Register a LLC in the US, which is not expensive at all, this should get you on the road to sending DMCA takedowns to at least the US sites hosting your content. Here on HN, search for the user named grellas, who is a lawyer and may be able to guide you in that regard.
Disclaimer: IANAL
Nice site! Like the illustrations, had fun brushing up on things from my medical school days.
Disclaimer: IANAL
Nice site! Like the illustrations, had fun brushing up on things from my medical school days.