An analytical test device is described for the immunochromatographic determination of the presence of one or more analytes in fluid samples. The device is configured such that the sample is allowed to enter the detection zone simultaneously from many different directions, eliminating stagnation of the flow of the sample. By selection of the porous substrate, the device also allows for the separation of red blood cells from plasma, providing a rapid test for one or more analytes in a sample of whole blood. The device of the present invention may measure more than one analyte simultaneously from a single sample, either by having multiple immunochromatographic pathways fed by a single sample, or multiple analytes detected in the same pathway by way of multiple capture antibodies.