come to temporary bait delivery sites. A total of 314 baits were given to 178 dog owners in four sites. The experimental baits used consisted of a freeze-dried core unit containing sulfadimethoxine (SDM) as a biological marker and an aromatized paraffin envelope. No vaccine was used. Preliminary tests had shown that by using a rapid commercial card test, positive SDM serum levels were detected in more than 95% of dogs up to two days after bait ingestion. During the two days following bait delivery, we visited more than 95% of all households in the study area and took blood samples from as many owned dogs as possible. Unconsumed baits were recovered and human contacts with the bait matrix were recorded. The campaign required 7.6 person-min per bait and 13.5 person-min per dog owner for providing baits, gloves, and instructions. The estimated average cost effectiveness ratio per dog accepting a bait was 1.7 US dollars. From the indications given by the dog owners and the results of the SDM test, it was concluded that 85-90% of the owned dogs in the study area had consumed a bait at least partially. Of 314 baits delivered, 78.7% were fully consumed by dogs and 4.1% were recovered during the household survey. The remaining baits (17.2%) that were not recovered were either not consumed or only partially consumed by the target dogs (3.7 baits per 100 inhabitants). These baits probably remained within the highly populated areas and were potentially accessible to other domestic animals and other nontarget species, including humans. Twenty-five unprotected human contacts with baits were recorded (1.7% of all inhabitants). Our study has demonstrated the potential of dog owner based bait delivery. This technique is simple and efficient, particularly if the human population is accustomed to mass immunization in defined centers. Before applying this method on a large scale with live vaccine loaded baits, further studies should focus on minimizing the number of human contacts with the vaccine bait, systematizing contact identification and establishing structures in ensuring proper treatment if exposure to vaccine should occur.

[The 1996 epizootic of African swine fever in the Ivory Coast]. / L'épizootie de peste porcine africaine de 1996 en Côte d'Ivoire.

African swine fever was reported for the first time in the Côte d'Ivoire on 16 April 1996, in Abidjan. The epizootic resulted in the death of 135,000 pigs, equivalent to 29% of the pig population, of which 80% came from the commercial sector. By November, the outbreaks had stabilised and were then eliminated. All epidemiological evidence showed that the active form of disease ceased in September 1996. A variety of factors were responsible for limiting and then halting progression of the disease from the end of August 1996, including a new strategy which gave priority to local information, better control of the situation, depopulation of the infected area in Abidjan, the epidemiological containment of most cases within the villages, and also the assistance and direct involvement of the Food and Agriculture Organization (FAO) of the United Nations. The contribution of the FAO was decisive. It provided a diagnosis of the situation, recommended emergency measures, developed a control strategy, ensured the implementation of the control programme, set up a diagnostic laboratory unit and provided training for staff, slaughtered and destroyed any remaining pigs, set up and implemented a local information programme, developed and implemented a scheme for sentinel animals and for epidemiological surveillance, and designed, performed and analysed an epidemiological survey. From the commencement of the epizootic, two major shortcomings became apparent: inadequate dissemination of information, and a shortage of technical resources allocated for the control of African swine fever. These two shortcomings were compounded by other technical and socio-economic constraints.