Let’s say, for instance, someone with lung cancer coughs, and a few cancer cells are present in the aerosol, and is breathed in. Or, if someone has a cut, and lives with a family member who has cancer, and cancer cells end up in the cut.
Cancer cells are a bit like HIV in that they evade the immune system by releasing some chemical to trick it. Hence why in an infamous unethical experiment after the war, people injected with another person’s cancer developed cancer. So even if it is another person’s cancer cells, the cancer will metastasize in the body.
This would make cancer the most overlooked infectious pandemic in all of human history.
I know that the bar is pretty low for a shower thought, but this is irresponsibly misinformed. There is only one known form of contagious cancer, and it only affects a single species of fish in one lake.
Confidently stating that cancer is contagious between humans, in my books, is spreading medical misinformation.
This is the person who was banging on and on about chavs and canal deaths so just ignore
I would somewhat consider HPV to be a contagious carcinogen at least.
Look into the Southam experiments. It was unethical even for its time, but people were injected with cancer cells from another person without their consent and subsequently developed cancer.
Chester Southam injected live cancer cells into people who already had cancer to see if their immune systems would respond a certain way. His experiments do not in any way prove that cancer can be spread between people. His subjects had cancer before he injected them.
What Southam is mostly known for is being an immoral quack who experimented on people without their consent. He was convicted of multiple crimes related to the cruel human experiments you seem to admire for some reason.