To use youtube for the first airing of results as extraordinary as these is, well, unorthodox, If this is real at all, the spliced genes are to offer the babies protection against infection, with the babies in an HIV-laden experiment to further the cause - of what, exactly?
To ensure these childrens' health, you would need to administer anti-AIDS medicine at the first sign of infection, but that would defeat the purpose of any experiment. *If* He Jiankui is sincere, he may face the choice between a proper experiment and the childrens' health. An interesting case for the Chinese authorities.