Actually, the WHO list has basically been discontinued. Rather, the ECFMG relies on IMED from FAIMER (wow, four abbreviations in one sentence). List is searchable at IMED - FAIMER International Medical Education Directory

And St. Theresa's IS listed in IMED, which makes grads eligible to apply for the USMLE through ECFMG.

However, do note that St. Kitt's & Nevis has no less than five IMED-listed schools. Pretty impressive for a nation of less than 39,000 souls.

Personally, I do not fully understand why people would want to trust their future to a school which cannot point to a single graduated student, and basically has no track record whatsoever (apart from the highly dubious records of several senior officials, apparently). But to each their own.

Do note, however, that legislation is considered in Congress which would significantly reduce the number of US Residencies (which are essentially federally funded). If that would happen, it would invariably SEVERELY hit anybody graduating from a foreign medical school, including ALL the Carib schools, and the less well established would, all other things being equal, be hardest hit.