The tenth PAAT Advisory Group (PAG) Coordinators’ meeting was held at the FAO Regional Office for Africa (FAORAF), Accra, Ghana, 22 - 23 September 2004. The meeting was jointly organized by FAO HQ, Rome and FAORAF, and supported by the Food and Agriculture Organization of the United Nations, the Inter-African Bureau for Animal Resources of the African Union, the International Atomic Energy Agency and World Health Organization of the United Nations.
Prof. Albert Ilemobade, Chairman of PAAT, made the introductory remarks, followed by a welcoming statement from Mr Mensah Agyen-Frimpong, Director of Ghana Veterinary Services. Mr Joseph Tchicaya, Assistant Director General/Regional Representative for Africa of FAO officially opened the meeting.
Conclusions and recommendations
1. Conclusion: The meeting commended the ADB-PATTEC initiative aimed at financing (through ADB loans and grants) multi-national tsetse and trypanosomiasis (T&T) intervention projects in East (Ethiopia, Kenya and Uganda) and West Africa (Burkina Faso, Ghana and Mali). The PAG appreciated this development and the role of Ghana in bringing together countries concerned to hold the project appraisal workshop in Accra.
Recommendation: The meeting:
Urges recipient countries to take advantage of available expertise in PAAT for project implementation, monitoring and evaluation;
Encourages other governments and their national institutions to show similar levels of commitment to T&T intervention;
Urges the strengthening of collaboration between PAAT and PATTEC in bringing about the achievement of the stated goals of the project.
Action: ADB beneficiary countries, PAAT and PATTEC.
2. Conclusion: The meeting observed with concern the inability of the FAO Liaison Officers (LO) to perform as required and the dwindling frequency of their meetings. The meeting considers that the LOs play a key role in feeding PAG with information necessary to its work.
Recommendation: It is recommended to:
Re-activate as a matter of urgency the activities of the FAO LOs;
Ensure that terms of reference of the LOs are clear and updated;
National Governments to provide the LOs with resources to carry out their tasks.
Action: FAO Regional Office for Africa.
3. Conclusion: The meeting noted with appreciation the progress that has been made in the search for new drugs for the treatment of sleeping sickness. The WHO initiative of bridging the gap between research and control by the establishment of the HATNETWORK is also acknowledged. This network should facilitate the development of new drugs and the use of new tools.
Recommendation: The meeting recommends:
To continue to support work on the development of new drugs and new diagnostic tools which can be considered as key elements needed to achieve disease elimination;
To form a task force to facilitate and support the implementation of clinical trials for new drugs and the application of new diagnostic tools;
To support the development of sub-regional disease elimination programmes.
Action: WHO.
4. Conclusion: The meeting recognised the importance of advocacy as a means of accessing resources for the support of T&T interventions and observed that there has been an improvement in the communication between T&T workers and policy makers.
Recommendation: The meeting:
Urges increasing cooperation and collaboration between policy makers, researchers and field personnel;
Recommends that T&T workers include strong advocacy as a key element of their general strategy and to actively participate in:
(a) decision making on the elaboration of livestock development policies at the national, sub-regional and continental level;
(b) the dissemination of information on T&T, livestock production and rural development;
(c) the sensitisation of livestock farmers’ associations and support to these associations and other livestock professionals at the local, national and sub-regional levels.
Action: National, regional and international policy makers, CVOs, extension and delivery services.
5. Conclusion: The meeting observed with appreciation the diverse ways in which CIRDES and ITC have supported NARS and institutions charged with T&T interventions in the West African region in the area of training. Also, it was noted with concern the lack of well-defined strategic training needs.
Recommendation: The meeting recommends to:
Develop mechanisms that would ensure that T&T endemic countries take full advantage of training opportunities;
Assist NARS and national institutions charged with T&T interventions to identify strategic training needs;
Re-visit PAAT previous recommendations on training needs and where necessary update them in the context of emerging trends.
Action: CIRAD, CIRDES, ITM, ITC, PAAT.
6. Conclusion: The meeting recognises the growing importance of public-private sector partnership in national development and in any intervention in T&T.
Recommendation: The meeting recommends PAAT to explore avenues for fostering such partnership in the future.
Action: PAAT and its stakeholders.
7. Conclusion: The meeting recognises that the commitment of NARS and other national stakeholders is crucial to the success of T&T interventions.
Recommendation: Every effort should be made to stimulate the active participation of NARS and all the stakeholders involved in national and regional T&T intervention programmes.
Action: National governments, NARS, National Extension and Delivery Services.
1. Brief and discussion on the last PAG meeting report - A.A. Ilemobade
The report of the previous meeting held in Pretoria in September 2003 was discussed, and the conclusions and recommendations endorsed. The PAG was informed that the proposal of the "ICPTV - phase two" was not accepted for funding by the European Union, and ITM was exploring other financial sources. Additional information concerned meetings held in 2004 addressing the standardization of methodologies and devices for tsetse trapping and use of insecticide. In this regard, conclusions and consensus have not been reached yet. The participants agreed on the provisional agenda and time table. The next PAG meeting will be convened in Addis Ababa, Ethiopia, in September 2005 in conjunction with the 28th ISCTRC Conference.
2. The problem of T&T and related control: a move into the future and the importance of PATTEC - K. Gyening
Despite a century of efforts, tsetse-transmitted trypanosomiasis still constitutes a major constraint for livestock-agricultural development in sub-Saharan Africa. Main problems in limiting or eliminating the impact of the disease derive from there being only a limited number of drugs available for disease treatment, an increased presence of drug resistant strains of parasites, a reduced capacity of veterinary services in delivering appropriate strategies to farmers for a proper use of chemotherapy, the high cost of vector control campaigns and difficulties in obtaining the involvement and participation of the local communities to support T&T interventions.
Elimination of the T&T problem implies its removal and preventing it from coming back: this is a complex exercise. A fundamental prerequisite is the geographic isolation of the vector population(s) which allows the application of integrated area-wide pest management strategy in combination with proper management of land and other natural resources rendering the habitat unsuitable for reinvasion or new vector colonization. Due to the transboundary nature of tsetse distributions, a regional approach is needed. Training and capacity building also have to be considered in the planning phase of a T&T field intervention.
Now, for the first time in more than 100 years, the African Nations have collectively shown the political will to free the continent from the burden of T&T. This political will was concretised with the endorsement by the OAU (now AU) of the Pan African Tsetse and Trypanosomiasis Eradication Campaign (PATTEC) in 2000.
Currently, ADB has shown interest in supporting T&T interventions through allocation of loans and grants to six tsetse-affected African countries (Burkina Faso, Ethiopia, Ghana, Kenya, Mali and Uganda). Ownership and direct involvement of national governments are necessary to pave the way for success of interventions. In this context, PAAT is likely to provide the ideal environment to establish a mechanism for international collaboration, and neutral, technical advice and assistance in the planning phase. As recommended at the last ISCTRC Executive Committee meeting (Addis Ababa, September 2004), further consultation between PAAT and PATTEC is needed for concerted action with regard to this ADB initiative.
3. Report of the PAAT Secretariat and FAO/PAAT activities - R.C. Mattioli
In the nine million square kilometres of sub-Saharan (SS) Africa infested by tsetse, 55 percent of the rural population lives below the poverty line. The proportion of under-nourished in sub-Saharan Africa has not dramatically changed since the early nineties. A negative relationship exists between the extent of cultivated area and under-nourishment. For instance, in the Near East and North Africa 28 percent of the total land is cultivated with 10 percent of people undernourished, while in sub-Saharan Africa only 3 percent of the land is cultivated and the fraction of the population undernourished reached 33 percent. Vast areas facing the T&T problem are suitable for livestock-agricultural development. Hence, besides the technical feasibility of any T&T intervention, it is necessary to concentrate efforts in those areas offering potential for land development. PAAT’s strategy is to promote SARD with a view to increase food security and reduce poverty in tsetse affected countries, and the role of PAG, the policy and strategy setting body of PAAT, is to develop standardised normative procedures and methodologies for T&T interventions in the context of SARD.
The PAG was informed about FAO and PAAT activities as related to T&T since the 2003 PAG meeting. FAO and PAAT support to member countries and PATTEC was concretised in the endorsement of the FAO Progress Report on the implementation of the PATTEC initiative by the 32nd FAO Conference (Rome, December 2003). The concept note, developed by Ethiopian officials with the assistance of FAO and IAEA, concerning field T&T intervention in the Ethiopian Southern Rift Valley was officially endorsed by the Ethiopian Government. Further actions in the implementation of PAAT-PATTEC agreements concerned the organization of an international workshop on "Strategy for integrated T&T intervention in the ‘cotton-belt’ of Burkina Faso and Mali", held in Ouagadougou, Burkina Faso, February 2004. Representatives of Burkina Faso, Mali, IAEA and FAO attended the forum. A major output of the workshop was the production of a note of interest concerning "Poverty reduction through reinforcement and intensification of mixed farming in T&T intervention area in the cotton-belt zone of Burkina Faso and Mali". The note of interest was presented at the 8th PAAT Programme Committee, held in FAO HQ, April 2004.
Two PAAT Technical and Scientific Series papers were published, a first paper entitled "Economic guidelines for strategic planning of tsetse and trypanosomiasis control in West Africa", and a second one dealing with "Long-term tsetse and trypanosomiasis management options in West Africa". Two additional papers are in press or in progress:
(a) The role of trypanotolerant livestock in the context of trypanosomiasis intervention strategies (expected to be published first half of 2005);
(b) Mapping the benefits of disease removal as a decision tool for T&T intervention (expected to be published jointly by FAO and DFID second half of 2005).
With regard to publications, a joint FAO-IAEA-WHO-ERGO paper was published in the international journal Food, Agriculture and Environment, with the title "Tsetse and trypanosomiasis intervention policies supporting sustainable animal-agricultural development" [see TTI 27(2) 12891]. A radio interview ("Lutte contre la trypanosomose: partir du développement rural") was broadcast by AGFAX-WREN (World radio for the Environment) media in May 2004. A communication on FAO and PAAT activities was presented at the OIE/NTTAT (Non-Tsetse Transmitted Animal Trypanosomiasis) meeting held in Paris, May 2004.
In relation to the involvement of the private sector in FAO and PAAT activities, a first draft of the Memorandum of Understanding between FAO and IFAH on the harmonization of standards and protocols for quality control/quality assurance of trypanocides has been produced and is currently under evaluation by the interested parties.
Through the FAO Representative in Sudan, preliminary contacts were undertaken with the EU for a possible WHO/FAO project on human and animal trypanosomiasis control in south Sudan. Progress was made in securing a grant from IFAD to support the PAAT Information System (PAAT IS). The grant is expected to be available early 2005. Additional financial support was received from CIRAD-EMVT, ITM and DFID mainly as contributions to the publication of the Tsetse and Trypanosomiasis Information (TTI) bulletin (formerly the Tsetse and Trypanosomiasis Information Quarterly). The PAG was briefed on the outcome of the PAAT Programme Committee (PAATPC) meeting, held in FAO Headquarters, Rome, April 2004. The meeting was attended by representatives of Burkina Faso, Ethiopia, Kenya, Mali, Namibia, AU/IBAR, IAEA, WHO, international research institutes, an FAO-NEPAD related officer, and representatives of the donor community (e.g. ADB, IFAD, Italian Cooperation, USDA/APHIS) and private sector (e.g. IFAH). The meeting focused on (i) progress and achievements of the four PAAT mandated organizations (AU/IBAR, FAO, IAEA, WHO), (ii) advancement in the preparation of conceptual notes for field programme proposals for T&T interventions in the two PAAT-PATTEC agreed priority areas, (iii) economics of T&T intervention, and (iv) the role of the private sector in intervention activities. The report is expected to be available early 2005 and will be distributed through PAAT-Link and will be downloadable from the PAAT website.
Future FAO/PAAT activities will concentrate on (i) the advancement of the PAAT-PATTEC harmonization process, (ii) refinement and promotion of common policies for T&T interventions aiming at a positive SARD, (iii) assisting African countries (e.g. those countries receiving ADB support for T&T intervention) in planning SARD related T&T intervention programmes, (iv) implementation of FAO-IFAH partnership on quality control of trypanocides.
The PAG was informed about the venue of the next PAAT-PC meeting (IAEA Headquarters, Vienna, 3-4 May 2005) and PAG meeting (Addis Ababa, just prior to the ISCTRC meeting, September 2005).
The discussion which followed the presentation drew members’ attention to the inactivity of the FAO Liaison Officers’ (LO) platform. Concern was expressed about the irregularity of the LO meetings. The FAO Regional Office for Africa was urged to re-establish the LO meetings on a regular basis to provide the necessary support for PAG decisions. Some PAG members reported on the inability of the LO to perform efficiently because of logistic constraints. The PAG expressed agreement on the need for training, essential in the preparation for the implementation of field T&T intervention activities. In this regard, the meeting agreed that there is a general concern about a vacuum being created at the middle level category/personnel due to the retirement (and ageing) of most of those who were trained in the seventies and eighties. The open door policy of CIRDES and ITC to the training needs of countries in the West African region was commended.
4. Report of AU/IBAR activities - J. Musiime
The AU/IBAR report focused on implementation and achievements of the FITCA project, which is now operative in five East African countries: Ethiopia, Kenya, Rwanda, Tanzania and Uganda. The overall objective aims at the improvement of the welfare of people through sustainable rural development. A major specific objective concerns increased livestock-agricultural productivity by improving animal health through T&T control and integration of crop-livestock production with a view to increase level of food security. A key element of the FITCA project is the promotion of partnerships between local communities, public and private sectors and NGOs. In this regard, local communities are the primary agents in supporting tsetse control activities. Village communities are mainly active in the deployment and management of insecticide impregnated targets. In addition, farmers’ communities (more than 600 farmers’ groups established in Kenya and Uganda) engage in building and managing "crush pens" where cattle are treated epicutaneously with insecticides (upon payment up to KShs20), dewormed and receive additional health treatments. In fact, "crush pens" are now used as Rural Animal Health Centres by the village communities assisted by private animal health providers.
Work carried out by FITCA has shown that tsetse control and rural development are interdependent. On the one hand, without controlling flies farming cannot become more productive; on the other hand, improvement of the rural infrastructure is hampered where agriculture is unproductive due to the presence of trypanosomiasis. Where the trypanosomiasis constraints were removed (i.e. in certain project areas in Kenya, Uganda, Ethiopia and Tanzania) or tsetse fly controlled, integrated crop-livestock farming systems were established.
The introduction of insecticide-treated netting in Kenya, Uganda and Tanzania appears effective in protecting zero-grazing cattle production units not only from tsetse flies, but also from other nuisance biting insects, including mosquitoes. The demand for impregnated nettings is increasing and AU/IBAR is assisting in acquiring official registration of the netting technique for its easy availability on the market in Kenya and Uganda. Cases of sleeping sickness have been dramatically reduced in project areas in Kenya and Uganda. In the latter country, medical teams are fully operational in 12 districts and several "sleeping sickness hospitals" have been renovated in Uganda. A monitoring, surveillance, diagnosis and treatment scheme has been established and free treatments have been made available through WHO/private sector (AVENTIS) co-operation.
In the project area, the Environment Management and Monitoring Component (EMMC) of FITCA is implemented through a special agreement with ILRI and the Scientific Environment Monitoring Group. A baseline survey on the environment has been carried out in Kenya, Uganda and Ethiopia using remote satellite imagery backed by ground-truthing in 3 - 4 selected villages of 5 km2 in each study area. The field survey assessed natural vegetation and biodiversity, current land use and, where possible, land use changes over time. This information is complemented with socio-economic surveys. FITCA financed research activities involving several national (KETRI, Kenya; LIRI, Uganda) and international (ILRI, ICIPE) institutions. The total amount of research fund allocated was €200 000.
Finally, the presenter informed the house that the next ISCTRC Conference will be held 26th September - 1st October 2005, in Addis Ababa, Ethiopia.
5. Report from IAEA - U. Feldmann (based on a note sent to the PAAT Secretariat)
Since the last PAG meeting (September 2003, Pretoria, South Africa), the IAEA’s tsetse activities underwent a major internal and external review evaluation. While the findings and conclusions are not available at this stage, it is likely that the evaluation will have implications for the future interaction of the Agency with member states and other partners and stakeholders in the field of tsetse and trypanosomiasis.
The Agency’s objective is to promote the use of nuclear techniques in the context of sustainable development. Although disputed by some, the sterile insect technique (SIT) is generally recognised as a proven technique when applied within an area-wide integrated pest management (AW-IPM) strategy. As such, the SIT component has the potential to contribute to the removal of the T&T problem in some selected development areas in African member states. The Agency’s mandate and specific expertise and experience lie with the transfer of SIT in support of this goal. Therefore, its support activities will, in the future, be largely restricted to the SIT component of AW-IPM. Other activities that were previously also supported by IAEA, such as conventional suppression activities using insecticides on livestock or artificial baits prior to the SIT phase, will, in future, likely need to be conducted by other partners or stakeholders.
The Agency’s assistance to member states efforts against T&T will continue to benefit from its scientific-technical and management expertise. Substantially increased emphasis will be on the principles of national and regional ownership and international harmonization and prioritization. The Agency recognises that attaining the creation of tsetse-free zones will require a concerted action by many partners over many years, including appropriate policy, institutional and technological interventions with substantial human resources and financial commitments. IAEA will, therefore, work with development agencies and other partners to assist its member states in enhancing the effectiveness of their activities by strengthening their human resources and infrastructure and leveraging the financial contributions required to ensure that the full potential of SIT can be realised as a contribution to the wider development goal and in the context of the AU-PATTEC initiative. Further harmonization between PATTEC and PAAT is expected to avoid duplication of efforts by the different international partners and other stakeholders and to provide synergetic inputs to member states in support of the common development objective.
Relevant services to member states will continue to be conducted using both the Agency’s Regular Budget (RB) resources and the IAEA Technical Cooperation Funds (TCF).
RB funds will continue to be used for:
Normative work, including the development of standards, guidelines, manuals, etc.) in close collaboration with other partners and through mechanisms like PAAT;
In-house research at the FAO/IAEA Agriculture and Biotechnology Laboratory, Seibersdorf, Austria;
Coordinated Research Projects (CRPs); and
Consultants’ meetings on relevant topics.
With regard to TCF, the Agency consistently experiences increasing member states’ demand for TC support activities in the field of T&T, and it remains a challenge to secure sufficient resources to meet the demand. In the near future, it is intended to pursue ways of enhancing the impact of TC projects, through better up-front planning, increased monitoring of results and expanded partnerships. In this context, the Agency’s tsetse related activities obviously will reflect and be in line with member states’ national development plans and priorities, and technical assistance to field projects will follow a phased, conditional approach.
After a screening of the national policies, priorities and commitment and an initial phase of baseline data collection, the subsequent phases (feasibility assessment, pre-operational phase and operational phase) would only be supported by the Agency provided pre-agreed conditions/criteria are met. In all phases, the Agency would only contribute to assist in the SIT-relevant component.
With regard to IAEA TCF supported activities in member states, IAEA currently supports SIT-baseline data collection, feasibility assessment and capacity building in ten T&T affected countries through eight national and one regional projects. As SIT is only a component of larger projects for creating tsetse-free zones and for overall sustainable agriculture and rural development, and considering the complex and multidisciplinary nature of such operations, IAEA does not and will not attempt to manage or lead such field programmes in the member states. The Agency’s role is to provide relevant guidance and advice on the establishment of appropriate national/sub-regional management structures for the effective execution of AW-IPM projects with an SIT component. Consistent with the efforts initiated under PAAT-PATTEC harmonization process and the above mentioned phased, conditional approach, the Agency will need to focus on a limited number of operational projects with the potential to create tsetse-free zones, provide capacity building where feasibility study was positive, and continue to support requests for the feasibility studies in other member states as appropriate.
Regarding new member states’ request to IAEA for technical assistance in the field of T&T, the Agency will need to introduce a more rigorous project appraisal process, with attention being paid to the government’s commitment, the assessed technical feasibility, the relevance and anticipated impact of the proposed collaborative efforts in the context of sustainable agriculture and rural development, and the availability of Agency resources (human and financial) to ensure the effective delivery of its input.
6. Report from WHO - J. Jannin
Since the establishment of PAAT, WHO has adapted its strategy to meet PAAT’s overall objectives, namely to provide a networking platform, to collect and disseminate information, to develop policy and strategy and to promote advocacy and awareness. These actions resulted in the establishment of a strong partnership with all those involved in sleeping sickness surveillance and control. These objectives complement the WHO’s mandate for coordination, support and resource mobilization for field activities and research. In practical terms WHO has created a forum where people can not only exchange ideas and share views on the final goal to eliminate sleeping sickness but also propose new activities and approaches to improve sleeping sickness surveillance and control. This forum took the name of the Human African Trypanosomiasis Network and brings together everyone concerned through a networking concept. Within this networking process much progress has taken place and has been regularly reported at the PAAT meetings. Awareness has been considerably raised among the decision makers and the population at risk. With the willingness of public agencies and the private companies, coherent actions could be implemented. It is now conceivable and there is a great hope that elimination of sleeping sickness, as public health problem, will be achievable. The times when some 60 000 cases were diagnosed and treated while only 10 to 15 percent of the population at risk were under some surveillance is over. In the last years there has been a regular decline of cases, and in 2004 the number of new cases was less than 17 000, while there has been a substantial increase in the number of people under surveillance.
The most outstanding achievements were an improvement in diagnostic quality, a substantial increase in the use of eflornithine as first line treatment and the development of the short melarsoprol treatment protocol, which has undergone a full clinical trial as a preliminary step before for any recommendation as an appropriate approach for treating patients. One could also mention the new molecule DB289 which is presently undergoing field trials. This new chemical is a promising alternative for first stage treatment. Although research is still needed, it is likely that it will also be adapted for the treatment of late stage sleeping sickness cases. Trials using nifurtimox and eflornithine combination are ongoing. Drug combination is considered a promising approach as an alternative therapy to avoid resistance. Furthermore, new molecules are under consideration and novel diagnostic tests are being validated. One of these tests is a highly specific and sensitive serological assay while another is an agglutination test to assess the involvement of the nervous central system. Other diagnostic tools are under consideration and there is good hope for their further development. Thus, networking has allowed the development, validation and introduction of new techniques in restructured and reinforced national programmes, which continue to receive seeding financial support to enhance surveillance and control. Training continues to provide the essential competence to implement the new tools as they become available.
Certainly there are still countries where surveillance and control are still weak but improvements are constantly being made. It is unlikely that the disease will ever be eradicated, due to the nature of its reservoir, but it will undoubtedly be eliminated as public health problem. It is now time to look at the approaches and methodologies to sustain the results obtained. It seems timely to identify tools that can be integrated into health delivery systems to maintain surveillance. Sleeping sickness has been and occasionally still is an obstacle to rural development but it will soon be time to look at other diseases that represent stumbling blocks.
This 10th PAAT Advisory Group Coordinators’ meeting should certainly take note of the recent success which is the result of organized determination, strong collaboration and networking. Everyone here should be satisfied to have brought a building stone to the edifice.
In that context, FAO has progressed towards the improvement of meat and milk production and towards a better, more productive and sustainable agriculture, leading to rural development and food security in T&T affected areas. Together, lead agencies are moving more efficiently towards the ultimate goal of an improved economic and social status of the African population.
[Due to lack of space the following sections are presented here by the titles and speakers only, but are due to appear soon in full in the report of the PAG meeting on the main AGA webpage as well as on the PAAT website (see www.fao.org/ag/paat.html)]
7. Progress on the refinement of the concept note for Burkina Faso and Mali: information available and information needed - I. Sidibe
8. Concerted action: the role and contribution of international research institutes (CIRAD, CIRDES, ITC, ITM) in supporting T&T intervention and related research activities - S. de la Rocque, I. Sidibe, K. Agyemang, S. Geerts
9. Concerted action: the role and contribution of NARS in T&T intervention and related activities - V. Codjia, I. Tamboura, C. Mahama, E. Coulibaly, C. Ly
10. Advancing together: from Burkina Faso, Mali and Ethiopia experience, the role of PAAT in assisting African countries in defining national T&T/SARD strategies as related to proposal(s) for joint international intervention - Moderators P.Holmes, A.A. Ilemobade
11. Report on advancement of FAO-IFAH partnership for Quality Control/Quality Assurance of trypanocides - R.C. Mattioli
12. Identification of areas for additional public-private sector partnership and support - Moderator V. Codjia.
The following items of interest to the readership of TTI are summarised from Insect Pest Control Newsletter, No. 64, published by the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture and FAO/IAEA Agriculture and Biotechnology Laboratory, Seibersdorf, Austria.
Ongoing Technical Co-operation Project: Feasibility Studies for Area-wide Intervention in Mali
The suitability of an area for intervention against its tsetse infestation depends on several factors. One is the extent of the tsetse infestation, considered on a species-by-species basis. Another is the possibility of re-invasion of cleared areas by flies from outside the cleared zone; a critical issue here is the efficiency of natural barriers such as watersheds between river basins to prevent re-infestation. Lastly, it needs to be confirmed that the control method under review actually works in the particular study area. The TCP project has addressed several of these factors.
A survey of Glossina palpalis gambiensis distribution was carried out in the northern part of the Niger River Basin. After study of previous survey results, a zone of more than 9 000 km2 was surveyed. The new results indicated that most flies were taken from the vegetation of the left bank of the Niger River, and the northern limit to the present-day distribution appears to be south of that found in the earlier surveys. There was some evidence of the very fragmented nature of the tsetse population distribution in this northern zone that had been predicted from theoretical studies.
The dispersal potential of the G. palpalis gambiensis populations was assessed by means of an analysis of the gene frequencies in these populations, sampling from various river tributaries. Very little genetic heterogeneity was detected in the mitochondrial DNA and genetic diversity was low, indicating past genetic bottlenecks. As there was little genetic differentiation between tsetse populations in the various tributaries, it was concluded that the respective tsetse populations were not well isolated. Larger-scale sampling is called for to amplify these preliminary results.
The above genetic study was complemented by a release-recapture exercise. The small-scale experiment conducted using colony-reared G. p. gambiensis indicated that flies could disperse over a watershed from the Niger catchment to the Senegal Basin. Such results lead us to approach the Area-Wide Integrated Pest Management strategy with extreme caution in this instance.
Locally, tsetse (Glossina palpalis gambiensis) has been drastically suppressed using insecticide-impregnated Vavoua traps in the extended peri-urban area around Bamako. The intervention zone is to be increased, but in future it is expected that the first zone will be monitored and action taken at points where the fly is beginning to recover in numbers.
Developments affecting tsetse rearing at the Entomology Unit, Seibersdorf
A semi-automated system for rearing flies (TBU3) is being installed at Seibersdorf. The idea is to reduce further still the stress imposed on the breeding female tsetse flies, to encourage maximum productivity. The new unit also allows greater ease of management, so that one or two technicians can deal with a colony of more than a million females. It was anticipated that the new installation would be completed by January 2005.
Efforts are being made to automate the sexing of tsetse pupae, using a near infra-red spectrometer. After the delivery of the spectrometer, tests will be carried out on Glossina pallidipes pupae, to separate them automatically into males and females. If these trials are satisfactory, the technique will be extended to other species.
Some basic research into sound production in tsetse is being conducted. The pattern of sound production, the frequency spectrum of the sounds, the effects of time of day on calling are some of the areas being investigated. It is hoped that studying the sounds produced by tsetse will give information concerning factors important in successful mating, and help towards making a general index of fly fitness useful in colony quality control.
Possible improvements to the quality of the blood fed to the fly colonies are being studied. Pasteurization is a possible alternative to irradiation to reduce bacteria in the blood feed. Various anti-coagulants are being tested, as well as other additives such as dyes, and trials are under way to test the advantages of different ratios of amino acids and lipids.
The frequency and effect of re-mating in female tsetse flies has been studied in G. pallidipes and G. brevipalpis. In G. pallidipes, a low rate of re-mating (0 - 10 percent) was observed. It was felt that such levels were unlikely to have a significant effect on an SIT programme as sterilised males will be released in very high numbers compared to the flies present in the field. In G. brevipalpis, a small genetic study gave preliminary indications that where a female mated twice, the second-mating male’s sperm were used for fertilizing the eggs. More observations are needed here.
