28 Days Later Official Teaser Trailer

This is the teaser trailer for 28 days later, its a film that has a similar genre to the one thats first in my thoughts for my own trailer. Im thinking into a horror film as they are the ones  i watch the most of and enjoy.
Also when looking into what makes this teaser trailer effective it is a number for different things, at more than half the time its very dark coloured. There is also a lot of emphasis and different words in comparison to others.
for example the word 'infection' and 'exposure' all paint the same picture in a horror film trailer. It already makes the audience on edge and the emphasis on certain word adds great effecting in cutting from scene to scene.
Also there are many idea that i have for my trailer that are in this one. I think parts showing a deserted London with one confused person wandering helplessly adds a lot of mystery and suspense.
There are also aspects of a teaser trailer that are different to a normal one such as, they are generally shorter, don't give away much of the plot which adds to the mysterious nature of films like horror and they are normally showed before the actual trailer in order to gain publicity