Conclusions - Waterborne Pathogens: Detection Methods and Applications - page 373

detailed characterization of pathogens, to the subspecies level as well as
viability determination, and these approaches will be very useful in certain
types of monitoring. Alternatively, other methods such as biosensors can be
rapid and portable and therefore have great potential in other applications.
Optical approaches, and in particular the spectroscopic methods, offer
the promise of single organism fingerprinting to obtain detailed informa-
tion on pathogen characteristics. However, improved understanding of the
relation between pathogen species, viability, etc. and the spectra obtained is
required, as well as packaging into low-cost, easy-to-operate systems. Fur-
thermore, for all optical methods, instrument design, and miniaturization
are essential to obtain more widespread acceptance in the water quality
monitoring arena.
Electrical methods of detection have been applied to a wide range of
viruses, bacteria, and protozoa although little work has concentrated directly
on waterborne pathogens. Given the potential for detailed characterization
of single microorganisms, expanding the range of waterborne pathogens
studied is a crucial research task. Reproducibility and cost are other key
issues to be addressed.
Some biosensor technologies are now reaching toward single organ-
ism detection, which are highly promising results. However, while bio-
sensors offer speed and sensitivity there are still many challenges to be
overcome, including issues of sample processing, biofouling, and robustness.
Future research to enable species and viability discrimination would also
be extremely beneficial for the real-world application of biosensing tech-
nology to waterborne pathogen detection. Other biosensing techniques
for viruses and protozoa, perhaps particularly, electrochemical methods for
viruses and both optical and electrochemical methods for protozoa, should
also be explored.
Molecular methods have been developed for viruses, bacteria, and proto-
zoa offering speciation, and potentially, an indication of viability. An impor-
tant upcoming task is agreement on the primers and probes most suitable
for use with different waterborne pathogens, and eventually validation of
these choices in moving toward regulatory approved methods. Lowering
detection limits is also essential, especially in obtaining information from
environmental samples with low pathogen concentrations.
For all of the above techniques, nanotechnology and miniaturization
are likely to play an important role in the future development of methods.
There are many exciting opportunities in the field of nanomaterials and
nanotechnology, and more research should concentrate on applications of