Infectious diseases have had a great impact on human lives and civilizations
since time immemorial. Success in controlling and eradicating these diseases,
on the other hand, has not only overcome human misery but expedited human
progress, both individually and collectively. The eradication of smallpox and
the successful control of poliomyelitis and hepatitis B can even be measured in
terms of the improvement in the world’s GDP. However, new and re-emerging
infections, including those connected to livestock such as the Nipah virus,
SARS and avian influenza, remind us to be ever vigilant and responsive to new
threats. The Newcastle disease virus (NDV) causes a highly contagious and fatal
respiratory disease in chickens and other types of birds and affects the poultry
industry worldwide. Although this virus is effectively controlled by vaccination,
it is still endemic in Malaysia and outbreaks of the disease have contributed to
major losses for the poultry industry in the country in terms of mortality and
loss in egg and meat production. By delineating the genome of this enveloped
negative single-stranded RNA virus, various genes have been sequenced,
cloned and expressed in plasmid vectors in various organisms. Knowledge of
the structural and biological characterization of NDV has provided insights into
various applications of this virus in the prevention and treatment of NDV and
other diseases as well. Although the virus replicates poorly in normal human
cells, causing mild respiratory disease and conjunctivitis, it replicates very well in
human cancer cells. This provides a potential for its use in oncology. Cancer is
an omnipresent threat to human lives, especially with, but not limited to, ageing,
a worldwide modern phenomenon. Its control and eradication remain largely
elusive, requiring considerable concerted efforts from everyone. The oncolytic
activities of the virus against human malignancies lead to tumor apoptosis and
cell death. In this respect, work is in progress to leverage NDV as a viral vector
to express and deliver foreign genes for vaccination and gene therapy purposes
for specific malignancies in humans. This of course opens up a whole new vista in research and industry, stretching imaginations and human potentials farther,
with the cherished hope of improving the lives of human beings further
