Dust Mites CarpetFungus/bacteria Viruses
These little buggers above have been causing problems in carpets for quite awhile. The center one is particularly important as it causes the majority of people to get sick and not breath as well. The air quality in a home is determined by how "clean" a person's carpets are. I don't mean how many spots you have or how often you even vacuum. A carpet must be sanitized once a year at a minimum. If you have animals in the mix then you have further problems and could use sanitation twice a year
Brighten your day 
by
sanitizing!