Hong Kong is now testing an anti-bacterial silver-titanium dioxide nanoparticle coating on surfaces in its subway cars, says ABC News. Expect to see the same in London's tube in the near future.

With news of powerful flu strains like the avian flu and hand-transmissible diseases such as colds, public transportation operators in Asia and Europe have considered using a new disinfectant in their undergrounds. Many surfaces that people touch every day in the tube, as the London subway system is called, also carry thousands of bacteria and germs, according to experts.

"Public transportation is a very common way, we know, of how diseases ... spread," says Ben Mascall, spokesman with MTR Corp., which operates the railway in Hong Kong and has bid for two new rail franchises in the United Kingdom.

"Some viruses can stay on a surface for 24 hours," says Dr. John Trainer, at the University of Rochester in New York.

Hong Kong is among the first cities to test one of the latest anti-flu products, nano silver-titianium dioxide coating, or NSTDC. It is applied to all surfaces inside a subway car. The preliminary tests conducted in Hong Kong show that the disinfectant reduces the amount of bacteria by 60 percent, says Mascall.

Ironically, titanium dioxide nanoparticles are also found in sunscreens, which the ETC Group wants banned pending further studies of their potential toxicity.