Application of a capture enzyme immunoassay in an outbreak of waterborne giardiasis in the United Kingdom.

A capture enzyme immunoassay (EIA) for the detection of Giardia lamblia antigen was used to examine 136 fecal samples collected during an outbreak of waterborne giardiasis in a city in the UK. Six cases of Giardia lamblia infection were detected that had previously not been diagnosed by microscopy. The capture EIA provides an efficient means of processing large numbers of samples for prompt and accurate assessment of an epidemic. It may also facilitate rapid tracing of epidemic sources.