[Max Jian]

My allergy improved when I returned to HK from Nevada and Wisconsin. The allergy was worse when I lived in Melborne and Brisbane. Again, the problem was in better control when I moved back to Hong Kong. The dry wheather actually could be a factor of asthma but in Hong Kong its humidity actual ease the problem. In HK, I can choose how often to turn on the dehumidifier. But in those locations with dry weather, I need humidifier but I wouldn't recommend to use this kind of applianc because itself can be a source of germs. I guess my allergy is less of the air pollution but more specific to dust mites, pollens and molds. So far I figure out what suits me best is to avoid living in the areas with green (avoid the pollens), avoid low floor and old building (must be no false ceiling and no carpet) and only go for the top top floors of newly developed high rise in the metro area with lots of windows.