Cameroon is gearing up for the Africa Cup of Nations, but there is scepticism due to Covid and security concerns. Stadiums at Afcon, which starts on Sunday, have their capacity capped at 80 per cent for the host's matches due to the coronavirus pandemic, the African Football Federation said. Other fixtures in the competition, which ends on February 6, will only be played in front of 60 percent of the ground's capacity. Strict coronavirus regulations have been put in place for the tournament, postponed from last year due to the virus. Security forces are also on high alert after armed groups sent threatening messages. Teams are scheduled to play in the coastal town of Limbe, and one of the training sites in Buea is a hotspot of unrest. The tournament received more disconcerting news on Thursday after Arsenal star Pierre-Emerick Aubameyang tested positive for Covid-19, days before Gabon's opening Africa Cup of Nations match. Aubameyang, teammate Mario Lemina and assistant coach Yala Anicet all tested positive after taking a lateral flow test and are awaiting the PCR results. "They underwent a PCR test and are isolating in their hotel," said coach Patrice Neveu. Aubameyang is at risk of missing Gabon's opening Group C match against Comoros on January 10. The tournament begins on Sunday with the match between hosts Cameroon and Burkina Faso at the Olembe Stadium in Yaounde.