Snopes has already tackled this.

Using some very specific analyses, one could make the case that (at least within the last several years) about 643,000 Americans declared bankruptcy annually due to medical bills. But the accuracy of those analyses is open to question, the playing field has changed significantly since they were undertaken (due to the implementation of the ACA), and it’s far from an absolute that the other countries listed in the meme experience zero medical-related bankruptcies.

Also it is not necessarily true that there are zero bankruptcies due to medical costs in the other countries. None of the countries cover 100% of all possible medical costs, and some people choose to do medical procedures that are not covered at their own expense.

Snopes has already tackled this.

Using some very specific analyses, one could make the case that (at least within the last several years) about 643,000 Americans declared bankruptcy annually due to medical bills. But the accuracy of those analyses is open to question, the playing field has changed significantly since they were undertaken (due to the implementation of the ACA), and it’s far from an absolute that the other countries listed in the meme experience zero medical-related bankruptcies.

Also it is not necessarily true that there are zero bankruptcies due to medical costs in the other countries (though the US is definitely the leader). None of the countries cover 100% of all possible medical costs, and some people choose to do medical procedures that are not covered at their own expense.