Abstract: The assessment of surface waters in Enugu metropolis
for fecal coliform bacteria was undertaken. Enugu urban was divided
into three areas (A1, A2 and A3), and fecal coliform bacteria
analysed in the surface waters found in these areas for four years
(2005-2008). The plate count method was used for the analyses. Data
generated were subjected to statistical tests involving; Normality test,
Homogeneity of variance test, correlation test, and tolerance limit
test. The influence of seasonality and pollution trends were
investigated using time series plots. Results from the tolerance limit
test at 95% coverage with 95% confidence, and with respect to EU
maximum permissible concentration show that the three areas suffer
from fecal coliform pollution. To this end, remediation procedure
involving the use of saw-dust extracts from three woods namely;
Chlorophora-Excelsa (C-Excelsa),Khayan-Senegalensis,(CSenegalensis)
and Erythrophylum-Ivorensis (E-Ivorensis) in
controlling the coliforms was studied. Results show that mixture of
the acetone extracts of the woods show the most effective
antibacterial inhibitory activities (26.00mm zone of inhibition)
against E-coli. Methanol extract mixture of the three woods gave best
inhibitory activity (26.00mm zone of inhibition) against S-areus, and
25.00mm zones of inhibition against E-Aerogenes. The aqueous
extracts mixture gave acceptable zones of inhibitions against the
three bacteria organisms.
Abstract: Mathematical models can be used to describe the
transmission of disease. Dengue disease is the most significant
mosquito-borne viral disease of human. It now a leading cause of
childhood deaths and hospitalizations in many countries. Variations
in environmental conditions, especially seasonal climatic parameters,
effect to the transmission of dengue viruses the dengue viruses and
their principal mosquito vector, Aedes aegypti. A transmission model
for dengue disease is discussed in this paper. We assume that the
human and vector populations are constant. We showed that the local
stability is completely determined by the threshold parameter, 0 B . If
0 B is less than one, the disease free equilibrium state is stable. If
0 B is more than one, a unique endemic equilibrium state exists and
is stable. The numerical results are shown for the different values of
the transmission probability from vector to human populations.