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While veterinarians have been the main driver of the One Health initiative, the medical profession does not seem to be fully aware of how veterinary science can contribute to human public health. It was postulated that transdisciplinarity could help fill knowledge gaps and that encouraging such transdisciplinarity should start with undergraduate students. Furthermore, intersectoral collaboration on zoonoses should not ignore the social sciences (e.g. assessment of indigenous knowledge and perception; participatory surveillance), which can contribute to a better understanding of the transmission of diseases and improve communities' participation in disease control activities.

Background: An integrated strategy of intervention against tsetse flies was implemented in the Upper West Region of Ghana (9.62u-11.00u N, 1.40u-2.76u W), covering an area of <18,000 km2 within the framework of the Pan-African Tsetse and Trypanosomosis Eradication Campaign. Two species were targeted: Glossina tachinoides and Glossina palpalis gambiensis. Methodology/Principal Findings: The objectives were to test the potentiality of the sequential aerosol technique (SAT) to eliminate riverine tsetse species in a challenging subsection (dense tree canopy and high tsetse densities) of the total sprayed area (6,745 km2) and the subsequent efficacy of an integrated strategy including ground spraying (<100 km2), insecticide treated targets (20,000) and insecticide treated cattle (45,000) in sustaining the results of tsetse suppression in the whole intervention area. The aerial application of low-dosage deltamethrin aerosols (0.33-0.35 g a.i/ha) was conducted along the three main rivers using five custom designed fixed-wings Turbo thrush aircraft. The impact of SAT on tsetse densities was monitored using 30 biconical traps deployed from two weeks before until two weeks after the operations. Results of the SAT monitoring indicated an overall reduction rate of 98% (from a pre-intervention mean apparent density per trap per day (ADT) of 16.7 to 0.3 at the end of the fourth and last cycle). One year after the SAT operations, a second survey using 200 biconical traps set in 20 sites during 3 weeks was conducted throughout the intervention area to measure the impact of the integrated control strategy. Both target species were still detected, albeit at very low densities (ADT of 0.27 inside sprayed blocks and 0.10 outside sprayed blocks). Conclusions/Significance: The SAT operations failed to achieve elimination in the monitored section, but the subsequent integrated strategy maintained high levels of suppression throughout the intervention area, which will contribute to i

OBJECTIVE In Southeast Asia, malaria vectors bite outside the houses before bedtime, and forest dwellers rarely use insecticide-treated nets (ITNs). Thus, we tested the protection of long-lasting insecticidal hammocks (LLIH) using Olyset (TM) technology against exophagic vectors in two forest villages of Cambodia. METHODS In each village, we conducted two entomological surveys ( middle and end of the rainy season), each lasting 10 consecutive nights. These comprised human landing collections during the whole night by people sitting outside in the hammocks. Five households were selected per village, and for each household, two fixed positions were allocated: one for the control and one for the treated hammock. RESULTS In total, 6449 mosquitoes were collected from control hammocks compared to 4481 in treated hammocks. Personal protection conferred by the hammocks was 46% (CI 95%: 35-55%) against the bites of Anopheles minimus. A significant reduction of An. dirus bites ( 46% CI 95%: 25-62%) was only observed at the end of the rainy season. An. maculatus and culicines bites were only reduced in one of the two study sites. CONCLUSION Even if this LLIH is not inducing full protection against the bites of malaria vectors, it could prove effective in protecting forest workers and villagers before sleeping time. LLIH can be an additional and valuable tool in eliminating artemisinin-resistant malaria in the region.

Background: Because of the development of resistance in trypanosomes to trypanocidal drugs, the livelihood of millions of livestock keepers in sub-Saharan Africa is threatened now more than ever. The existing compounds have become virtually useless and pharmaceutical companies are not keen on investing in the development of new trypanocides. We may have found a breakthrough in the treatment of resistant trypanosomal infections, through the combination of the trypanocide isometamidium chloride (ISM) with two affordable veterinary antibiotics. Methodology/Principal Findings: In a first experiment, groups of mice were inoculated with Trypanosoma congolense strains resistant to ISM and either left untreated or treated with (i) tetracycline, (ii) ISM or (iii) the combination of the antibiotic and the trypanocide. Survival analysis showed that there was a significant effect of treatment and resistance to treatment on the survival time. The groups treated with ISM (with or without antibiotic) survived significantly longer than the groups that were not treated with ISM (P < 0.01). The group treated with the combination trypanocide/antibiotic survived significantly longer than the group treated with ISM (P < 0.01). In a second experiment, groups of cattle were inoculated with the same resistant trypanosome strain and treated with (i) ISM, (ii) ISM associated with oxytetracycline or (iii) ISM associated with enrofloxacine. All animals treated with ISM became parasitaemic. In the groups treated with ISM-oxytetracycline and ISM-enrofloxacine, 50% of the animals were cured. Animals from the groups treated with a combination trypanocide/antibiotic presented a significantly longer prepatent period than animals treated with ISM (p < 0.001). The impact of the disease on the haematocrit was low in all ISM treated groups. Yet, it was lower in the groups treated with the combination trypanocide/antibiotic (p < 0.01). Conclusions/Significance: After optimization of the administration pr

Theileria parva is the causative agent of East Coast fever (ECF), an important cattle disease in East and Central Africa. One of the methods for control of ECF is 'infection and treatment', a procedure in which an animal is infected with the live parasite and at the same time treated with a long-acting oxytetracycline formulation, restraining the infection and allowing a protective cellular immune response to develop. Optimal immunizing doses were estimated using models of trichotomous response: dysimmunization (death or severe reaction during immunization), immunization failure (death or severe reaction during lethal challenge) and successful immunization (neither dysimmunization nor immunization failure). In this paper we present methods of interpreting immunization trials and apply these methods to previously unpublished data from two such trials: one with a mixture of three T parva stocks and one with a single T parva stock. We explain why titration trials conducted with a cocktail of antigens could predict a suboptimal immunization dose. Indeed it is possible for a combination of three individually efficient stocks to result in a mixture with which optimal immunization response might be difficult to achieve, because of averaging effects. The corresponding interpretation provides insights into why standard immunization trials for T parva have not yielded the results that might be expected of them. The results of this work may also have implications for the use of antigen cocktails in cancer, HIV and malaria vaccine trials. (c) 2007 Elsevier Inc. All rights reserved.

Immunization agairist the protozoan Theileria parva by infection and treatment has proved to be very efficient for the Control Of East Coast fever, an acute and often-fatal lymphoproliferative tick-borlic disease of cattle in Eastern, Central and Southern Africa. The immunizing dose of live T. Parva sporozites used in this method is usually determined by in vitro titration. An alternative in vivo method of quantitification of sporozoites ill whole tick-derived stabilites is proposed. The method consists of incubating serially diluted T. Parva stabilities with boville peripheral blood lymphocytes, the host cell that is infected naturally. Allowing the cultures to incubate undisturbed for the full cultivation period (10 days) reduced the variability amoung replicate titrations. fungal contaminations were avoided by centrifuging stabilates at 400 g prior to the incubation, which did not precipiate sporozoites significantly. Fungistics, Nysatin and Flucytosine did not appear to interfere with the in vitro development of 2 stabilates but their effect on fungal growth was limited. In vitro titration data were compared to in vivo infection data for 2. In vivo titration of T. parva sporozoites should allow more ethicl and efficient research on the preparation and storage of T. Parva tick-derived stabilates.