我是真的不明白。跟身体接触的部分根本碰不到电机啊，相连的就是根通气塑料管子，一头接电机，一头接挤奶的杯子？除非细菌能通过空气传染，这奶怎么可能被污染到呢？话说回来，如果真能通过空气传染那跟Medela也没什么关系了。
个人认为Medela是因为商业理由或者怕承担法律责任危言耸听。一个PIS几百块，竟然还只是single use，也就是因为没有太多竞争对手。
Ok, let me give an easier example. Have you used a humidifier before? You put water in, and the humidifer will blow air out, and the air will contain water particles in it. You won't see the "water" in the air that comes out from the humidifier, but in fact, there is "water" there, and it's a large amount of water in fact, coz you filled in like a litre of water in the humidifer and they will be blown off overnite.
From my understanding of how the pump works, one side of the 电机 sucks the air in so it will extract the milk from your breast, and the other side of the 电机 blows the air out so the milk will be pushed to the cup.
Even though you don't see the "air" contains "milk" and possibily "blood" in it, it actually does contains some (similar to humidfier, you don't see the water in it, but the water is there in the air that is blown out). And those milk that passes through the 电机 is contamminated because there's a part in the 电机 that you can't replace or clean, and you don't need a lot of contaminated milk to spread the disease (like sharing needles in the clinic, you won't see a big drop of blood on the needle head, but you know it does spread the disease)
I don't really see it simply as a 商业理由. If there's a good resale market for the pump, then people will be willing to pay higher price for the pump coz they know they can get the money back when they sell it later (like cars, diamonds, real estate that have resale values) . And the manufacturer can also sell more "parts" to make profit. You know, if a person can't afford $260, then that's the end of the story, but if a used one is available for $100 the new parts are $60, then that person may buy it and the manufacturer can still make profit on that $60, and then the pump is recycled to another person who originally can't afford it but now will spend another $60 to buy the parts and so on and so on. In an economics point of view, the manufacturer will always benefit no matter you resell it or not.
