How hygienic is it without a bag?

Certified hygienic emptying. In contrast to other bagless systems, the operating principle systematically separates coarse soiling from fine dust. It is then collected in a separate container with the help of the Gore® CleanStream® fine dust filter. Whilst being emptied, fine dust is kept under control. This innovative separation of fine dust guarantees hygienic emptying and was certified for this reason.
Gore® CleanStream® fine dust filter
The innovative principle of separating coarse soiling into a transparent dust container and fine dust into a different filter container enables especially hygienic emptying of the Blizzard. When compared to other bagless systems, the Miele Blizzard excels with significantly less fine dust escaping during emptying.
The dust container can be easily removed from the appliance by pulling the handle in an upward motion. With one click on the “empty” button, the container opens and all the dust drops into the bin.
Unique sensors monitor the Gore® CleanStream® fine dust filter. The ComfortClean function cleans the fine dust filter automatically as needed. After several seconds, the Blizzard CX1 is ready for use again and keeps vacuuming powerfully.
Exhaust filter 
The exhaust filter in the Miele Blizzard CX1 saves time and lifecycle costs. It is absolutely maintenance-free and of such high quality that it lasts for the entire life of the appliance. It never needs to be changed or cleaned.
IBR certification
The American institute is one of the leading global providers of modern tests to review filtration performance. The especially hygienic emptying of the Miele Blizzard CX1, which is based on the innovative operating principle of dust separation, was certified by the IBR.
Hygiene lifetime filter 
The Hygiene lifetime filter features very high dust retention capacity and collects 99.98% of all fine particles*. This is the type of hygienic cleanliness that you want for your home. 
HEPA* AirClean lifetime filter
Thanks to the HEPA* HEPA 13 lifetime filter, even the smallest particles such as fine dust and allergens are retained up to 99.999%* by the system. This excellent filtration performance was confirmed by the medical organization, “Allergy UK”, and certified as suitable for those with allergies. The Miele Blizzard CX1 has been given the quality “seal of approval” for its powerful overall dust retention capacity.
According to EN 60312-1According to EN 1822/2011Features vary depending on model. Images for illustration purposes only.