BackgroundThe incidence of tick-borne diseases is increasing in Europe. Sub national information on tick distribution, ecology and vector status is often lacking. However, precise location of infection risk can lead to better targeted prevention measures, surveillance and control.MethodsIn this context, the current paper compiled geolocated tick occurrences in Belgium, a country where tick-borne disease has received little attention, in order to highlight the potential value of spatial approaches and draw some recommendations for future research priorities.ResultsMapping of 89,289 ticks over 654 sites revealed that ticks such as Ixodes ricinus and Ixodes hexagonus are largely present while Dermacentor reticulatus has a patchy distribution. Suspected hot spots of tick diversity might favor pathogen exchanges and suspected hot spots of I. ricinus abundance might increase human-vector contact locally. This underlines the necessity to map pathogens and ticks in detail. While I. ricinus is the main vector, I. hexagonus is a vector and reservoir of Borrelia burgdorferi s.l., which is active the whole year and is also found in urban settings. This and other nidiculous species bite humans less frequently, but seem to harbour pathogens. Their role in maintaining a pathogenic cycle within the wildlife merits investigation as they might facilitate transmission to humans if co-occurring with I. ricinus. Many micro-organisms are found abroad in tick species present in Belgium. Most have not been recorded locally but have not been searched for. Some are transmitted directly at the time of the bite, suggesting promotion of tick avoidance additionally to tick removal.ConclusionThis countrywide approach to tick-borne diseases has helped delineate recommendations for future research priorities necessary to design public health policies aimed at spatially integrating the major components of the ecological cycle of tick-borne diseases. A systematic survey of tick species and associated pathogens is called for in Europe, as well as better characterisation of species interaction in the ecology of tick-borne diseases, those being all tick species, pathogens, hosts and other species which might play a role in tick-borne diseases complex ecosystems.

The impact of~owers on the population growth of Frankliniella occidentalis was characterized on wax~ower plants\ Impatiens walleriana[ In the presence of~owers\ the populations grew exponentially while in their absence\ the thrips populations only maintained themselves and showed no growth The di}erence in number and in size of thrips reared in both conditions suggested that the~owers were essential for the success of thrips development[ In the presence of~owers\ the distribution of females between the leaves and the~owers varied strongly according to the availability of owers[ By contrast\ the proportion of _rst larvae in the~owers increased up to the last day of the experiment[

A life and fecundity table has been constructed for Brevipalpus phoenicis, a serious pest of plantation crops, and various demographic parameters have been calculated. Although this mite has been found to possess a low growth rate (rm = 0.127), it possesses high rates of survival even in its senescence. Under constant experimental conditions the net reproduction rate is 33.2 eggs/mite, the generation time is 27.6 days and the population doubles once in 5.5 days. The stable age profile of the population is distributed as 74.9%, 19.24% and 6.07% of eggs, immatures and adults, respectively. Another aspect considered in this paper is the evolution of the population in function of an effective initial population of 10 individuals. This mite takes a longer time to reach constant growth rate and stable age distribution (156 days), however, the population growth is astronomical. The damage caused by them passes beyond the economic injury level within 34 days by an effective initial population of 10 mites in a tea bush having 100 leaves. This suggests an earlier intervention to check the population. The demographic analysis reveals that the following five aspects of its life history, namely high survival and fertility rates, reproductive intensity in the prime youth, lack of diapause, parthenogenetic mode of reproduction and euryphagy on perennial crops, are of major importance. Reasons for the importance of these characteristics are also discussed.

In less than 3 years (1986–1988) Frankliniella occidentalis, imported from USA, had spread throughout Europe. It is a polyphagous Thysanoptera which causes important yield loss in greenhouses, in both vegetable and ornamental crops. However, insufficient data are available on its basic biology. The purpose of this work was thus to establish its life table. A cohort of 95 individuals were observed daily during their whole lifetime. The development time is short, 14.2 days, and no significant difference has been observed between males and females. The mean fecundity is high, as 43.17 larvae were produced by a single female. The intrinsic rate of natural increase is 0.140, meaning that the theoretical population may double in 4.94 days.