Distribution of Rift Valley fever among cattle in Zambia.

In the present study, 1,421 cattle in 32 herds within nine districts, which are important cattle-producing centers in the nine provinces of Zambia, were tested for Rift Valley fever by the indirect immunofluorescence assay. One hundred and forty-seven cattle (10.5%) in 28 herds (88.9%) in the nine districts tested were positive for Rift Valley fever implying a country-wide distribution. In districts associated with flood plains and/or "dambos" (low lying areas of perpetual flooding), high herd and individual positive rates (100% and > 10%, respectively) were found, suggesting a significance of these features in the distribution of the disease.