Classical pathogen detection and identifi cation is based
on culture methodology and microscopy. The culture
method is still a core technology in clinical laboratories
because the method can also provide important information
about the viability of the pathogen and its susceptibility to
antibiotics.3
However, the slow multiplication and diffi culty
of selective cultivation of many important pathogens often
limits the culture-based diagnosis.4
The direct observation
of microbes or parasites by microscopy is frequently
employed as a rapid and simple diagnostic method. The
robustness and cost-effi ciency of microscopic tests make
them acceptable to use even in resource-limited laboratories
in developing countries. However, the poor sensitivity
of smear tests often causes fatal delays in treatment and the
methodology is heavily dependent upon the skill of the
microscopist.5
Viral infection has also been diagnosed by
selective cultivation, followed by electron-microscopy
observation. A major drawback is the delay of treatment in
patients at infi rmaries in both developed and developing
countries.6,7 Accordingly, the establishment of more rapid,
sensitive, and accurate diagnostic methods has long been
desired.