The letter refers to the WHO decision this month to declare the year-long Ebola outbreak in eastern Congo a global health emergency. More than 1,700 people have died in the second-worst Ebola outbreak in history.
Saudi Arabia also suspended visas during West Africa's Ebola outbreak a few years ago in which more than 11,000 people died. The new decision affects anyone coming from Congo, including non-citizens. Congo's government has not responded publicly.
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