Guy Brice Parfait Kolelas’ family members say they are trying to fly him to France for treatmentThe leading opposition candidate in Congo-Brazzaville’s presidential election is in hospital with Covid-19 while voting is under way.In a video circulating on social media, 61-year-old Guy Brice Parfait Kolelas is seen briefly removing an oxygen mask to tell his supporters that he is “fighting death”.He urges them to vote in the election.Mr Kolelas, who is diabetic, is one of six candidates running against President Denis Sassou Nguesso.Family members have said they are trying to arrange for him to be evacuated to France for treatment.Mr Kolelas missed his final campaign event on Friday after saying a day earlier that he feared he had malaria, the Associated Press news agency reports.He was admitted to a private hospital in the capital, Brazzaville, and it was later confirmed that he had Covid-19.Speaking in French from his hospital bed, Mr Kolelas said: “My dear compatriots, I am in trouble. I am fighting death. However, I ask you to stand up and vote for change. I would not have fought for nothing.”Mr Kolelas came second in the last election in 2016, obtaining only 15% of the vote compared with Mr Sassou Nguesso’s 60%.Story continuesMr Sassou Nguesso, 77, is widely seen as an authoritarian ruler who is expected to win again.The watchdog group NetBlocks reported that the internet had been shut down ahead of Sunday’s voting.The largest opposition party, the Pan-African Union for Social Democracy (UPADS), is boycotting the election, saying it fears the poll could divide the nation.Congo-Brazzaville’s Catholic Church episcopal conference has said it has “serious reservations” about the election’s transparency.President Sassou Nguesso has ruled for more than 35 yearsMr Sassou Nguesso has been in power since 1979, except for a five-year period after losing elections in 1992.After casting his ballot, he wished Mr Kolelas a swift recovery, Reuters news agency reports.Congo-Brazzavile has officially recorded more than 9,000 cases of Covid and 130 deaths.A foregone conclusionAnalysis by Will Ross, BBC World Service Africa editorIt is hard to find anyone who thinks President Sassou Nguesso could lose this election.After the last poll, two of his rivals were locked up. Some opposition parties argue the entire electoral system is run by the ruling party.Suspicions of foul play will not have been helped when the internet was cut off.Critics of the president say new leadership is needed in a country where more than half of the population is under-25. The economy, too, has been hit hard by a fall in the price of crude oil and the effects of the coronavirus pandemic.