Via SocGen comes a handy scorecard for EM vulnerability:
External position
Current account deficit currencies underperform those with a surplus in times of stress. A country with a current account deficit requires a steady inflow of foreign capital, which can dry up when sentiment toward emerging markets is depressed. Eight countries have deficits – the largest being in Turkey and South Africa – and the remainder have varying surplus levels. Since July, the dollar rallied 8% against deficit currencies (ex-Turkey) and only 2% against those with a surplus.