The epidemiology of rabies in Zimbabwe. 2. Rabies in jackals (Canis adustus and Canis mesomelas).

The epidemiology of rabies in Canis adustus (the side-striped jackal) and Canis mesomelas (the black-backed jackal) in Zimbabwe is described using data collected from 1950-1996. Cases in the two species made up 25.2% of all confirmed cases, second only to domestic dogs. Since the species of jackal cases was not recorded on rabies submission forms, the country was divided into areas according to species dominance and jackal cases were assigned to either C. adustus or C. mesomelas dominant zones or a sympatric zone where the relative status of the species is not known. Jackal rabies in both species is maintained in the commercial farming sector. Jackal rabies in the C. adustus zone occurs as dense epidemics, which begin at a single focus and spread centrifugally. The foci were initiated by rabid dogs, but once initiated the epidemic is maintained by C. adustus independently of other species. The extent of outbreaks in the C. adustus zone was limited by geographical (landuse type and jackal species interface) boundaries. Jackal rabies in C. adustus zones showed two seasonal peaks with the main peak occurring during late summer and the second peak during winter. In the C. mesomelas zone jackal rabies was more sparse but it occurred during most years. C. mesomelas is also able to maintain rabies independently of other species, although the epidemiology of the disease in this species is unclear. Transmission of rabies cycles between the two jackal species zones does not appear to occur as epidemics terminate when crossing the C. adustus and C. mesomelas interface boundaries.     

Effect of a pilot community intervention on fruit and vegetable intakes: use of FACET (Five-a-day Community Evaluation Tool)

BACKGROUND: In 2001 the UK Department of Health funded pilot community-based interventions to improve fruit and vegetable intakes in five economically deprived areas of England. The effectiveness of the programme and the use of a brief tool for evaluating community interventions are reported here. METHODS: Data on intakes of and beliefs about fruit and vegetables were collected by a short postal questionnaire (FACET--Five-a-day Community Evaluation Tool) simultaneously from 810 individuals living in the pilot communities and 270 individuals who were participating in an unrelated observational study (controls). Data were collected before and after a 12-month intervention period. Quantitative dietary data derived from 7-day food diaries available for control subjects were used to assess the ability of the FACET questionnaire to estimate fruit and vegetable intakes. RESULTS: Compared with controls, the intervention group significantly increased their knowledge of the 5-a-day optimum (P<0.01) and reported increased access to fruits and vegetables (P<0.001). Overall, the intervention had no demonstrable effect on total fruit and vegetable intakes as measured by FACET. However, smoking habit strongly predicted change in fruit and vegetable intakes (P<0.01) in the intervention group. Opposite trends were observed in the two groups, with 'smokers' and 'non-smokers' in the intervention and control groups respectively reducing their fruit and vegetable intakes. The FACET questionnaire agreed with food diary estimates of fruit and vegetable intakes in 56% of cases. CONCLUSIONS: Community-based interventions can produce important changes in knowledge of and access to fruit and vegetables. However, in this study change in fruit and vegetable intakes was strongly influenced by smoking habit. This bias needs to be considered in planning future intervention and evaluation programmes. The FACET questionnaire provides acceptable estimates of fruit and vegetable intakes which may be used for grading intake in large community-based projects.     

Response of agronomic and forest species to elevated atmospheric carbon dioxide

The effects of atmospheric carbon dioxide on corn, soybeans, loblolly pine, and sweetgum were studied in the field during a growing season. The plants were exposed to a range of concentrations of carbon dioxide day and night in open-topped, flow-through chambers. At a mean daytime carbon dioxide concentration of 910 parts per million, increases in total biomass ranged from 157 to 186 percent of the control values. Seed yield and wood volume increased and there were changes in plant anatomy and form. Net photosynthesis increased with increasing carbon dioxide concentration in soybeans and sweetgum, but was unaffected in corn. Water use efficiency also increased in corn, soybeans, and sweetgum.