1.2 Outline of official arrangements
2.2 Epidemiological situation in Mozambique
The first mortalities in what turned out to be the most devastating outbreak of African swine fever (ASF) ever recorded in southern Africa, occurred in March 1994 among pigs housed at the Veterinary Faculty of the Eduardo Mondlane University in Maputo. Within 18 months, and incorporating several waves of infection, the disease had killed at least 80% of domestic pigs in Maputo province (about 40 000 animals), resulting in the collapse of the commercial swine industry which was centred there and unquantified losses to owners of pigs among the "family sector". Losses to pig owners in Gaza and Inhambane provinces also occurred, but at lower rates. This outbreak was the first time ASF had been diagnosed south of the Save River in Mozambique, and the Government requested technical assistance from FAO to control this outbreak and ensure that it did not recur.
This assistance was approved by FAO in June 1995 under the Technical Cooperation Programme project TCP/MOZ/4553, Control of African Swine Fever, and a budget of $US 212 500 was made available. The project, originally estimated to begin in July 1995 and end in February 1997, actually commenced in September 1995 and ended in August 1997. The Ministry of Agriculture was designated the government agency responsible for project execution. Eight visits were carried out to Maputo by five international consultants, and a local consultant, as well as the directors of both the National Directorate of Livestock (DINAP) and the Animal Health Department (AHD) assisted the international consultants in the execution of the programme.
There have been no confirmed cases of ASF in southern Mozambique since August 1996, although the disease was diagnosed in Manica province in June and July 1997. However, since surveillance has not been effectively conducted in Maputo, Gaza and Inhambane provinces since the end of 1996, there is no certainty that ASF is no longer present in southern Mozambique.
The surveillance programme put in place between November 1995 and the end of 1996 established the extent and effects of the outbreak and also extended the available information on the size of the pig population in Maputo province prior to the outbreak. The location of large, medium and small-scale pig producers, as well as the number of pigs originally held by the owners, was recorded on a 1:250 000 map located in the provincial office of the Maputo Animal Health Department. It was impossible to obtain the precise location or establish accurately the numbers of pigs originally held by the family sector in Maputo province, but it is clear that the outbreak almost annihilated the pigs belonging to those people. With the resources available to this project it was not possible to obtain detailed information on pig numbers and the effects of the outbreak in Gaza and Inhambane provinces. However, there are census figures of unknown reliability for all the provinces in Mozambique in the possession of DINAP.
Restriction fragment-length polymorphism (RFLP) analysis conducted at the Institute for Animal Health at Pirbright (the UK) on eight representative isolates of ASF virus collected in Mozambique between March and December 1994 showed that all belonged to the same genotype. This analysis, conducted on behalf of and financed by this project, indicates that all the ASF cases which occurred in Maputo, Inhambane, Manica and Sofala provinces during 1994 were related but different from ASF viruses in Malawi and eastern Zambia. Furthermore, in vivo studies conducted at the Onderstepoort Institute for Exotic Diseases (OIED) support the contention that these viruses are pig-adapted on the basis of their extreme virulence for domestic pigs (S. Swanepoel, 1997 - unpublished data). It is concluded on the basis of these studies that the 1994 outbreak in Maputo, Gaza and Inhambane provinces was the result of a single virus introduction from the north of the country where there is good circumstantial reason to believe that ASF is endemic in village pigs (Plowright et al., 1994).
Although there is a good understanding of how the outbreak arose and spread, the situation with respect to ASF north of the Save River in Mozambique, particularly in Tete province, where the disease is possibly endemic in indigenous pigs, is much less clear. It is vital for the effective future control of ASF in Mozambique that a good understanding of the epidemiology of the disease in the north of the country be obtained, but this was outside the resources of the TCP project.
Prior to the ASF outbreak in March 1994, the diagnostic capacity with respect to this disease in Mozambique was limited and laboratory confirmation of the outbreak was done outside the country. However, effective and efficient laboratory diagnosis of ASF is relatively complicated and this situation prevails in most African countries; it was therefore not in itself an indictment against the abilities of the virus laboratory within the Central Veterinary Laboratory (INIVE).
In order to equip INIVE to handle the present and future ASF outbreaks as well as to maintain effective surveillance, it was decided to concentrate on optimizing the existing direct fluorescent antibody (FA) test for detection of ASF viral antigens in tissues from acutely infected animals and an indirect enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to ASF virus in the sera of pigs. To achieve this, the two persons working in the virus laboratory were trained at the OIED for a period of one week, as well as during two of the international consultancies. Equipment, in particular a plate washer and -20_C freezer as well as reagents, were supplied for both types of assay. Other equipment in the laboratory was checked or serviced, e.g., the fluorescence microscope and -70_C freezer (the latter unfortunately still does not work properly).
ELISAs conducted at INIVE were repeated at the OIED to determine their reliability. A major problem encountered with the ELISA was the high pH of water at INIVE supplied from a bore hole. Eventually this was solved by provision to INIVE of a water purification plant by the African Development Bank. These activities resulted in both the direct FA test and indirect ELISA being pronounced reliable by the international consultant in April 1996. During the consultant's final visit in July 1997 he was informed that reagents for both the direct FA and indirect ELISA were in short supply. Also, the plate washer taken by him to Pretoria for repair at the end of his previous visit was returned to INIVE without the power cable and instruction manual and was therefore not operational. This and the still defective -70_C freezer were a constraint to proper diagnosis and surveillance.
Although the personnel of the virology laboratory was adequate in a technical sense, leadership, initiative and drive were found to be lacking. The possible consequence therefore is that the capacity of INIVE with respect to ASF will revert to the situation that prevailed in 1994. The lack of committed and able personnel in the virus laboratory is the major constraint to efficient ASF diagnosis as well as surveillance in Mozambique.
The control of any epidemic disease is dependent, among other things, on surveillance which is able to detect and monitor transmission. For this reason, one of the primary aims of the project was to help establish an effective surveillance system in southern Mozambique. Prerequisites in this respect are the regular inspection of pigs, rapid reporting of disease by farmers, and serological monitoring so as to detect non-lethal infection and possible carriers. Practical constraints make it difficult for the AHD to visit pig farms on a regular basis and it was therefore decided that effective surveillance would best be achieved by post-mortem inspection and serum collection by meat inspectors in the employ of the AHD at commercial abattoirs. Arrangements were made for this to be done between the AHD, INIVE and abattoirs in Maputo (Bon Suino, belonging to a farmers' cooperative) and at Beira. This produced useful information up to the end of 1996 but presently it appears that the programme has come to a halt. This means that active monitoring for the presence of ASF has ceased. For this reason it is not certain whether ASF has now burnt itself out in Maputo province or remains at a low but undetected level.
During his final visit, the consultant was informed by the local consultant of plans he had made to continue the collection of pig sera during his training programme due to commence at the end of July 1997.
For reasons explained in detail in previous reports, ASF in Mozambique is not presently actively controlled. Essentially, there is a lack of resources with which DINAP and the AHD could achieve anything meaningful in present circumstances. A proposal as to how the long-term re-establishment of commercial pig farming in southern Mozambique could be approached, bearing local circumstances in mind, has been made. This includes a restocking programme, training of farmers in on-farm control of highly contagious diseases, infrastructural improvements on pig farms, access to affordable credit and changes to legislation on the control of ASF. The exercise would demand a separate project of considerable financial and logistical proportion, but is possible bearing in mind the FAO/Government Cooperative Programme for Assistance to the Livestock Restocking Programme of Mozambique (recently submitted to the European Union), as well as other restocking initiatives.
A further proposal to address the problems of the family sector, which takes account of the fundamental problem of free-ranging pigs, has also been presented. The approach suggested involves providing family-sector producers with strains or breeds of pigs resistant to ASF. This, however, requires basic research that would take some years to conclude but, on the other hand, would also provide a solution for many other countries in Africa which face the same problem as Mozambique.
The following training opportunities were provided by the project:
- two laboratory personnel were trained in ASF serology during a week-long visit to the OIED in Pretoria;
- the same two persons received in-service training during two of the international consultancies;
- a two-day course was provided for field technicians in Maputo, Gaza, Inhambane, Sofala and Manica provinces in December 1996.
In addition, the national consultant provided training for veterinarians in Tete, Nampula and Zambesia provinces, and for agricultural extension workers in Maputo, Gaza and Inhambane provinces.
Provision was also made for the compilation of a 5 to 10-page training booklet to be prepared by a staff member of the Veterinary Faculty (Eduardo Mondlane University, Maputo), and for the production of posters concerning ASF for an awareness campaign.
As a result of this project, there are two proposals for re-establishing pig husbandry in southern Mozambique, one for the commercial and the other for the family sector. However, since both proposals imply projects requiring considerable expense as well as technical input, it is most unlikely that they can be achieved by Mozambique alone. On the other hand, there are a number of other countries in southern, central, eastern and western Africa that are confronted by the same problems related to ASF which are unique to sub-Saharan Africa. There is therefore good reason for these countries to cooperate in finding a solution, ideally in association with international agencies able to assist. As a first step, DINAP should consider initiating a discussion with other African countries experiencing similar difficulties and involving international donors and others with the potential to assist in ASF control.
DINAP should accept that, unless there is urgent provision of competent leadership within the virus laboratory at INIVE, the diagnostic and surveillance capacity that the project sought to establish cannot be maintained. This also applies to other important viral diseases such as Newcastle disease and rabies.
The training still outstanding should be completed, including the drafting of a booklet on ASF for field workers; whoever does this should obtain the assistance of the project's national consultant. The need for and objective of the envisaged poster on ASF needs to be carefully considered, as the outbreak appears to have come to an end.
Research into how ASF behaves in the north of Mozambique, particularly in Tete province, is essential to the long-term control of ASF. Since countries on the borders of Mozambique are similarly afflicted, the Government should consider initiating collaborative projects with countries such as Malawi, Zambia and the Congo.
Equipment and reagents for ASF diagnosis and surveillance that are in short supply or not operational should be repaired or provided by funds still available through this project. The OIED in South Africa is able to continue to help in this respect. In the longer term some arrangement should be reached with an international reference laboratory ideally involving a range of strategically important animal diseases.
Report on the consultancy 15-27 October 1995. G.R. Thomson, 3 November 1995.
Report on the consultancy 16 and 17 November 1995. G.R. Thomson, 29 November 1995.
Report on the consultancy 4 March - 4 April 1996. I.D. Gumm, 12 April 1996.
Report on the consultancy 27 March to 3 April 1996. G.R. Thomson, 15 April 1996.
Report on the consultancy 9-19 April 1996. S.P. Swanepoel, 26 April 1996.
Report on the consultancy 7-9 August 1996. G.R. Thomson, 23 August 1996.
Report on the consultancy (training) 9 - 19 December 1996. F. Boinas, January 1997.
Report of 2 January 1997. G.R. Thomson.
Selection of pigs resistant to ASF. G.R. Thomson.
Report on the consultancy (training) 28 July - 30 September 1997. A. Mavale, 30 September 1997.
