As European leagues prepare to return from the enforced coronavirus break, screening tests are revealing cases in various championships, although, as yet, not calling into question plans to resume playing. Germany still plans to be the first of the five "big" leagues ahead of Spain, England and Italy - France has declared its season over - to kick off on May 16, behind closed doors, despite the sobering events at Dynamo Dresden. The second-tier club were ordered to self-isolate for 14 days on Saturday after testing uncovered two fresh coronavirus cases. "It's not a reason to call the entire season into question," league CEO Christian Seifert told German broadcaster ZDF. "It was always clear to me that this could happen. We're at the very beginning of the restart." Seifert warned, however, that further coronavirus cases could jeopardise plans to end the season by June 30. "It can reach a scale where it's not feasible anymore," he said. "It would depend on how much time there is left to finish the season." Matches will be played behind closed doors and with a maximum number of 300 people, including both teams, allowed at each game. In the run-up to the restart, all teams must go into a one-week quarantine training camp. The German league said on Thursday that 1,724 tests at the 36 clubs in the top two divisions conducted in two rounds yielded 10 positives in the first batch and two more in the second. Those include two players and a fitness coach at Cologne and a player and a physiotherapist at Borussia Moenchengladbach, but only the individuals concerned were placed in quarantine and the teams continued training. - Three cases in Brighton, five in Spain - In the English Premier League, which hopes to resume from June to August, a third Brighton player tested positive on Saturday and was placed in isolation, the club's chief executive Paul Barber told Sky Sports. The player was not named. One Brighton player tested positive in March and another in April and have recovered, the club said "It is a concern," Barber said. "Despite all of the measures that we've been taking over the past few weeks, where the players haven't been involved in any significant training at all, we've still suffered another player testing positive for the virus." Elsewhere, players at Chelsea and Norwich as well as Arsenal manager Mikel Arteta tested positive while players at Leicester, Everton and Bournemouth all self-isolated after showing symptoms but clubs did not confirm if they tested positive. Representatives of the Premier League and clubs are due to meet on Monday to discuss the final details of the "Project Restart", including the organisation of matches behind closed doors, on neutral ground and the extension of player contracts. In Spain, players in the top two divisions were allowed to carry out individual work at training grounds last week at the start of a programme aimed at restarting competition in the middle of June. On Sunday, La Liga said five players had tested positive. The five players, who have not been named, will be quarantined at home and tested again "in the next few days". "All of them are asymptomatic and in the final phase of the disease," said the La Liga in a statement. They will be allowed to rejoin their club's training programme only after two consecutive negative test results - Cases in Italy and Portugal - In Italy's Serie A, which resumed individual training this week, four Sampdoria players, including one who had previously recovered, and three from Fiorentina have tested positive for coronavirus, the clubs announced on Thursday. Clubs will have to wait until May 18 at the earliest to start group training, and the sports minister warned on Wednesday that it was "impossible to set a definite date" for the resumption of matches. AC Milan technical director Paolo Maldini, who is recovering, and Juventus striker Paulo Dybala, who has been given the all clear, were among the most notable early football victims. In Portugal, three players at top-flight Vitoria Guimaraes have tested positive. They "are clinically healthy, asymptomatic and in quarantine," the club said in a statement on Saturday. The government announced on April 30 that the first division was authorised to resume from the last weekend in May, behind closed doors and subject to the approval of a health protocol.