No, no other country has sent anybody as far away as the United States. The Russians routinely sent people to their Mir space station, which had an apogee of 262 miles; this is still about 340 miles short of the beginning of the Inner Van Allen belt.

Only the Apollo Moon missions and at least one Gemini got into the Van Allen Belt zones. Gemini 11 reached an apogee of 850 miles, still the highest orbit of the Earth on record; the Van Allen belts begin around 600 miles up.

Since NASA is the only organization to put men through the Van Allen belts, and are conducting studies of them to this day, you'd probably want to visit their website, or that of the Van Allen probes: http://vanallenprobes.jhuapl.edu/ , for more specific information on them. /r/askscience would probably be a better jumping off place as well.

Just don't do the "assuming it to be true" thing over there. Your question would almost certainly be deleted.