Coliphage replicate much faster than E. coli and produce multiple progeny, thus enabling the Fast Phage test to give an early prediction of positive results in less than 8 hours.

The method detects as little as one plaque forming unit (pfu) in 100 mL water sample.

A conventional overnight plaque assay is part of the method and is used to confirm the early 8 hour positive prediction.

The plaque assay is similar to EPA and WHO methods for coliphage detection.

There are two types of coliphage that are of interest for detection. Somatic coliphage are DNA type viruses that are present in high numbers in both animal and human fecal material. Male specific (F+) coliphage are both DNA and RNA type virus es that are morpholigically similar to pathogenic enteric viruses and are found exclusively in warm blooded animals. Certain serotypes of F+ coliphage are used for source tracking pollution.

Different kits are available for both types of coliphage.