Abstract:
Since 1980 plague has been a human threat in the Western Usambara Mountains in Tanzania.
However, the spatial-temporal pattern of plague occurrence remains poorly understood. The main
objective of this study was to gain understanding of human activity patterns in relation to spatial
distribution of fleas in Lushoto District. Data were collected in three landscapes differing in plague
incidence. Field survey coupled with Geographic Information System (GIS) and physical sample collections
were used to collect data in wet (April to June 2012) and dry (August to October 2012) seasons. Data
analysis was done using GIS, one-way ANOVA and nonparametric statistical tools. The degree of spatial co-
occurrence of potential disease vectors (fleas) and humans in Lushoto focus differs significantly (p ≤ 0.05)
among the selected landscapes, and in both seasons. This trend gives a coarse indication of the possible
association of the plague outbreaks and the human frequencies of contacting environments with fleas. The
study suggests that plague surveillance and control programmes at landscape scale should consider the
existence of plague vector contagion risk gradient from high to low incidence landscapes due to human
presence and intensity of activities.
