So far, analysed data show that 8 511 pigs have died out of 10 291 cases in 38 foci of infection. These foci of infection are found throughout the country, with the exception of Lower River Division that has no record of an outbreak.
Current situation in the Gambia
In March 2000, the Department of Livestock Services in the Gambia reported outbreaks of African swine fever (ASF) in Greater Banjul area and Western Division. The epidemic spread to North Bank in April/May and, by June 2000, ASF outbreaks were being reported in Lower and Upper River Divisions.
In June 2000, FAO approved a project entitled "Emergency eradication of African swine fever and enhancement of logistical and technical capacities of the Department of Livestock Services" (TCP/GAM/0065) to assist the Government of the Gambia contain the further spread of this epidemic.
The activities of the project, which are in different stages of implementation, mainly concern staff training, enhancing the technical and logistic capacities of the Department of Livestock Services, developing the disease reporting, surveillance and monitoring system to a good level and efficient database management for ASF. There will be a programme of sensitization and education of pig farmers in the country and other stakeholders in the pig industry on the disease in order to establish an early warning/early reaction system.
The current status of ASF
A three-week nationwide epidemiological survey and pig census was carried out between 11 and 29 November 2000. The aim of the exercise was to define the foci of infections and determine the number of pigs in the country.
Data entry is under way using TADInfo, and it is expected that over 2 000 records will be entered following the survey. A preliminary analysis of the data already entered has shown a definite pattern of spread, which is consistent with the information collected during workshops and field visits.
To date, analysed data show that 8 511 pigs have died out of 10 291 cases in 38 foci of infection. These foci of infection are found throughout the country, with the exception of Lower River Division that has no record of an outbreak.
The Greater Banjul area recorded the highest mortality, with 4 063 pigs dying out of 4 666 cases in eight foci of infection. Upper River Division was least affected, with eight mortalities out of 25 cases in only one focus of infection.
By month, March and August witnessed the highest numbers of cases with 2 392 and 2 628 cases respectively. However, April recorded the highest number of foci of infection, with nine different foci erupting in the month. In November 2000, only one focus of infection was recorded.
This survey has covered over 2 000 pig units. The map shows the ASF status as of November 2000.
ASF outbreaks in Gambia
Current situation in Ghana
ASF was recorded for the first time in Ghana in September 1999. The outbreaks occurred in Greater Accra Region and parts of the Volta Region. Stamping out measures were instituted to eradicate the infection, followed by intensified surveillance activities and a "sentinelization" process that came to an end in September 2000. In October 2000, the Government declared freedom from ASF disease and infection and lifted the ban that had been imposed. The pig populations in the affected areas are Greater Accra Region (20 000 pigs), Central Region (16 000 pigs) and Volta Region (47 000 pigs). During the outbreak, about 600 pigs were lost and 6 927 were slaughtered with compensation awarded to the owners. Ghana has an estimated pig population of about 350 000.
The stamping out exercise in Ghana
PHOTO COURTESY OF D. NYAKAHUMA, EMPRES
ASF outbreak
Although neighbouring Côte d'Ivoire and Togo experienced successive outbreaks of ASF in 1996 and 1997 respectively, Ghana remained free from the disease until October 1999. Faced with such a threatening situation with two of the country's neighbours, Ghanaian veterinary authorities took steps to avert the introduction of ASF into the country. They thus made a considerable investment in training field staff and raising public awareness. Strict border controls were instituted, and massive public sensitization campaigns were mounted through media and workshops about the dangers of the introduction of ASF from neighbouring countries. These and other activities were carried out under the FAO/TCP project on "Enhancing prevention capacities for emergency intervention against African swine fever in West Africa" (TCP/RAF/7822). In addition, the enhanced early warning capacity of the veterinary services achieved under this project enabled timely detection of the present ASF outbreak in Ghana. The outbreak, the first in the history of the country, prompted the Government to seek external assistance to combat the emergency. In response, FAO contributed US$306 000 through a subsequent project entitled "Emergency assistance to eradicate African swine fever from Ghana" (TCP/GHA/8925).
Vehicle disinfection during stamping out exercise
PHOTO COURTESY OF D. NYAKAHUMA, EMPRES
The World Bank also responded positively and made funds available (US$300 000) from the National Livestock Services Project. These funds greatly complemented the resources under the present TCP project as they served as a compensation fund for farmers whose pigs were destroyed under the stamping out order. This policy entailed the destruction of all animals on affected premises, including slaughter of free-range village pigs in and around affected areas. Farmers were paid at a cost price of ¢3 000/kg live weight (US$1=Cedis ¢3 000). These and other stringent measures on animal movements were essential for ASF to be eradicated from the country.
Sentinel pigs for ASF in Ghana
PHOTO COURTESY OF D.NYAKAHUMA
"Sentinelization" phase
At the beginning of the "sentinelization" period, ASF-free farms were identified. Sentinel pigs were identified, tested, purchased and deployed.
For this exercise, 200 pigs were purchased, deployed in 20 groups (ten pigs per group) in locations that had previously experienced ASF outbreaks. After a period of six weeks, serum was collected and tested using an ELISA ASF antibody test. All the pigs purchased were still alive at the end of the sentinelization phase.
Because of the ban on pig movement throughout the country, the pigs were enclosed in pigsties; leaving them to roam would have given the impression that the pig ban had been lifted.
Epidemio-surveillance
Following the stamping out, mopping-up operations, training workshops and public awareness campaigns, there was no restocking whatsoever in the affected area. Local communities destroyed residual pigs that had fled to the bush. The state of complete depopulation has remained in place from December 1999, and no clandestine movements have occurred. Rumours of pork and pork products that were reportedly brought into the country were promptly and fully investigated. In the other unaffected regions, reports of suspicious pig illnesses and/or deaths were fully investigated.
Public sensitization activities
The continuation of public sensitization activities is necessary following the verification of freedom from ASF and infection. This will ultimately be followed by the lifting of the ban on movement of pigs and pig products that is currently in place.
Partial lifting of the ban
In January 2000, after the slaughter exercise, two active foci were reported. These were investigated fully and stamped out. To relieve pressure from producers in ASF-free areas (created by growth in their stock resulting from the ban that had been in place for four months), a partial ban was instituted at the end of January 2000. This allowed sale of stock under the full supervision of the veterinary services. With this controlled slaughter policy, pork processors bought pigs from farms approved by the veterinary services, which were then slaughtered only at the Accra abattoir. This eased the pressure from producers who were making losses as a result of high costs of overstocking, and gave them an opportunity to offset their running costs.
Restocking
In order to maintain vigilance on surveillance, the veterinary staff is fully involved in the process of restocking. The purpose is to guide those interested in restocking on suitable sources that are known to be ASF-free. This will also give the veterinary staff a picture of the movements of pigs and throw light on areas of intensified monitoring activities.
The lessons from Ghana
The eradication of ASF in Ghana demonstrated that a strong and committed veterinary service is the key to competent, rapid utilization and mobilization of international assistance and cooperation programmes. There are challenges ahead in keeping ASF out of Ghana. With the lessons from the past epidemic, Ghana fully appreciates the importance of around-the-clock epidemio-vigilance and prompt follow-up investigations and action in the case of reports of suspicious cases.