Two men, originally from the Democratic Republic of the Congo and Uganda, displaying symptomssimilar to those of ebola, are being treated in isolation in Brazil, local authorities said.

The 37-year-old Congolese man “presents symptoms such as fever, which makes him a suspected case” of ebola, authorities in the state of São Paulo said, without specifying when the man arrived in Brazil. The patient “is in isolation” for precautionary reasons at a special hospital specializing in communicable diseases. Laboratory tests have not yet confirmed whether he has the virus, but analyses are continuing.

In Rio de Janeiro, the state’s local health secretariat also announced that a Ugandan man who arrived in Brazil on May 22 and is showing symptoms such as “coughing, chills and diarrhea” has been quarantined. The city’s municipality told Agence France-Presse that this man is suffering from malaria, but his case is “still being examined.”

Authorities assure, however, that the risk of the Ebola epidemic spreading to Brazil and South America remains very low.

DR Congo, one of the world’s poorest countries, has been hit by a new outbreak of Ebola since May 15 and the World Health Organization has declared a global health alert. The virus, which causes haemorrhagic fever with an extremely high mortality rate, has been detected in three provinces of DR Congo as well as in neighbouring Uganda.

According to a statement today by the African Union Health Service (Africa CDC), the two countries together have recorded 263 confirmed cases and 43 confirmed deaths, while more than 1,100 suspected cases are still under investigation. In DR Congo, 246 deaths have been recorded, but laboratory tests have not yet confirmed that all victims were infected with the virus.