J Vet Sci.  2012 Sep;13(3):293-298. 10.4142/jvs.2012.13.3.293.

The effect of seasonal variation on anthrax epidemiology in the upper Zambezi floodplain of western Zambia

• Munang'andu HM
• Banda F
• Siamudaala VM
• Munyeme M
• Kasanga CJ
• Hamududu B

• KMID: 1389769
• DOI: http://doi.org/10.4142/jvs.2012.13.3.293

Abstract

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.

Keyword

anthrax; epidemiology; floodplain; Zambezi

MeSH Terms

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

Figure

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  Fig. 1 Monthly distribution of livestock and human cases of anthrax from 1999 to 2007.

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