Abstract: Methods for detecting microorganisms in a sample by binding detectable particles and fluorescent labelled ligands reactive to the microorganisms. The present invention also includes the use of multiple fluorochromes for the detection of microorganisms and is adaptable for use in flow cytometry.

Abstract: Oligonucleotide molecules and methods are disclosed for the detection of viable oocysts or other cells of the protozoa species, Cyrptosporidium parvum. Preferred oligonucleotide molecules are selected from the group comprising oligonucleotides having one or more of the following sequences: (a) ACA ATT ATT, (b) CTT TTT GGT, (c) ATT TTA TAT AAA ATA TTT TGA TGA A, (d) TTT TTT TTT TTA GTA T, (e) TAT ATT TTT TAT CTG, (f) CTT TAC TTA CAT GGA TAA CCG, or comprising a part of the sequences (a) to (f) above so as to allow specific hybridization to unique 18S rRNA sequences of C. parvum.