Visa is required, even if you do not leave the airport zone and do only a transit change.

If you make a transfer to the US, you need a visa category B1 / B2. To obtain a visa, you will receive a full package of documents confirming your strong financial, family and other ties with Russia (certificate from work, copies of documents on real estate, questionnaire, etc.). Interview you personally.

In Rio (Brazil) you can also fly with a transfer in Europe (via Germany, Holland or France, etc.). For transit through Europe (without going to the city), a Schengen visa is not needed.