Health authorities in the Spanish region of Catalonia say they have detected potential traces of the Omicron coronavirus variant in sewage samples from late November, reports Reuters.

If confirmed, it would mean the variant was present in Catalonia before or at the same time it was first reported in southern Africa a week ago.

Spain has detected two cases of the variant and expects to confirm another two by the end of the week, but all are in people who had visited countries where Omicron has been found.

“At the moment what we have are signs. In some areas of Catalonia there are some samples with specific mutations linked to this variant,” regional public health chief Carmen Cabezas told a news conference. She added that they could be also compatible with the Alpha variant.