South Africa says non-citizens arriving from Ebola-affected areas of West Africa will not be allowed into the country, with borders closed to people from Guinea, Liberia and Sierra Leone.
All non-essential outgoing travel to the affected countries has been banned.
Senegal also said it was suspending flights with Ebola-affected countries, and closing the border with Guinea.
Cameroon and the Ivory Coast earlier imposed travel bans, despite World Health Organization warnings not to.
South African nationals will be allowed to re-enter the country when returning from high-risk countries, but will undergo strict screening, the health ministry said on Thursday.
Usual screening procedures are in place for those who travel between Nigeria, Kenya and Ethiopia, which have been defined as medium-risk countries.