Microorganisms、too embarrassed to ask others about！（Part 12）

5.1 What Microorganisms Like/Dislike
In principle, every kind of microorganisms from bacteria, fungi to viruses are the subjects for microbiological control in the manufacturing process of drug products and medical devices. The reasons why bacteria and fungi are the major subject in general microbiological control are as follows:

However, there are some exceptions. For instance, for blood products, viruses must be controlled due to the risk of contamination. Also, prions must be controlled for such products as we have had some Creutzfeldt-Jakob disease cases caused by dried human endocranium in the past.

The basic principle in microbiological control is to eliminate conditions favorable to microorganisms to the realistic extent and to introduce conditions unfavorable to them. These conditions would be as follows when we control general bacteria and fungi in quality control and manufacturing control for drug products and medical devices as I mentioned earlier:

Table 4. Conditions Favorable/Unfavorable to Microorganisms

'What I laid out in the table above are just general conditions but still they should be helpful when you plan a microbiological control for drug products, medical devices, or food products. A more concrete example of microbiological control based on Table 4 is as follows:

Table 5. Keys to Microbiological Control

Microbiological control should be done for everything such as manufacturing areas, raw/labeling and packaging materials, manufacturing site (space, the surface of the facilities, walls, floors), and operators. Needless to say, the control method will differ depending on the place, material, and human. We need to employ the method suitable to each requirement and situation based on our understanding of these characteristics.

Key points for control and examples are shown below: