These components are packaged as CommonJS modules. One way to access CommonJS modules from ClojureScript is to combine them into a single JavaScript file that can be included in your ClojureScript assembly.
You will need to create a JavaScript entry point file that will require your various NPM dependencies and expose them to ClojureScript (e.g. setting them to window). Create a file (name it index.js) containing:
window.YouTube = require('react-youtube');
Then use a tool like Browserify to link the entry point file and all the dependencies it needs:
npm install -g browserify
browserify index.js --standalone window > bundle.js
Include bundle.jsClojureScript in your build and you can access the React component from ClojureScript withjs/YouTube