Anthrax has become endemic throughout the upper Zambezi floodplain located in the Western Province of Zambia over the recent years. To date, no comprehensive study has been carried out to determine whether recurrence of anthrax outbreaks may be linked to differences in precipitation and human activities. Retrospective data for the period 1999 to 2007 showed that a total of 1,216 bovine cases of anthrax were reported. During the same period, 1,790 human anthrax cases and a corresponding case fatality rate of 4.63% (83/1,790) was documented in the upper Zambezi floodplain. Occurrence of human cases was highly correlated with cattle outbreaks (r = 0.94, p < 0.001). Differences in precipitation were significantly associated with the occurrence of anthrax outbreaks (chi2 = 4.75, p < 0.03), indicating that the likelihood of outbreaks occurring was higher during the dry months when human occupancy of the floodplain was greater compared to the flooding months when people and livestock moved out of this region. Human dependency on the floodplain was shown to significantly influence the epidemiology of anthrax in the upper Zambezi floodplain of western Zambia. Methods for mitigating anthrax outbreaks by disrupting the cycle of transmission are herein highlighted.
Animals ; Anthrax/*epidemiology/prevention & control/transmission/*veterinary ; Cattle ; Cattle Diseases/*epidemiology/prevention & control/transmission ; Climate ; Disease Outbreaks/*veterinary ; Human Activities ; Humans ; Retrospective Studies ; Seasons ; Zambia/epidemiology ; Zoonoses/epidemiology/microbiology/transmission

OBJECTIVETo study the current situation and the cause of schistosomiasis resurgence in order to provide reference for formulation of control strategy.

METHODSData in 1999 - 2003 and baseline data in some areas were collected and analyzed retrospectively.

RESULTSResurgence was seen in 6.15% (16/260) of the areas and one farm where transmission of schistosomiasis had been interrupted and 33.33% (21/64) of the areas already under control. Snails appeared to have been rebounded only in six counties (farm) while in thirty two counties that rebound was seen in both snails and disease prevalence. Tendency of increase in the total numbers of patients, acute patients and cattle with schistosomiasis, areas with snails were seen from 1999 to 2003.

CONCLUSIONSEnvironmental, ecological, societal factors such as flood, acequia, lack of expenditure and lack of incentives at work etc. contributed to the resurgence of epidemics in those areas that criteria had been reached. Surveillance and supervision on the sources of infection and snail diffusion, especially in the areas where the transmission of schistosomiasis had already been under control.

Animals ; Cattle ; China ; epidemiology ; Communicable Diseases, Emerging ; epidemiology ; prevention & control ; Disasters ; Disease Reservoirs ; Ecology ; Humans ; Prevalence ; Retrospective Studies ; Risk Factors ; Schistosomiasis japonica ; drug therapy ; epidemiology ; prevention & control ; Snails ; parasitology